Scientific article
| 
09 Nov 2026
Scientific article |
| 09 Nov 2026
| 09 Nov 2026
Polar ocean–cryosphere dynamics across past, present, and future climate states: AWI research highlights 2021–2025
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Environmental Physics, University of Bremen, Bremen, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Almut Brunner
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Gesine Mollenhauer
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Christian Haas
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Environmental Physics, University of Bremen, Bremen, Germany
Thomas Laepple
MARUM – Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Research Unit Potsdam, Potsdam, Germany
Torsten Kanzow
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Environmental Physics, University of Bremen, Bremen, Germany
Ilka Weikusat
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, Eberhard Karls University of Tübingen, Tübingen, Germany
Monica Ionita
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Olaf Eisen
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Florian Adolphi
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Vera S. N. Schlindwein
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Angelika Humbert
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Karsten Gohl
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Department of Geosciences, University of Bremen, Bremen, Germany
Juliane Müller
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Klaus Grosfeld
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Johann P. Klages
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Frank Lamy
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Gregor Knorr
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Walter Geibert
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Maria Hoerhold
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Ingo Sasgen
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Daniela Jansen
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Rebecca McPherson
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Junjie Wu
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Xinyue Li
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Thomas Krumpen
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Hanna Knahl
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Helge Goessling
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Renate Treffeisen
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Peter Koehler
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Thomas Jung
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Handelshafen 12, 27570 Bremerhaven, Germany
Environmental Physics, University of Bremen, Bremen, Germany
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We developed a new atmosphere–ocean coupled climate model, AWI-CM3. Our model is significantly more computationally efficient than its predecessors AWI-CM1 and AWI-CM2. We show that the model, although cheaper to run, provides results of similar quality when modeling the historic period from 1850 to 2014. We identify the remaining weaknesses to outline future work. Finally we preview an improved simulation where the reduction in computational cost has to be invested in higher model resolution.
Xiaoxu Shi, Martin Werner, Carolin Krug, Chris M. Brierley, Anni Zhao, Endurance Igbinosa, Pascale Braconnot, Esther Brady, Jian Cao, Roberta D'Agostino, Johann Jungclaus, Xingxing Liu, Bette Otto-Bliesner, Dmitry Sidorenko, Robert Tomas, Evgeny M. Volodin, Hu Yang, Qiong Zhang, Weipeng Zheng, and Gerrit Lohmann
Clim. Past, 18, 1047–1070, https://doi.org/10.5194/cp-18-1047-2022, https://doi.org/10.5194/cp-18-1047-2022, 2022
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Since the orbital parameters of the past are different from today, applying the modern calendar to the past climate can lead to an artificial bias in seasonal cycles. With the use of multiple model outputs, we found that such a bias is non-ignorable and should be corrected to ensure an accurate comparison between modeled results and observational records, as well as between simulated past and modern climates, especially for the Last Interglacial.
Ryan A. Green, Laurie Menviel, Katrin J. Meissner, Xavier Crosta, Deepak Chandan, Gerrit Lohmann, W. Richard Peltier, Xiaoxu Shi, and Jiang Zhu
Clim. Past, 18, 845–862, https://doi.org/10.5194/cp-18-845-2022, https://doi.org/10.5194/cp-18-845-2022, 2022
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Climate models are used to predict future climate changes and as such, it is important to assess their performance in simulating past climate changes. We analyze seasonal sea-ice cover over the Southern Ocean simulated from numerical PMIP3, PMIP4 and LOVECLIM simulations during the Last Glacial Maximum (LGM). Comparing these simulations to proxy data, we provide improved estimates of LGM seasonal sea-ice cover. Our estimate of summer sea-ice extent is 20 %–30 % larger than previous estimates.
Sebastian Hinck, Evan J. Gowan, Xu Zhang, and Gerrit Lohmann
The Cryosphere, 16, 941–965, https://doi.org/10.5194/tc-16-941-2022, https://doi.org/10.5194/tc-16-941-2022, 2022
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Proglacial lakes were pervasive along the retreating continental ice margins after the Last Glacial Maximum. Similarly to the marine ice boundary, interactions at the ice-lake interface impact ice sheet dynamics and mass balance. Previous numerical ice sheet modeling studies did not include a dynamical lake boundary. We describe the implementation of an adaptive lake boundary condition in PISM and apply the model to the glacial retreat of the Laurentide Ice Sheet.
Justus Contzen, Thorsten Dickhaus, and Gerrit Lohmann
Geosci. Model Dev., 15, 1803–1820, https://doi.org/10.5194/gmd-15-1803-2022, https://doi.org/10.5194/gmd-15-1803-2022, 2022
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Climate models are of paramount importance to predict future climate changes. Since many severe consequences of climate change are due to extreme events, the accurate behaviour of models in terms of extremes needs to be validated thoroughly. We present a method for model validation in terms of climate extremes and an algorithm to detect regions in which extremes tend to occur at the same time. These methods are applied to data from different climate models and to observational data.
Daniel Balting, Simon Michel, Viorica Nagavciuc, Gerhard Helle, Mandy Freund, Gerhard H. Schleser, David Steger, Gerrit Lohmann, and Monica Ionita
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-47, https://doi.org/10.5194/essd-2022-47, 2022
Preprint withdrawn
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Vapor pressure deficit is a key component of vegetation dynamics, soil science, meteorology, and soil science. In this study, we reconstruct the variability of the vapor pressure deficit in the past and examine the changes in future scenarios using climate models. In this way, past, present and future changes of the vapor pressure deficit can be detected locally, regionally, and continentally with higher statistical significance.
Stephan Krätschmer, Michèlle van der Does, Frank Lamy, Gerrit Lohmann, Christoph Völker, and Martin Werner
Clim. Past, 18, 67–87, https://doi.org/10.5194/cp-18-67-2022, https://doi.org/10.5194/cp-18-67-2022, 2022
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We use an atmospheric model coupled to an aerosol model to investigate the global mineral dust cycle with a focus on the Southern Hemisphere for warmer and colder climate states and compare our results to observational data. Our findings suggest that Australia is the predominant source of dust deposited over Antarctica during the last glacial maximum. In addition, we find that the southward transport of dust from all sources to Antarctica happens at lower altitudes in colder climates.
Martin Wegmann, Yvan Orsolini, Antje Weisheimer, Bart van den Hurk, and Gerrit Lohmann
Weather Clim. Dynam., 2, 1245–1261, https://doi.org/10.5194/wcd-2-1245-2021, https://doi.org/10.5194/wcd-2-1245-2021, 2021
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Northern Hemisphere winter weather is influenced by the strength of westerly winds 30 km above the surface, the so-called polar vortex. Eurasian autumn snow cover is thought to modulate the polar vortex. So far, however, the modeled influence of snow on the polar vortex did not fit the observed influence. By analyzing a model experiment for the time span of 110 years, we could show that the causality of this impact is indeed sound and snow cover can weaken the polar vortex.
Kim H. Stadelmaier, Patrick Ludwig, Pascal Bertran, Pierre Antoine, Xiaoxu Shi, Gerrit Lohmann, and Joaquim G. Pinto
Clim. Past, 17, 2559–2576, https://doi.org/10.5194/cp-17-2559-2021, https://doi.org/10.5194/cp-17-2559-2021, 2021
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We use regional climate simulations for the Last Glacial Maximum to reconstruct permafrost and to identify areas of thermal contraction cracking of the ground in western Europe. We find ground cracking, a precondition for the development of permafrost proxies, south of the probable permafrost border, implying that permafrost was not the limiting factor for proxy development. A good agreement with permafrost and climate proxy data is achieved when easterly winds are modelled more frequently.
Zixuan Han, Qiong Zhang, Qiang Li, Ran Feng, Alan M. Haywood, Julia C. Tindall, Stephen J. Hunter, Bette L. Otto-Bliesner, Esther C. Brady, Nan Rosenbloom, Zhongshi Zhang, Xiangyu Li, Chuncheng Guo, Kerim H. Nisancioglu, Christian Stepanek, Gerrit Lohmann, Linda E. Sohl, Mark A. Chandler, Ning Tan, Gilles Ramstein, Michiel L. J. Baatsen, Anna S. von der Heydt, Deepak Chandan, W. Richard Peltier, Charles J. R. Williams, Daniel J. Lunt, Jianbo Cheng, Qin Wen, and Natalie J. Burls
Clim. Past, 17, 2537–2558, https://doi.org/10.5194/cp-17-2537-2021, https://doi.org/10.5194/cp-17-2537-2021, 2021
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Understanding the potential processes responsible for large-scale hydrological cycle changes in a warmer climate is of great importance. Our study implies that an imbalance in interhemispheric atmospheric energy during the mid-Pliocene could have led to changes in the dynamic effect, offsetting the thermodynamic effect and, hence, altering mid-Pliocene hydroclimate cycling. Moreover, a robust westward shift in the Pacific Walker circulation can moisten the northern Indian Ocean.
Arthur M. Oldeman, Michiel L. J. Baatsen, Anna S. von der Heydt, Henk A. Dijkstra, Julia C. Tindall, Ayako Abe-Ouchi, Alice R. Booth, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Mark A. Chandler, Camille Contoux, Ran Feng, Chuncheng Guo, Alan M. Haywood, Stephen J. Hunter, Youichi Kamae, Qiang Li, Xiangyu Li, Gerrit Lohmann, Daniel J. Lunt, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Gabriel M. Pontes, Gilles Ramstein, Linda E. Sohl, Christian Stepanek, Ning Tan, Qiong Zhang, Zhongshi Zhang, Ilana Wainer, and Charles J. R. Williams
Clim. Past, 17, 2427–2450, https://doi.org/10.5194/cp-17-2427-2021, https://doi.org/10.5194/cp-17-2427-2021, 2021
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In this work, we have studied the behaviour of El Niño events in the mid-Pliocene, a period of around 3 million years ago, using a collection of 17 climate models. It is an interesting period to study, as it saw similar atmospheric carbon dioxide levels to the present day. We find that the El Niño events were less strong in the mid-Pliocene simulations, when compared to pre-industrial climate. Our results could help to interpret El Niño behaviour in future climate projections.
Ying Ye, Peter Köhler, Martin Butzin, and Christoph Völker
EGUsphere, https://doi.org/10.5194/egusphere-2026-6527, https://doi.org/10.5194/egusphere-2026-6527, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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During the last ice age, iron-rich dust may have caused algae in the Southern Ocean to leave silicon unused, which could have fed silica-building algae in the tropics and lowered atmospheric carbon dioxide. Using an Earth system model, we find that this silicon was trapped below the surface during the glacial period. It reached tropical surface waters only after the Atlantic overturning circulation recovered from meltwater input, followed later by slower release of silicon from the deep ocean.
Lars Ackermann, Gregor Knorr, Uta Krebs-Kanzow, Lu Niu, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-6177, https://doi.org/10.5194/egusphere-2026-6177, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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Ice sheets start to grow when northern summers become cooler and less snow melts. We simulated the start of the last ice age over North America with a climate model coupled to an ice sheet model. At first, the ice sheet grows wherever summers were cold enough so that snow does not melt. Once, the ice sheet is large, it grows even into warmer regions, supported by ice flowing from its interior to its edge. Our results show that the drivers of ice growth change as the ice sheet itself grows.
Hang Wang, Hu Yang, Xiaoxu Shi, Jiping Liu, Gerrit Lohmann, Jiawang Wu, Jun Tian, Francisco W. Cruz, Jianbo Cheng, and Dake Chen
EGUsphere, https://doi.org/10.5194/egusphere-2026-5495, https://doi.org/10.5194/egusphere-2026-5495, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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Geological records of past Saharan climate are often incomplete and difficult to date, while long climate simulations require extensive computing. We therefore developed an efficient empirical model from 30 climate simulations and records of Earth's orbit, carbon dioxide and sea level. It provides a practical way to study long-term Saharan climate change and can guide future simulations, field sampling and the dating of geological and archaeological records.
Ailsa Chung, Yéva Jeaumot, Frédéric Parrenin, Daniel Steinhage, and Olaf Eisen
EGUsphere, https://doi.org/10.5194/egusphere-2026-4351, https://doi.org/10.5194/egusphere-2026-4351, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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We use a 2.5D ice flow model constrained by radar data to estimate the age of ice, basal conditions and particle paths along a flow line from Dome Fuji (DF) to the EPICA Dronning Maud Land ice core site (EDML), Antarctica. Modelled basal melt rates are highest in bedrock dips and stagnant ice occurs on or slightly downstream of bedrock highs. At EDML, particle paths show that the deepest ice may originate 130 km upstream. We also identify a potential old-ice area (>1 Ma), ~200 km from DF.
Mara Neudert, Daria Paul, Sacha van der Vleuten, Stefanie Arndt, and Christian Haas
EGUsphere, https://doi.org/10.5194/egusphere-2026-5496, https://doi.org/10.5194/egusphere-2026-5496, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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Icebergs can strongly change how snow and ice develop on Antarctic coastal sea ice, but their effects are poorly understood. We combined drone mapping with measurements of snow and ice thickness and ice cores to examine these changes. We found that thick snow on the windward side of icebergs promotes flooding and freezes into solid snow-ice, greatly increasing ice thickness while reducing ice growth from below. Snow-free areas in the lee, in contrast, had thicker ice grown from below.
Yéva Jeaumot, Frédéric Parrenin, Ailsa Chung, Olaf Eisen, Daniel Steinhage, Robert Mulvaney, Marie G. P. Cavitte, David A. Lilien, and Emilie Capron
EGUsphere, https://doi.org/10.5194/egusphere-2026-4174, https://doi.org/10.5194/egusphere-2026-4174, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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To choose good drilling sites and interpret ice cores correctly, scientists need reliable estimates of ice age at each depth. We developed a new way to model how ice behaves at the base of ice sheets, where it can melt or stop moving entirely, using radar data from Antarctica. Our estimates matched real measurements at a well-studied site, revealed a layer of stagnant ice at another, and predicted that a newly proposed drilling site could yield ice over two million years old.
Torsten Kanzow, Rebecca A. McPherson, Claudia Wekerle, Wilken-Jon von Appen, Oliver Huhn, Donald A. Slater, and Andreas Münchow
EGUsphere, https://doi.org/10.5194/egusphere-2026-5184, https://doi.org/10.5194/egusphere-2026-5184, 2026
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Atlantic Water (AW) delivers heat to glaciers in Greenland, thereby causing melt. We reveal a cooling of the AW entering the world's largest fjord system, Kangertittivaq (East Greenland), after 2018. The cooling is present on the entire Northeast Greenland shelf, driven by cooling in the Nordic Seas. In the fjord, summertime glacier meltwater drives the flow of AW towards the prominent Daugaard Jensen Glacier. The cooling is as strong as the warming of AW at the fjord over the past half century.
Nikola Jovanovic, Timm Schultz, Angelika Humbert, Thomas Kleiner, and Samuel J. Cook
EGUsphere, https://doi.org/10.5194/egusphere-2026-4224, https://doi.org/10.5194/egusphere-2026-4224, 2026
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The Greenland Ice Sheet (GrIS) has significantly melted in the last decades. However, melt formed on the surface can be stored in firn, a spongy layer between snow and ice. We use a model to simulate the change of the firn in a warming climate in regions of the GrIS. In southwest, thick ice layers (ice slabs) form. They limit the amount of water firn can store and their area increases with warming. In southeast, water bodies called firn aquifers form, that efficiently drain water into the ocean.
Linus Shihora, Laura Jensen, Eva Boergens, Volker Klemann, Robert Dill, Ingo Sasgen, Bert Wouters, Marius Schlaak, Jeanne Sauber-Rosenberg, Shin-Chan Han, Yoshiyuki Tanaka, Carla Braitenberg, Muhammad Tahir Javed, Gerardo Maurizio, Hugo Lecomte, Andrey Babeyko, Niels Hovius, and Henryk Dobslaw
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-576, https://doi.org/10.5194/essd-2026-576, 2026
Preprint under review for ESSD
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Satellite gravimetry measures Earth's gravity in order to track water, ice, and air redistributions across the Earth. The new ESA Earth System Model 3.0 is a simulated dataset of these mass changes and designed to perform simulation studies of upcoming satellite missions which assess their capabilities to detect various signals. The dataset includes an update of the simulated atmosphere, oceans, hydrology, solid Earth, sea-level changes, earthquakes and selected regional signals.
Judith Freienstein, Charlotte Carter, Georg-Maximilian Hüttner, Olaf Eisen, Wolfgang Szwillus, and Jörg Ebbing
EGUsphere, https://doi.org/10.5194/egusphere-2026-4746, https://doi.org/10.5194/egusphere-2026-4746, 2026
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The North East Greenland Ice Stream is a fast flowing ice stream with its formation so far inland remaining unclear. We used high-resolution bed topography data in 3D modeling to investigate its effects on geothermal heat flow (GHF). Results show local deviations of up to 20 % compared to 1D solutions. Our study highlights the importance of small-scale models to reduce uncertainty in GHF estimates to improve the understanding of ice stream dynamics.
Tsai-Wen Lin, Florian Adolphi, Hendrik Grotheer, Jens Hefter, Tommaso Tesi, Johannes Lachner, Stella Winkler, Junjie Wu, Eduardo Queiroz Alves, and Gesine Mollenhauer
EGUsphere, https://doi.org/10.5194/egusphere-2026-4726, https://doi.org/10.5194/egusphere-2026-4726, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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We refined the age-depth models of marine sediment cores from the western Laptev Sea shelf using authigenic 10Be/9Be ratios. Pre-depositional 14C ages of terrigenous biomarkers in the cores revealed distinct transport pathways. n-C28:0 fatty acids exhibited varied sources/transport mechanisms between periods strongly influenced by coastal erosion and river discharge, whereas n-alkanes suggested aged permafrost as the dominant source.
Hartmut Heinrich and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-896, https://doi.org/10.5194/egusphere-2026-896, 2026
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To date, models have not been very successful in linking Heinrich events (He) with Dansgaard-Oeschger (D-O) cycles, nor in identifying the driver. Here, we present a concept based on CO2 exchange between the atmosphere and the ocean, and on the input of Fe-rich dust during the cold phases of the systems. Cooling trend during a D-O cycle is interrupted by a precessionally maximized Atlantic circulation causing a He. The subsequent strong release of CO₂ from the ocean triggers a D-O new cycle.
Adrien Ooms, Mathieu Casado, Sonja Wahl, Thomas Laepple, Alexandra Zuhr, Pete Akers, Ghislain Picard, Laurent Arnaud, Joel Savarino, Kira Rehfeld, Barbara Stenni, Giuliano Dreossi, Mauro Masiol, Amaelle Landais, and Valérie Masson-Delmotte
EGUsphere, https://doi.org/10.5194/egusphere-2026-4801, https://doi.org/10.5194/egusphere-2026-4801, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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This work presents new insights in the archival process of multi-annual climatic signal in the near surface firn at Concordia Station, East-Antarctica, from the new data set of high resolution stable water isotope profiles measured in a snow trench. The dated isotopic profiles covering 20 years are compared against overlapping precipitation and surface snow observations. This highlights the strong contribution of stratigraphic noise and post depositional effects to individual trench profiles.
Jochen Knies, Christian Stepanek, Simon T. Belt, Stijn De Schepper, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-4723, https://doi.org/10.5194/egusphere-2026-4723, 2026
This preprint is open for discussion and under review for Climate of the Past (CP).
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The Arctic is rapidly approaching seasonally ice-free ("blue") conditions. Using proxy data to evaluate simulations of past warm climates, we show that enhanced ocean mixing substantially improves agreement with evidence for a blue Arctic and reveals multiple pathways for Arctic warming during the Early Pliocene. Our findings highlight the importance of accurately representing ocean processes in climate models to improve projections of future Arctic climate.
Julia Pfeffer, Benoît Meyssignac, Rory Bingham, Alejandro Blazquez, Marie Bouih, Carla Braitenberg, Luca Brocca, Henryk Dobslaw, Ramiro Ferrari, Ehsan Forootan, Helena Gerdener, Muhammad Tahir Javed, Laura Jensen, Volker Klemann, Anna Kremer, Jürgen Kusche, Gilles Larnicol, Muhammad Usman Liaqat, Francesco Leopardi, Elisavet-Maria Mamagiannou, Gerardo Maurizio, Roland Pail, Isabelle Panet, Thomas Papanikolaou, Peyman Saemian, Ingo Sasgen, Maike Schumacher, Marius Schlaak, Linus Shihora, Alireza Sobouti, Nico Sneeuw, Mohammad Javad Tourian, Dimitrios Tsoulis, Georgios Vergos, Bert Wouters, Fan Yang, and Ilias Daras
EGUsphere, https://doi.org/10.5194/egusphere-2026-4642, https://doi.org/10.5194/egusphere-2026-4642, 2026
This preprint is open for discussion and under review for Earth Observation (EO).
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The ESA SING project demonstrates how the future satellite gravity missions NGGM and MAGIC will improve observations of continental water storage, oceans, glaciers, sea level, earthquakes, and climate change. Their more accurate, higher-resolution gravity measurements will enhance Earth system monitoring, improve climate and hazard assessments, and strengthen operational services for water management, disaster preparedness, and environmental decision-making.
Natalie J. Burls, Nicky M. Wright, R. Paul Acosta, Catherine D. Bradshaw, Edward Gasson, Lennert B. Stap, Gilles Ramstein, Anna Ruth W. Halberstadt, Agatha M. De Boer, Funda Akgün, David J. Cantrill, Manuel Casas-Gallego, Nela Doláková, Boglarka Erdei, Alex Farnsworth, Sarah Feakins, Ran Feng, Tamara Fletcher, Frédéric Fluteau, J. A. Mattias Green, Anna S. von der Heydt, Matthew Huber, David K. Hutchinson, Dimiter Ivanov, Mine Sezgül Kayseri-Özer, Gregor Knorr, Marianna Kováčová, Caroline H. Lear, Allegra N. LeGrande, Shufeng Li, Xiaoqing Liu, Daniel J. Lunt, Katrin Meissner, Yunfa Miao, Trusha J. Naik, Javier B. Navarro, Joseph B. Novak, Diana Ochoa, Guy J.G. Paxman, Matthew J. Pound, James W. B. Rae, Tammo Reichgelt, Martin Renoult, Francesca Sangiorgi, Anta-Clarisse Sarr, Diane Segalla, Pierre Sepulchre, Amelia Shevenell, Sebastian Steinig, Eivind Straume, Caroline A. E. Strömberg, Clay Tabor, Torsten Utescher, Julia E. Weiffenbach, Elżbieta Worobiec, Yurui Zhang, Feng Zhu, Jiang Zhu, Alexandra Auderset, Florence Colleoni, Aisling Dolan, Rachel Havranek, Ann Holbourn, Nicholas Herold, Daeun Lee, James W. Marschalek, Bryce Mitsunaga, Sevi Modestou, Lina Perez-Angel, Mae Saslaw, Sinda Sosdian, Elena Stiles, Yong Sun, Ning Tan, Zhongshi Zhang, and Yan Zhao
EGUsphere, https://doi.org/10.5194/egusphere-2026-3595, https://doi.org/10.5194/egusphere-2026-3595, 2026
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Simulating warm paleoclimates increases our understanding of the mechanisms that drive climatic change and tipping points. The Miocene Epoch, specifically the Miocene Climatic Optimum, has been identified as a particularly valuable past warm climate to simulate, meriting the design of a coordinated Miocene Model Intercomparison Project. Here we synthesize the latest available literature and present the experimental design for coordinated Miocene simulations and sensitivity studies.
Rebecca Schlegel, Johannes Noll, Leah Sopie Muhle, Christian T. Wild, Falk M. Oraschewski, Olaf Eisen, and Reinhard Drews
EGUsphere, https://doi.org/10.5194/egusphere-2026-3900, https://doi.org/10.5194/egusphere-2026-3900, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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Step-like terraces at the base of Antarctic ice shelves are known from warm-water settings, but we show for the first time that they also occur at the base of a cold-water ice shelf. Repeat radar observations reveal that the terraces melt slowly and remain almost unchanged over one year. Our results suggest they form near the grounding line and are then transported with the flowing ice while melting only slowly.
Aman Akeerath Mundanatt, Silvia Vidal-Melgosa, Leonard Rößler, Kevin W. Becker, Juliane Müller, and Jan-Hendrik Hehemann
EGUsphere, https://doi.org/10.5194/egusphere-2026-4401, https://doi.org/10.5194/egusphere-2026-4401, 2026
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Marine algae convert carbon dioxide to sugars by photosynthesis in the ocean. Some complex sugars like fucoidans produced by brown algae, and diatoms, form particles and are transported to the seafloor. In this study, we were able to isolate and quantify fucoidans using a combination of various analytical methods. This approach revealed to us that fucoidans are preserved in the Bransfield Strait sediments, thereby removing carbon for 11800 years.
Xiaoxu Shi, Xiya Liu, Jiping Liu, Martin Werner, Hu Yang, Francisco W. Cruz, Chaoyuan Yang, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-3894, https://doi.org/10.5194/egusphere-2026-3894, 2026
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Cave stalagmites record the oxygen isotope of past rainfall and are used to reconstruct how monsoons changed, but due to the complexity of isotope impacting factors, what these records tell us is debated. We performed a 8300-year simulation with an isotope-enabled climate model, and show that rainfall amount is the key stable driver across global monsoons, while temperature and moisture pathways vary with region and time. Single-site records are noisy, but regional averages recover the signal.
Patrick C. Taylor, Armin Sorooshian, Rei Ueyama, Sebastian Schmidt, Ihab Abboud, Quincy Allison, Kevin Barry, Sebastian Becker, Holly A. Bender, Joseph R. Bennett, James B. Blair, Niklas Bohn, Linette Boisvert, Matthew D. Brown, Roelof Bruintjes, Anthony Bucholtz, Megan Buzanowicz, Brian Cairns, Filippo Calì Quaglia, Eduard Chemyakin, Bo Chen, Gao Chen, Hong Chen, Yu-Wen Chen, Zezhen Cheng, Swarup China, Dan Chirica, Yonghoon Choi, Peter Colarco, Brian Collister, Ewan Crosbie, Maurice J. Cross, Janet Daniels, Paul DeMott, Joshua P. DiGangi, Alcide Giorgio di Sarra, Glenn S. Diskin, Erica K. Dolinar, Eva-Lou Edwards, Samuel Ephraim, Nikolaos Evangeliou, Romanos Foskinis, Francesca Gallo, Lan Gao, José Luis Gómez-Amo, Daisy Gonzalez, Christine Groot Zwaaftink, Pawan Gupta, Ivan Heckman, Michael Hendrickson, Miguel Ricardo A. Hilario, Ken Hirata, Michelle Hofton, Andrew L. Holen, Ulas Im, Alia L. Khan, Ralph Kahn, Alexei V. Korolev, Sonia Kreidenweis, Thomas Krumpen, Nathan Kurtz, Leslie Lait, Bradley Lamkin, Jack Landy, Nurun Nahar Lata, Paul Lawson, Samuel LeBlanc, Sean Leavor, Jing Li, Thorsten Markus, Hal Maring, Andreas H. Massling, Camille Mavis, Flynn McGinnity, Kerry Meyer, Gabriel Mojica, Richard H. Moore, Parker Morris, Giovanni Muscari, Vikas Nataraja, Amin R. Nehrir, Athanasios Nenes, Edward P. Nowottnick, Matteo Ottaviani, Chelsea Parker, Ryan Patnaude, Michael Perez, Russell J. Perkins, Colten Peterson, Alek Petty, Stevie Phothisane, Chris Polashenski, Kerri A. Pratt, Kayla M. Preisler, John Prytherch, David Rabine, Jens Redemann, Ju-Mee Ryoo, Joseph S. Schlosser, Vanessa Selimovic, Michael A. Shook, Morgan Silverman, Henrik Skov, Alexander Smirnov, Cassidy Soloff, Amy Solomon, Snorre Stamnes, Azusa Takeishi, David R. Thompson, K. Lee Thornhill, Rachel Tilling, Michael Tjernström, Monica Tosco, Pedro C. Valdelomar, David Van Gilst, Jian Wang, Zhien Wang, Andrzej Wasilewski, Manfred Wendisch, Brent Wilder, Edward L. Winstead, Albert Wu, Peng Xian, Lauren M. Zamora, Jiaoshi Zhang, Lei Zhang, Lu Zhang, Luke Ziemba, and Paquita Zuidema
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-241, https://doi.org/10.5194/essd-2026-241, 2026
Preprint under review for ESSD
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This article summarizes the data sets collected during the Arctic Radiation Cloud aerosol Sea ice Interaction eXperiment (ARCSIX), NASA's most comprehensive Arctic field campaign to date. The overarching goal was to quantify the contributions of surface, clouds, aerosol particles, and precipitation to summer sea ice melt. This paper describes the ARCSIX implementation including the flight strategy, instruments, complementary data sets, access, and usage details.
Monica Ionita and Viorica Nagavciuc
EGUsphere, https://doi.org/10.5194/egusphere-2026-4179, https://doi.org/10.5194/egusphere-2026-4179, 2026
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The June 2026 heatwave set a new benchmark for early-summer heat extremes in Germany, culminating in a provisional national record of 41.8 °C and ranking first in the 1951–2026 gridded record for peak daily maximum temperature, cumulative heatwave intensity, and number of days exceeding 30 °C. Regional temperature anomalies exceeded up to 4.9 standard deviations at the federal-state level and 3.7 standard deviations at long-term stations.
Julien Meloche, Melody Sandells, Henning Löwe, Nick Rutter, Ghislain Picard, Richard Essery, Randall K. Scharien, Alexandre Langlois, Matthias Jaggi, Josh King, Peter Toose, Michele Scagliola, Jerome Bouffard, Alessandro Di Bella, and Christian Haas
EGUsphere, https://doi.org/10.5194/egusphere-2026-3615, https://doi.org/10.5194/egusphere-2026-3615, 2026
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Sea ice thickness is essential for climate studies. Radar altimetry has provided sea ice thickness measurements, but uncertainty arises from the interaction of the signal with the snow cover. Therefore, modelling the signal interaction with the snow is necessary to improve retrieval. A radar model was used to simulate the radar signal from the snow-covered sea ice. This work paved the way to improved physical algorithms to retrieve snow depth and sea ice thickness for radar altimeter missions.
Tobias Spiegl, Norel Rimbu, Franziska Kappenberger, Xiaojie Hao, Wenjuan Huo, Stephan Thober, Ulrike Langematz, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-3630, https://doi.org/10.5194/egusphere-2026-3630, 2026
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Natural solar signals are not fixed in time. During past centennial-scale solar minima, reduced solar activity promoted summer heavy precipitation through coupled changes in ozone, sea ice and storm tracks. In a warmer future climate, this pathway weakens, showing that anthropogenic warming can reshape how natural forcings translate into regional weather extremes.
Clemens Schannwell, Marie-Luise Kapsch, Matteo Willeit, Lars Ackermann, Gregor Knorr, Uta Krebs-Kanzow, Gerrit Lohmann, Katharina D. Six, Christian Stepanek, and Uwe Mikolajewicz
EGUsphere, https://doi.org/10.5194/egusphere-2026-3384, https://doi.org/10.5194/egusphere-2026-3384, 2026
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We present long-term future projections of the Greenland ice sheet based on three numerical models which all explicitly account for feedbacks between the climate and the Greenland ice sheet. We find that projections vary considerably across the models, particularly beyond 2100. The main reasons for this is the different modelled climate as well as how the modelled climate is translated into snowfall and melt in each of the models.
Emma Pearce, Dimitri Zigone, Coen Hofstede, Andreas Fichtner, and Olaf Eisen
EGUsphere, https://doi.org/10.5194/egusphere-2026-3762, https://doi.org/10.5194/egusphere-2026-3762, 2026
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When ice cores are drilled, they are broken before being brought back to the surface, generating small seismic signals. We tested whether these signals could be used to study the inside of the North East Greenland Ice Stream. Most possible signals were too weak or noisy, but a few clear examples produced realistic estimates of ice speed. The results show that this method is promising, but future experiments need better timing, quieter conditions, and sensors placed specifically for this purpose.
Janina Güntzel, Juliane Müller, Ralf Tiedemann, Gesine Mollenhauer, Lester Lembke-Jene, Estella Weigelt, Lasse Schopen, Niklas Wesch, Laura Kattein, Andrew N. Mackintosh, and Johann P. Klages
The Cryosphere, 20, 3739–3758, https://doi.org/10.5194/tc-20-3739-2026, https://doi.org/10.5194/tc-20-3739-2026, 2026
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Combined multi-proxy sediment core analyses and bathymetry data reveal the deglaciation along the Mac. Robertson Shelf, a yet insufficiently studied sector of the East Antarctic margin. Grounding line extent towards the continental shelf break prior to ~12.7 cal. ka BP and subsequent episodic mid-shelf retreat until the early Holocene prevented Dense Shelf Water formation in its current form, hence suggesting a different formation mechanism under such full glacial conditions.
Neil Ross, Rebecca J. Sanderson, Bernd Kulessa, Martin Siegert, Guy J. G. Paxman, Keir A. Nichols, Matthew R. Siegfried, Stewart S. R. Jamieson, Michael J. Bentley, Tom A. Jordan, Christine L. Batchelor, David Small, Olaf Eisen, Kate Winter, Robert G. Bingham, S. Louise Callard, Rachel Carr, Christine F. Dow, Helen A. Fricker, Emily Hill, Benjamin H. Hills, Coen Hofstede, Hafeez Jeofry, Felipe Napoleoni, and Wilson Sauthoff
The Cryosphere, 20, 3705–3737, https://doi.org/10.5194/tc-20-3705-2026, https://doi.org/10.5194/tc-20-3705-2026, 2026
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We review research about a group of fast-flowing Antarctic ice streams, the Foundation-Patuxent-Academy System. Previously, we knew little about how these ice streams flow, how they interact with each other and the ocean, what their geological history was, and how they might evolve in a warming world. By reviewing existing research, we have identified the future research needed to determine how these ice streams function, and how they might contribute to future global sea level rise.
Fyntan Shaw, Torben Kunz, and Thomas Laepple
EGUsphere, https://doi.org/10.5194/egusphere-2026-3558, https://doi.org/10.5194/egusphere-2026-3558, 2026
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Estimates of water isotope diffusion lengths in ice cores are used to correct signal loss and infer past firn temperatures, but require accurate spectral fitting. Existing methods neglect effects from discrete sampling, causing an estimation bias which we demonstrate grows with sampling interval and decreasing diffusion length. By incorporating sampling effects into the model fit, we derive an unbiased estimator that improves estimates from coarse data and ice cores with small diffusion lengths.
Heikki Järvinen, Jouni Räisänen, Lauri Tuppi, Clément Bouvier, Antonio Sanchez-Benitez, Juniper Tyree, Antti Toropainen, Paolo Davini, Francisco Doblas-Reyes, Thomas Jung, Daniel Klocke, Jenni Kontkanen, Sebastian Milinski, Matteo Nurisso, Himansu Kesari Pradhan, and Irina Sandu
EGUsphere, https://doi.org/10.5194/egusphere-2026-3364, https://doi.org/10.5194/egusphere-2026-3364, 2026
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There is rich process-level variability present in the new-generation kilometre-scale climate simulations. The EU’s Climate Change Adaptation Digital Twin (Climate DT) integrates global Earth observing systems and observation modelling capabilities – until now common only in weather prediction – into operational climate simulation workflow. This provides a novel framework for precise evaluation of fine-scale details of simulation data and informing adaptation decisions at local (city) scales.
Daniel Abele, Thomas Kleiner, Yannic Fischler, Benjamin Uekermann, Gerasimos Chourdakis, Mathieu Morlighem, Achim Basermann, Christian Bischof, Hans-Joachim Bungartz, and Angelika Humbert
Geosci. Model Dev., 19, 5019–5039, https://doi.org/10.5194/gmd-19-5019-2026, https://doi.org/10.5194/gmd-19-5019-2026, 2026
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Accurate simulations of ice-sheet evolution require a multi-physics approach that captures the interaction between glaciers and their subglacial environment. For this purpose, we have extended ice sheet and subglacial hydrology models using a coupling library. This simplifies coupled Earth systems simulations by allowing models to interact with minimal effort and computational expense. We have evaluated the solution regarding performance and choice of coupling library.
Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-3085, https://doi.org/10.5194/egusphere-2026-3085, 2026
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Climate models often simplify Earth’s atmosphere and oceans to make complex calculations possible. This study examines how such simplifications can unintentionally change the mathematical structures that determine large-scale climate variability and wave behavior. Using examples from global temperature balance and ocean–atmosphere waves, the paper shows that some common approximations may alter the set of physically allowed patterns of variability rather than simply simplifying them.
Rebecca McPherson, Wilken-Jon von Appen, Laura de Steur, Luise Becker, Monica Ionita, Thomas Krumpen, Gunnar Spreen, and Finn Ole Heukamp
EGUsphere, https://doi.org/10.5194/egusphere-2026-2955, https://doi.org/10.5194/egusphere-2026-2955, 2026
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The East Greenland Current carries cold, fresh water and sea ice from the Arctic toward the North Atlantic. Using seven years of ocean measurements off northeast Greenland, we found that the current occasionally develops a northward component on the continental slope that can persist for weeks. These events are driven by specific wind patterns that reorganise the current and push warm water into the Arctic — a previously unknown heat pathway, which has regional consequences for sea ice.
Adrien Ooms, Mathieu Casado, Ghislain Picard, Laurent Arnaud, Maria Hörhold, Andrea Spolaor, Rita Traversi, Joel Savarino, Patrick Ginot, Pete Akers, Birthe Twarloh, and Valérie Masson-Delmotte
The Cryosphere, 20, 3235–3255, https://doi.org/10.5194/tc-20-3235-2026, https://doi.org/10.5194/tc-20-3235-2026, 2026
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This work presents a new approach to the estimation of accumulation rates at Concordia Station, East-Antarctica, for the last 20 years, from a new data set of chemical tracers and snow micro-scale properties measured in a snow trench. Multi-annual and meter to decameter scale variability of accumulation rates are compared again in-situ measurements of surface laser scanner and stake farm, with very good agreement. This further constrains SMB estimation for Antarctica at high temporal resolution.
Rohit Ghosh, Suvarchal Kumar Cheedela, Sebastian Beyer, Nikolay Koldunov, Stella Berzina, Audrey Delpech, Svetlana Loza, Chathurika Wikramage, Stephy Libera, Matthias Aengenheyster, Amal John, Armelle Remedio, Patrick Scholz, Dmitry Sidorenko, Jan Streffing, Fabian Wachsmann, and Thomas Jung
EGUsphere, https://doi.org/10.5194/egusphere-2026-1289, https://doi.org/10.5194/egusphere-2026-1289, 2026
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Understanding climate change requires detailed computer simulations of the Earth system. Here we present one of the first century-long global simulations in which both the atmosphere and ocean are represented at kilometre-scale resolution. Such simulations are extremely computationally demanding, but we demonstrate their feasibility and show that they can capture key climate patterns while representing important small-scale ocean processes.
James R. Jordan, Frank Pattyn, Daniel Abele, Torsten Albrecht, Jorge Alvarez-Solas, Jowan M. Barnes, Tijn Berends, Jorge A. Bernales, Javier Blasco, Gong Cheng, Youngmin Choi, Stephen L. Cornford, Cruz Garcia-Molina, Fabien Gillet-Chaulet, G. Hilmar Gudmundsson, Angelika Humbert, Gunter R. Leguy, William H. Lipscomb, Marisa Montoya, Daniel Moreno-Parada, Mathieu Morlighem, Tyler Pelle, Alexander Robinson, Martin Rückamp, Hélène Seroussi, Yanmei Tian, Luisa Wagner, Roderick S. W. van de Wal, Liyun Zhao, and Thomas Zwinger
EGUsphere, https://doi.org/10.5194/egusphere-2026-1962, https://doi.org/10.5194/egusphere-2026-1962, 2026
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Ice calving is a recent inclusion in ice sheet models and there has not been a systematic test of how well it has been implemented. We show that models can accurately represent a given rate of ice calving, properties at the ice front evolve smoothly during calving, and that there are no consistent differences in ice behaviour between various approaches to representing calving in numerical ice models. This gives us confidence in their ability for use in sea level rise prediction simulations.
Jannis Viola, Lars Wörmer, Kai-Uwe Hinrichs, and Thomas Laepple
Clim. Past, 22, 1023–1036, https://doi.org/10.5194/cp-22-1023-2026, https://doi.org/10.5194/cp-22-1023-2026, 2026
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This study used mass spectrometry imaging (MSI) to detect spatial patterns of biomarkers used for sea surface temperature (SST) reconstructions. The observed proxy heterogeneity was bigger than expected within layered marine sediments. The data was used to estimate the climate signal content of individual MSI based reconstructions. The results can be used to inform sampling decisions or to derive uncertainty estimates for high-resolution SST reconstructions and climate variability estimates.
Albin Eriksson, Junjie Wu, Matt O'Regan, and Örjan Gustafsson
EGUsphere, https://doi.org/10.5194/egusphere-2026-2414, https://doi.org/10.5194/egusphere-2026-2414, 2026
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Sea ice is an important regulator of the Arctic climate systems. Records of sea ice past instrumental records are necessary to understand how sea ice is altered during past periods of abrupt climate change, and what consequences such changes have on the polar climates. Here, we reconstructed the sea ice cover of the East Siberian Arctic and found that the sea ice extent likely was linked to protecting/eroding permafrost coastlines during the last deglaciation.
Alessandro Gagliardi, Norel Rimbu, Gerrit Lohmann, and Monica Ionita
Clim. Past, 22, 935–955, https://doi.org/10.5194/cp-22-935-2026, https://doi.org/10.5194/cp-22-935-2026, 2026
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This study shows that stable oxygen isotope ratios from Greenland ice cores can help identify extreme winter events in Europe. In years with a lack of the heavier oxygen isotope, we found changes in the atmospheric circulation over Europe. These changes bring warmer, wetter conditions to the Norwegian coast and colder, drier conditions to southern Europe. The pattern appears in both recent and past periods, staying stable over the last 400 years.
Martina Zapponini, Tido Semmler, Jan Streffing, Thomas Rackow, Lettie A. Roach, and Thomas Jung
Geosci. Model Dev., 19, 3395–3425, https://doi.org/10.5194/gmd-19-3395-2026, https://doi.org/10.5194/gmd-19-3395-2026, 2026
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This study evaluates the impact of grid resolution on long-term present and future climate runs using the Alfred Wegener Institute global model AWI-CM3. A higher-resolution setup (35 km atmosphere, eddy-permitting/resolving ocean) improves small-scale processes and long-term variability, across variables and regions, and can capture nonlinear ocean–atmosphere interactions often missed by Coupled Model Intercomparison Project (CMIP) models.
Steven Franke, Daniel Steinhage, Veit Helm, Tobias Binder, Uwe Nixdorf, Heinrich Miller, Angelika Humbert, Daniela Jansen, Graeme Eagles, Hannes Eisermann, Wilfried Jokat, Antonia Ruppel, Reinhard Drews, Alexandra Zuhr, Amelie Driemel, Andreas Walter, Peter Konopatzky, Robin Heß, Antonie Haas, Roland Koppe, Pascal H. Andreas, and Olaf Eisen
The Cryosphere, 20, 2485–2530, https://doi.org/10.5194/tc-20-2485-2026, https://doi.org/10.5194/tc-20-2485-2026, 2026
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This review synthesizes 30 years of Alfred Wegener Institute’s (AWI) airborne radar research in Antarctica and Greenland, detailing six radar systems and their applications in studying ice dynamics, basal properties, and subglacial landscapes. Moreover, it introduces the public release of AWI's airborne radar datasets via the Radar Data over Polar Ice Sheets Viewer and PANGAEA, ensuring findable, accessible, interoperable, and reusable access for future polar research.
Yufei Liu, Hu Yang, Haowen Dang, Gerrit Lohmann, Tao Lian, Zhengyao Lu, Xiaoxu Shi, Jiping Liu, Hang Wang, Feng Jiang, Xinyue Deng, Xiaoming Hu, and Dake Chen
EGUsphere, https://doi.org/10.21203/rs.3.rs-7865695/v1, https://doi.org/10.21203/rs.3.rs-7865695/v1, 2026
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Observations and reconstructions show that ENSO is influenced by astronomical precession in addition to anthropogenic warming. Using ~10,000-year simulations, we reconstruct a full tropical precession cycle and find that present ENSO activity is relatively strong within it. This results from asymmetric continental heating that alters the background climate and the threshold for ENSO development, linking astronomical forcing to tropical climate variability.
Francisco J. Doblas-Reyes, Jenni Kontkanen, Irina Sandu, Mario Acosta, Mohammed Hussam Al Turjmam, Ivan Alsina-Ferrer, Miguel Andrés-Martínez, Costanza Anerdi, Leo Arriola, Marvin Axness, Marc Batlle Martín, Peter Bauer, Tobias Becker, Daniel Beltrán, Sebastian Beyer, Hendryk Bockelmann, Pierre-Antoine Bretonnière, Sebastien Cabaniols, Silvia Caprioli, Miguel Castrillo, Aparna Chandrasekar, Suvarchal Cheedela, Victor Correal, Emanuele Danovaro, Paolo Davini, Jussi Enkovaara, Claudia Frauen, Barbara Früh, Aina Gaya Àvila, Paolo Ghinassi, Rohit Ghosh, Supriyo Ghosh, Iker González, Katherine Grayson, Matthew Griffith, Ioan Hadade, Christopher Haine, Carl Hartick, Utz-Uwe Haus, Shane Hearne, Heikki Järvinen, Bernat Jiménez, Amal John, Marlin Juchem, Thomas Jung, Jessica Kegel, Matthias Kelbling, Kai Keller, Bruno Kinoshita, Theresa Kiszler, Daniel Klocke, Lukas Kluft, Nikolay Koldunov, Tobias Kölling, Joonas Kolstela, Luis Kornblueh, Sergey Kosukhin, Aleksander Lacima-Nadolnik, Jeisson Javier Leal Rojas, Jonni Lehtiranta, Tuomas Lunttila, Anna Luoma, Pekka Manninen, Alexey Medvedev, Sebastian Milinski, Ali Mohammed, Sebastian Müller, Devaraju Naryanappa, Natalia Nazarova, Sami Niemelä, Bimochan Niraula, Henrik Nortamo, Aleksi Nummelin, Matteo Nurisso, Pablo Ortega, Stella Paronuzzi, Xabier Pedruzo-Bagazgoitia, Charles Pelletier, Carlos Peña, Suraj Polade, Himansu Kesari Pradhan, Rommel Quintanilla, Tiago Quintino, Thomas Rackow, Jouni Räisänen, Maqsood Mubarak Rajput, René Redler, Balthasar Reuter, Nuno Rocha Monteiro, Francesc Roura-Adserias, Silva Ruppert, Susan Sayed, Reiner Schnur, Tanvi Sharma, Dmitry Sidorenko, Outi Sievi-Korte, Albert Soret, Christian Steger, Bjorn Stevens, Jan Streffing, Jaleena Sunny, Luiggi Tenorio, Stephan Thober, Ulf Tigerstedt, Oriol Tinto, Juha Tonttila, Heikki Tuomenvirta, Lauri Tuppi, Ginka Van Thielen, Emanuele Vitali, Jost von Hardenberg, Ingo Wagner, Nils Wedi, Jan Wehner, Sven Willner, Xavier Yepes-Arbós, Florian Ziemen, and Janos Zimmermann
Geosci. Model Dev., 19, 2821–2848, https://doi.org/10.5194/gmd-19-2821-2026, https://doi.org/10.5194/gmd-19-2821-2026, 2026
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The Climate Change Adaptation Digital Twin (Climate DT) pioneers the operationalisation of global climate projections. It produces global simulations with local granularity for adaptation decision-making. Applications are embedded to generate tailored indicators. A unified workflow orchestrates all components in several supercomputers. Data management ensures consistency and streaming enables real-time use. It is a complementary innovation to initiatives like CMIP, CORDEX, and climate services.
Peter Köhler, Laurie Menviel, Frerk Pöppelmeier, Timothy J. Heaton, Edouard Bard, and Luke C. Skinner
Clim. Past, 22, 729–746, https://doi.org/10.5194/cp-22-729-2026, https://doi.org/10.5194/cp-22-729-2026, 2026
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Radiocarbon (14C) is decaying over time, which is used to determine the age of carbon-containing objects. Calibration curves are necessary to come from measured 14C values to calendar ages. We use different models in order to improve future calibration curves, especially around times of abrupt changes in the Atlantic meridional overturning circulation. We find that uncertainties during those times are underrepresented in present calibrations, especially in the Atlantic.
Niklas Kappelt, Piers Larkman, Pascal Bohleber, Florian Adolphi, Marcus Christl, Christof Vockenhuber, Philip Gautschi, Eric Wolff, and Raimund Muscheler
EGUsphere, https://doi.org/10.5194/egusphere-2026-790, https://doi.org/10.5194/egusphere-2026-790, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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10Be is a radionuclide often measured in ice cores to reconstruct the solar magnetic field and geomagnetic field, as well as to date ice based on its half-life of 1.387 million years. Previous measurements in deep ice from Antarctica showed a decrease in concentrations with age. We analysed the influence of the sample preparation procedure and were able to show that the use of ion exchange columns can lead to decreasing concentrations, an effect which is amplified at greater depths and ages.
Monica Ionita, Bogdan Antonescu, and Viorica Nagavciuc
EGUsphere, https://doi.org/10.5194/egusphere-2026-1457, https://doi.org/10.5194/egusphere-2026-1457, 2026
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This study shows that the winter of 2025/26 in Romania was not historically exceptional in thermal terms, despite intense media claims to the contrary. Using long instrumental records, we show that January and February 2026 were both markedly warmer than the 1971–2000 average, while the main high-impact event, the 18th of February 2026 blizzard, was driven by a Mediterranean cyclone and strong moisture transport rather than an extreme cold outbreak.
Niklas Neckel, Niels Fuchs, Jonathan Kolar, Thomas Kordes, and Christian Haas
EGUsphere, https://doi.org/10.5194/egusphere-2026-714, https://doi.org/10.5194/egusphere-2026-714, 2026
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This study summarizes challenges of operating consumer-grade UAVs over high-latitude Arctic pack ice. High ice-floe drift and the lack of commercial grid-mission solutions north of 85° N hinder the generation of void-free orthomosaics and DEMs. We present an autonomous high-latitude grid-flight approach with pre- and post-flight drift correction, applied during ArcWatch-2 (Aug/Sep 2024), enabling ice thickness, surface type and pond depth retrievals.
Riccardo Biella, Anastasiya Shyrokaya, Ilias Pechlivanidis, Daniela Cid, Maria Carmen Llasat, Faranak Tootoonchi, Marthe Wens, Marleen Lam, Elin Stenfors, Samuel Sutanto, Elena Ridolfi, Serena Ceola, Pedro Alencar, Giuliano Di Baldassarre, Monica Ionita, Mariana Madruga de Brito, Scott J. McGrane, Benedetta Moccia, Viorica Nagavciuc, Fabio Russo, Svitlana Krakovska, Andrijana Todorovic, Patricia Trambauer, Raffaele Vignola, and Claudia Teutschbein
Nat. Hazards Earth Syst. Sci., 26, 955–979, https://doi.org/10.5194/nhess-26-955-2026, https://doi.org/10.5194/nhess-26-955-2026, 2026
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This research by the Drought in the Anthropocene (DitA) network highlights the crucial role of forecasting systems and Drought Management Plans in European drought risk management. Based on a survey of water managers during the 2022 European drought, it underscores the impact of preparedness on response and the evolution of drought management strategies across the continent, showing how organisations with preparedness measures in place responded faster and more effectively.
Julien A. Bodart, Vjeran Višnjević, Steven Franke, Veit Helm, Olaf Eisen, Antoine Hermant, Alexandra M. Zuhr, Daniel Steinhage, and Johannes C. R. Sutter
The Cryosphere, 20, 1379–1404, https://doi.org/10.5194/tc-20-1379-2026, https://doi.org/10.5194/tc-20-1379-2026, 2026
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We used radar data and computer models to study layers within Antarctic ice that record past snowfall and ice-sheet changes. These layers, called isochrones, are seldomly used to model Antarctica’s past. By comparing radar observations with simulations, we show how they can greatly improve model accuracy and provide two new datasets to help refine future reconstructions of Antarctic ice evolution.
Mirko Scheinert, Weisen Shen, Richard C. Aster, Lambert Caron, Michael D. Hartinger, Matt A. King, Andrew Lloyd, Anya M. Reading, J. Paul Winberry, Terry Wilson, Lucilla Alfonsi, Michael J. Bentley, Eric Buchta, Thomas Y. Chen, Peter J. Clarke, Jörg Ebbing, Olaf Eisen, Natalya Gomez, Esra Günaydın, Samantha Hansen, Erik R. Ivins, Achraf Koulali, Grace A. Nield, Frederick Richards, Mahmut O. Selbesoglu, Stephanie Sherman, Pippa L. Whitehouse, and Matthias Willen
EGUsphere, https://doi.org/10.5194/egusphere-2025-6370, https://doi.org/10.5194/egusphere-2025-6370, 2026
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With an ongoing mass loss the Antarctic Ice Sheet contributes to global-mean sea level rise at a rate of 0.4 mm/a. Thus, it plays a key role in global climate and provides a natural laboratory to study processes that interlink cryosphere, solid Earth, atmosphere and ocean. We discuss how GNSS and seismic networks in Antarctica were used to significantly advance our understanding of these processes, and how they should be maintained and extended to answer key science questions in the future.
Lianne Sijbrandij, Uta Krebs-Kanzow, Paul Gierz, Gregor Knorr, Lu Niu, Shan Xu, and Gerrit Lohmann
EGUsphere, https://doi.org/10.22541/essoar.174861028.86292675/v2, https://doi.org/10.22541/essoar.174861028.86292675/v2, 2026
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Towards the end of the last ice age large proglacial lakes formed at the margins of the retreating ice sheets, staying cold due to the influence of melting ice. Modeling shows these lakes lowered summer air temperatures, increased snowfall, and in total reduced surface melt by 18–27 % for nearby ice sheets. If lakes stayed below 4 °C, melt dropped by 23–35 %, providing a substantial negative feedback for retreating of ice sheets.
Alejandra Quintanilla-Zurita, Benjamin Rabe, Claudia Wekerle, Torsten Kanzow, Ivan Kuznetsov, Sinhue Torres-Valdes, Enric Pallàs-Sanz, and Ying-Chih Fang
Ocean Sci., 22, 305–328, https://doi.org/10.5194/os-22-305-2026, https://doi.org/10.5194/os-22-305-2026, 2026
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During a year-long Arctic expedition, we discovered nine underwater eddies beneath the sea ice in the central Arctic Ocean. These hidden structures form within a layered part of the ocean just below the surface and may reshape water layers and transport heat, freshwater, and nutrients. Using drifting ice platforms, we measured their size, depth, and motion to understand how they form.
Jonathan Fipper, Jakob Abermann, Ingo Sasgen, Henrik Skov, Lise Lotte Sørensen, and Wolfgang Schöner
The Cryosphere, 20, 683–698, https://doi.org/10.5194/tc-20-683-2026, https://doi.org/10.5194/tc-20-683-2026, 2026
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We use measurements conducted with uncrewed aerial vehicles (UAVs) and reanalysis data to study the drivers of vertical air temperature structures and their link to the surface mass balance of Flade Isblink, a large ice cap in Northeast Greenland. Surface properties control temperature structures up to 100 m above ground, while large-scale circulation dominates above. Mass loss has increased since 2015, with record loss in 2023 associated with frequent synoptic conditions favouring melt.
Alessandro Cotronei, Ulrike Feudel, and Angelika Humbert
EGUsphere, https://doi.org/10.5194/egusphere-2025-6334, https://doi.org/10.5194/egusphere-2025-6334, 2026
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We construct a mathematical model to describe the formation of lakes on the Greenland Ice Sheet across multiple years. The model represents the dynamics of ice, snow, and surface water, accounting for the influence of air temperature. Our results indicate that lakes can enhance ice melt by absorbing sunlight, thereby accelerating the loss of Greenland ice under realistic scenarios of temperature increase.
Valentin Ludwig, Caroline Ribere, Sara Fleury, Christian Haas, Michel Tsamados, Mahmoud El Hajj, Jerome Bouffard, Michele Scagliola, Marion Bocquet, Eric de Boisseson, Vincent Boulenger, Guillaume Boutin, Laurence Connor, Léo Edel, Stefan Hendricks, Ferran Hernández Macià, Marcus Huntemann, Lars Kaleschke, Frank Kauker, Jack Landy, Tom Megain, Alek Petty, Till Soya Rasmussen, Mads Hvid Ribergaard, Robert Ricker, Axel Schweiger, Hoyeon Shi, Xiangshan Tian-Kunze, Donghui Yi, and Alessandro Di Bella
EGUsphere, https://doi.org/10.5194/egusphere-2025-6201, https://doi.org/10.5194/egusphere-2025-6201, 2026
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Our paper compares Arctic sea-ice thickness datasets from models, reanalyses, satellite-only, and multi-product sources. We validate them against Beaufort Sea reference data, compare large-scale products, and analyse time series. Cross-product biases range from 0.2–0.4 m, RMSDs from 0.4–0.9 m, and correlations from 0.5–0.8. We find no 2010–2023 trend, but 1995–2023 thinning of ~ 0.5 m in November and ~ 0.3 m in March.
Ruijian Gou, Yaocheng Deng, Yingzhe Cui, Qi Shu, Hong Wang, Shengpeng Wang, Lixin Wu, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-5296, https://doi.org/10.5194/egusphere-2025-5296, 2025
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Under anthropogenic warming, Arctic warming is nearly four times faster than global average. One key reason is the ice-albedo feedback – sea ice melting reveals the darker ocean water, which absorbs more solar radiation. Using a climate model of more refined grids, we find that the ocean absorbs more solar radiation. We attribute it to the better represented short-term extreme ocean warming events. They cause more short-term sea ice melting, allowing the ocean to absorb more solar radiation.
Arnaud Nicolas, Jens Hefter, Hendrik Grotheer, Tommaso Tesi, Ruediger Stein, Alessio Nogarotto, Eduardo Queiroz Alves, and Gesine Mollenhauer
Clim. Past, 21, 2579–2599, https://doi.org/10.5194/cp-21-2579-2025, https://doi.org/10.5194/cp-21-2579-2025, 2025
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We analyzed a high-resolution marine sediment record from the Laptev Sea to reconstruct deglacial permafrost thaw events during the last 16 kyr. Using biomarkers and radiocarbon dating, we found that peaks in pre-aged terrigenous material coincided with rapid sea-level rise, indicating coastal erosion as the main mobilization mechanism. This research provides insights into past permafrost carbon release, informing predictions of future climate-permafrost feedback in a warming world.
Kshema Shaju, Thomas Laepple, Nora Hirsch, and Peter Zaspel
Geosci. Instrum. Method. Data Syst., 14, 459–474, https://doi.org/10.5194/gi-14-459-2025, https://doi.org/10.5194/gi-14-459-2025, 2025
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We present a method to optimize the number and placement of temperature sensors in the borehole for borehole thermometry. Based on heat transfer model simulations, a greedy algorithm chooses sensor locations that minimize sampling errors. Applications in Antarctic and Greenland boreholes show this method outperforms traditional linear and exponential spacing, reducing errors up to tenfold. This approach offers an efficient, cost-effective solution to improve subsurface temperature monitoring.
Lena G. Buth, Thomas Krumpen, Niklas Neckel, Melinda A. Webster, Gerit Birnbaum, Niels Fuchs, Philipp Heuser, Ole Johannsen, and Christian Haas
The Cryosphere, 19, 6527–6545, https://doi.org/10.5194/tc-19-6527-2025, https://doi.org/10.5194/tc-19-6527-2025, 2025
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Arctic sea ice is becoming smoother, raising the question of how these changes affect melt pond coverage and thereby surface albedo. Using airborne imagery and laser altimeter data, we investigated how pressure ridges influence melt ponds. The presence of ridges does not directly control pond fraction, but it does influence pond size distribution and pond geometry. Small ponds have a more complex shape on rough ice than on smooth ice, while the opposite is true for large ponds.
Steven Franke, Mara Neudert, Veit Helm, Arttu Jutila, Océane Hames, Niklas Neckel, Stefanie Arndt, and Christian Haas
The Cryosphere, 19, 6319–6339, https://doi.org/10.5194/tc-19-6319-2025, https://doi.org/10.5194/tc-19-6319-2025, 2025
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Our research explored how icebergs affect the distribution of snow and flooding on Antarctic coastal sea ice. Using aircraft-based radar and laser scanning, we found that icebergs create thick snow drifts on their wind-facing sides and leave snow-free zones in their lee. The weight of these snow drifts often causes the ice below to flood, forming slush. These patterns, driven by wind and iceberg placement, are crucial for understanding sea ice changes and improving climate models.
Valerie Reppert, Olaf Eisen, Holger Schmithüsen, Stefanie Arndt, Guido Ascenso, Linda Ort, and Zsófia Jurányi
EGUsphere, https://doi.org/10.5194/egusphere-2025-5199, https://doi.org/10.5194/egusphere-2025-5199, 2025
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We analyzed 33 years of snow accumulation measurements at Neumayer Station, Antarctica, to understand changes in the amount of snow building up on the surface over time. The long-term, high-resolution data show mostly stable accumulation, but rare positive extremes appeared in 2021 and 2023. Seasonal and multi-year patterns were identified, providing valuable data to improve climate models and satellite observations.
Fernanda DI Alzira Oliveira Matos, Dmitry Sidorenko, Xiaoxu Shi, Lars Ackermann, Janini Pereira, Gerrit Lohmann, and Christian Stepanek
Ocean Sci., 21, 2895–2914, https://doi.org/10.5194/os-21-2895-2025, https://doi.org/10.5194/os-21-2895-2025, 2025
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The Atlantic Meridional Overturning Circulation (AMOC) is responsible for about 25 % of the poleward ocean heat transport. Currently, the AMOC strength is mostly calculated in depth space (z-AMOC). However, we argue that, in warmer climates, the AMOC should be calculated in density space (ρ-AMOC). We performed simulations with CO2 forcing of 280 ppmv (PI) and 1120 ppmv of (4xCO2) and find that ρ-AMOC provides more physical and meaningful information about the AMOC in warmer climates.
Riccardo Biella, Anastasiya Shyrokaya, Monica Ionita, Raffaele Vignola, Samuel J. Sutanto, Andrijana Todorovic, Claudia Teutschbein, Daniela Cid, Maria Carmen Llasat, Pedro Alencar, Alessia Matanó, Elena Ridolfi, Benedetta Moccia, Ilias Pechlivanidis, Anne van Loon, Doris E. Wendt, Elin Stenfors, Fabio Russo, Jean-Philippe Vidal, Lucy Barker, Mariana Madruga de Brito, Marleen Lam, Monika Bláhová, Patricia Trambauer, Raed Hamed, Scott J. McGrane, Serena Ceola, Sigrid J. Bakke, Svitlana Krakovska, Viorica Nagavciuc, Faranak Tootoonchi, Giuliano Di Baldassarre, Sandra Hauswirth, Shreedhar Maskey, Svitlana Zubkovych, Marthe Wens, and Lena M. Tallaksen
Nat. Hazards Earth Syst. Sci., 25, 4475–4501, https://doi.org/10.5194/nhess-25-4475-2025, https://doi.org/10.5194/nhess-25-4475-2025, 2025
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The DitA (Drought in the Anthropocene) network's study on the 2022 European drought reveals growing risks, varied impacts, and fragmented, short-term management. Based on a survey of water managers, it explores risk, impacts, strategies, and their evolution. While challenges persist, signs of improvement show readiness for change. The authors call for a European Drought Directive to unify and guide future drought risk management.
Mara Y. McPartland, Thomas Münch, Andrew M. Dolman, Raphaël Hébert, and Thomas Laepple
Clim. Past, 21, 1917–1931, https://doi.org/10.5194/cp-21-1917-2025, https://doi.org/10.5194/cp-21-1917-2025, 2025
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Paleoclimate proxy records contain a combination of climate signals and non-climatic noise. This noise can affect year-to-year variations, or introduce uncertainty on medium and long timescales. Proxies contain different types, or "colors" of noise stemming from the diverse physical and biological processes that go into their creation. We show how non-climatic noise affects tree rings, corals and ice cores. We aim to improve representations of noise in paleoclimate research activities.
Charlotte M. Carter, Steven Franke, Daniela Jansen, Chris R. Stokes, Veit Helm, John Paden, and Olaf Eisen
The Cryosphere, 19, 5299–5315, https://doi.org/10.5194/tc-19-5299-2025, https://doi.org/10.5194/tc-19-5299-2025, 2025
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The subglacial landforms beneath actively fast-flowing ice in Greenland have not been explored in detail, as digital elevation models have not had a high enough resolution to see these features. We use swath radar imaging to visualise landforms at the onset of an ice stream, revealing mega-scale glacial lineations, that would usually be assumed to be indicative of faster ice flow than the current velocities. Interpretation of the landscape also gives an indication of the properties of the bed.
Paul D. Bons, Yuanbang Hu, M.-Gema Llorens, Steven Franke, Nicolas Stoll, Ilka Weikusat, Julien Westhoff, and Yu Zhang
The Cryosphere, 19, 5095–5109, https://doi.org/10.5194/tc-19-5095-2025, https://doi.org/10.5194/tc-19-5095-2025, 2025
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What causes folds in ice layers from the km scale down to the scale visible in the drill core: buckle folding due to variations in viscosity between layers, or the effect of mechanical anisotropy of ice due to an alignment of the crystal-lattice planes? Power spectra of folds in ice, a biotite schist, and numerical simulations show that folding in ice is due to the anisotropy, as the folds are self-similar, meaning that there is no characteristic fold scale that would result from buckle folding.
Florian Painer, Sepp Kipfstuhl, Martyn Drury, Tsutomu Uchida, Johannes Freitag, and Ilka Weikusat
The Cryosphere, 19, 5023–5044, https://doi.org/10.5194/tc-19-5023-2025, https://doi.org/10.5194/tc-19-5023-2025, 2025
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Air clathrate hydrates trap ancient air in the deeper part of ice sheets. We use digital microscopy and automated image analysis to investigate the evolution of number, size, and shape of air clathrate hydrates from 1250 m depth to the bottom of the ice sheet. We confirm the previously found relation of changes in number and size with past climate and find a connection of their shape to changes in ice deformation. The results will help us to better understand air clathrate hydrates in deep ice.
Fyntan Shaw, Thomas Münch, Vasileios Gkinis, and Thomas Laepple
The Cryosphere, 19, 4913–4928, https://doi.org/10.5194/tc-19-4913-2025, https://doi.org/10.5194/tc-19-4913-2025, 2025
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Diffusion in combination with measurement noise erase high-frequency water isotope variability in ice cores, linking measurement precision to recoverable resolution. We derive expressions for this relationship, finding a resolution improvement of 1.5 times for a 10-fold measurement noise reduction. Based on the current age-depth model, our method predicts 10 000-year cycles will be recoverable in the 1.5 Myr old ice from the Oldest Ice Core δ18O record if a noise level of 0.01 ‰ is achieved.
Hans Segura, Xabier Pedruzo-Bagazgoitia, Philipp Weiss, Sebastian K. Müller, Thomas Rackow, Junhong Lee, Edgar Dolores-Tesillos, Imme Benedict, Matthias Aengenheyster, Razvan Aguridan, Gabriele Arduini, Alexander J. Baker, Jiawei Bao, Swantje Bastin, Eulàlia Baulenas, Tobias Becker, Sebastian Beyer, Hendryk Bockelmann, Nils Brüggemann, Lukas Brunner, Suvarchal K. Cheedela, Sushant Das, Jasper Denissen, Ian Dragaud, Piotr Dziekan, Madeleine Ekblom, Jan Frederik Engels, Monika Esch, Richard Forbes, Claudia Frauen, Lilli Freischem, Diego García-Maroto, Philipp Geier, Paul Gierz, Álvaro González-Cervera, Katherine Grayson, Matthew Griffith, Oliver Gutjahr, Helmuth Haak, Ioan Hadade, Kerstin Haslehner, Shabeh ul Hasson, Jan Hegewald, Lukas Kluft, Aleksei Koldunov, Nikolay Koldunov, Tobias Kölling, Shunya Koseki, Sergey Kosukhin, Josh Kousal, Peter Kuma, Arjun U. Kumar, Rumeng Li, Nicolas Maury, Maximilian Meindl, Sebastian Milinski, Kristian Mogensen, Bimochan Niraula, Jakub Nowak, Divya Sri Praturi, Ulrike Proske, Dian Putrasahan, René Redler, David Santuy, Domokos Sármány, Reiner Schnur, Patrick Scholz, Dmitry Sidorenko, Dorian Spät, Birgit Sützl, Daisuke Takasuka, Adrian Tompkins, Alejandro Uribe, Mirco Valentini, Menno Veerman, Aiko Voigt, Sarah Warnau, Fabian Wachsmann, Marta Wacławczyk, Nils Wedi, Karl-Hermann Wieners, Jonathan Wille, Marius Winkler, Yuting Wu, Florian Ziemen, Janos Zimmermann, Frida A.-M. Bender, Dragana Bojovic, Sandrine Bony, Simona Bordoni, Patrice Brehmer, Marcus Dengler, Emanuel Dutra, Saliou Faye, Erich Fischer, Chiel van Heerwaarden, Cathy Hohenegger, Heikki Järvinen, Markus Jochum, Thomas Jung, Johann H. Jungclaus, Noel S. Keenlyside, Daniel Klocke, Heike Konow, Martina Klose, Szymon Malinowski, Olivia Martius, Thorsten Mauritsen, Juan Pedro Mellado, Theresa Mieslinger, Elsa Mohino, Hanna Pawłowska, Karsten Peters-von Gehlen, Abdoulaye Sarré, Pajam Sobhani, Philip Stier, Lauri Tuppi, Pier Luigi Vidale, Irina Sandu, and Bjorn Stevens
Geosci. Model Dev., 18, 7735–7761, https://doi.org/10.5194/gmd-18-7735-2025, https://doi.org/10.5194/gmd-18-7735-2025, 2025
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The Next Generation of Earth Modeling Systems project (nextGEMS) developed two Earth system models that use horizontal grid spacing of 10 km and finer, giving more fidelity to the representation of local phenomena, globally. In its fourth cycle, nextGEMS simulated the Earth System climate over the 2020–2049 period under the SSP3-7.0 scenario. Here, we provide an overview of nextGEMS, insights into the model development, and the realism of multi-decadal, kilometer-scale simulations.
Robert G. Bingham, Julien A. Bodart, Marie G. P. Cavitte, Ailsa Chung, Rebecca J. Sanderson, Johannes C. R. Sutter, Olaf Eisen, Nanna B. Karlsson, Joseph A. MacGregor, Neil Ross, Duncan A. Young, David W. Ashmore, Andreas Born, Winnie Chu, Xiangbin Cui, Reinhard Drews, Steven Franke, Vikram Goel, John W. Goodge, A. Clara J. Henry, Antoine Hermant, Benjamin H. Hills, Nicholas Holschuh, Michelle R. Koutnik, Gwendolyn J.-M. C. Leysinger Vieli, Emma J. MacKie, Elisa Mantelli, Carlos Martín, Felix S. L. Ng, Falk M. Oraschewski, Felipe Napoleoni, Frédéric Parrenin, Sergey V. Popov, Therese Rieckh, Rebecca Schlegel, Dustin M. Schroeder, Martin J. Siegert, Xueyuan Tang, Thomas O. Teisberg, Kate Winter, Shuai Yan, Harry Davis, Christine F. Dow, Tyler J. Fudge, Tom A. Jordan, Bernd Kulessa, Kenichi Matsuoka, Clara J. Nyqvist, Maryam Rahnemoonfar, Matthew R. Siegfried, Shivangini Singh, Vjeran Višnjević, Rodrigo Zamora, and Alexandra Zuhr
The Cryosphere, 19, 4611–4655, https://doi.org/10.5194/tc-19-4611-2025, https://doi.org/10.5194/tc-19-4611-2025, 2025
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The ice sheets covering Antarctica have built up over millenia through successive snowfall events which become buried and preserved as internal surfaces of equal age detectable with ice-penetrating radar. This paper describes an international initiative working together on these archival data to build a comprehensive 3-D picture of how old the ice is everywhere across Antarctica and how this is being used to reconstruct past and to predict future ice and climate behaviour.
Ailsa Chung, Frédéric Parrenin, Robert Mulvaney, Luca Vittuari, Massimo Frezzotti, Antonio Zanutta, David A. Lilien, Marie G. P. Cavitte, and Olaf Eisen
The Cryosphere, 19, 4125–4140, https://doi.org/10.5194/tc-19-4125-2025, https://doi.org/10.5194/tc-19-4125-2025, 2025
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We applied an ice flow model to a flow line from the summit of Dome C to the Beyond EPICA ice core drill site on Little Dome C in Antarctica. Results show that the oldest ice at the drill site may be 1.12 Ma (at an age density of 20 kyr m-1) and originate from around 15 km upstream. We also discuss the nature of the 200–250 m thick basal layer which could be composed of stagnant ice, disturbed ice or even accreted ice (possibly containing debris).
Miguel Moreno, André Lamott, Sepp Kipfstuhl, Ilka Weikusat, María-Gema Llorens, Yannick Heiser, and Dorthe Dahl-Jensen
EGUsphere, https://doi.org/10.5194/egusphere-2025-3647, https://doi.org/10.5194/egusphere-2025-3647, 2025
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By scanning a Greenland ice core, we studied the changes in ice flow. We found that during past rapid climate changes, the size of ice grains and the amount of impurities were the main factors controlling how the ice deformed. We found that other deep, structural properties of the ice did not change in the cores studied, suggesting they were not the primary cause of the variations in flow.
Nicolas Stoll, Ilka Weikusat, Daniela Jansen, Paul Bons, Kyra Darányi, Julien Westhoff, María-Gema Llorens, David Wallis, Jan Eichler, Tomotaka Saruya, Tomoyuki Homma, Sune Olander Rasmussen, Giulia Sinnl, Anders Svensson, Martyn Drury, Frank Wilhelms, Sepp Kipfstuhl, Dorthe Dahl-Jensen, and Johanna Kerch
The Cryosphere, 19, 3805–3830, https://doi.org/10.5194/tc-19-3805-2025, https://doi.org/10.5194/tc-19-3805-2025, 2025
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A better understanding of ice flow requires more observational data. The EastGRIP core is the first ice core through an active ice stream. We discuss crystal orientation data determining the present deformation regimes. A comparison with other deep cores shows the unique properties of EastGRIP and shows that deep ice likely originates from the Eemian. We further show that the overall plug flow of NEGIS is characterised by many small-scale variations, which remain to be considered in ice flow models.
Angelika Humbert, Veit Helm, Ole Zeising, Niklas Neckel, Matthias H. Braun, Shfaqat Abbas Khan, Martin Rückamp, Holger Steeb, Julia Sohn, Matthias Bohnen, and Ralf Müller
The Cryosphere, 19, 3009–3032, https://doi.org/10.5194/tc-19-3009-2025, https://doi.org/10.5194/tc-19-3009-2025, 2025
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We study the evolution of a massive lake on the Greenland Ice Sheet using satellite and airborne data and some modelling. The lake is emptying rapidly. Water flows to the glacier's base through cracks and triangular-shaped moulins that remain visible over the years. Some of them become reactivated. We find features inside the glacier that stem from drainage events with a width of even 1 km. These features are persistent over the years, although they are changing in shape.
Ole Zeising, Tore Hattermann, Lars Kaleschke, Sophie Berger, Olaf Boebel, Reinhard Drews, M. Reza Ershadi, Tanja Fromm, Frank Pattyn, Daniel Steinhage, and Olaf Eisen
The Cryosphere, 19, 2837–2854, https://doi.org/10.5194/tc-19-2837-2025, https://doi.org/10.5194/tc-19-2837-2025, 2025
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Basal melting of ice shelves impacts the mass loss of the Antarctic Ice Sheet. This study focuses on the Ekström Ice Shelf in East Antarctica, using multiyear data from an autonomous radar system. Results show a surprising seasonal pattern of high melt rates in winter and spring. The seasonalities of sea-ice growth and ocean density indicate that, in winter, dense water enhances plume activity and melt rates. Understanding these dynamics is crucial for improving future mass balance projections.
Katrina Lutz, Ilaria Tabone, Angelika Humbert, and Matthias Braun
The Cryosphere, 19, 2601–2614, https://doi.org/10.5194/tc-19-2601-2025, https://doi.org/10.5194/tc-19-2601-2025, 2025
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Supraglacial lakes develop from meltwater collecting on the surface of glaciers. These lakes can drain rapidly, discharging meltwater to the glacier bed. In this study, we assess the spatial and temporal distribution of rapid drainages in Northeast Greenland using optical satellite images. After comparing rapid drainage occurrence with several environmental and geophysical parameters, little indication of the influencing conditions for a rapid drainage was found.
Ja-Yeon Moon, Jan Streffing, Sun-Seon Lee, Tido Semmler, Miguel Andrés-Martínez, Jiao Chen, Eun-Byeoul Cho, Jung-Eun Chu, Christian L. E. Franzke, Jan P. Gärtner, Rohit Ghosh, Jan Hegewald, Songyee Hong, Dae-Won Kim, Nikolay Koldunov, June-Yi Lee, Zihao Lin, Chao Liu, Svetlana N. Loza, Wonsun Park, Woncheol Roh, Dmitry V. Sein, Sahil Sharma, Dmitry Sidorenko, Jun-Hyeok Son, Malte F. Stuecker, Qiang Wang, Gyuseok Yi, Martina Zapponini, Thomas Jung, and Axel Timmermann
Earth Syst. Dynam., 16, 1103–1134, https://doi.org/10.5194/esd-16-1103-2025, https://doi.org/10.5194/esd-16-1103-2025, 2025
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Based on a series of storm-resolving greenhouse warming simulations conducted with the AWI-CM3 model at 9 km global atmosphere and 4–25 km ocean resolution, we present new projections of regional climate change, modes of climate variability, and extreme events. The 10-year-long high-resolution simulations for the 2000s, 2030s, 2060s, and 2090s were initialized from a coarser-resolution transient run (31 km atmosphere) which follows the SSP5-8.5 greenhouse gas emission scenario from 1950–2100 CE.
Hu Yang, Xiaoxu Shi, Xulong Wang, Qingsong Liu, Yi Zhong, Xiaodong Liu, Youbin Sun, Yanjun Cai, Fei Liu, Gerrit Lohmann, Martin Werner, Zhimin Jian, Tainã M. L. Pinho, Hai Cheng, Lijuan Lu, Jiping Liu, Chao-Yuan Yang, Qinghua Yang, Yongyun Hu, Xing Cheng, Jingyu Zhang, and Dake Chen
Clim. Past, 21, 1263–1279, https://doi.org/10.5194/cp-21-1263-2025, https://doi.org/10.5194/cp-21-1263-2025, 2025
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For 1 century, the hemispheric summer insolation is proposed as a key pacemaker of astronomical climate change. However, an increasing number of geologic records reveal that the low-latitude hydrological cycle shows asynchronous precessional evolutions that are very often out of phase with the summer insolation. Here, we propose that the astronomically driven low-latitude hydrological cycle is not paced by summer insolation but by shifting perihelion.
Lutz Schirrmeister, Margret C. Fuchs, Thomas Opel, Andrei Andreev, Frank Kienast, Andrea Schneider, Larisa Nazarova, Larisa Frolova, Svetlana Kuzmina, Tatiana Kuznetsova, Vladimir Tumskoy, Heidrun Matthes, Gerrit Lohmann, Guido Grosse, Viktor Kunitsky, Hanno Meyer, Heike H. Zimmermann, Ulrike Herzschuh, Thomas Böhmer, Stuart Umbo, Sevi Modestou, Sebastian F. M. Breitenbach, Anfisa Pismeniuk, Georg Schwamborn, Stephanie Kusch, and Sebastian Wetterich
Clim. Past, 21, 1143–1184, https://doi.org/10.5194/cp-21-1143-2025, https://doi.org/10.5194/cp-21-1143-2025, 2025
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Geochronological, cryolithological, paleoecological, and modeling data reconstruct the Last Interglacial (LIG) climate around the New Siberian Islands and reveal significantly warmer conditions compared to today. The critical challenges in predicting future ecosystem responses lie in the fact that the land–ocean distribution during the LIG was markedly different from today, affecting the degree of continentality, which played a major role in modulating climate and ecosystem dynamics.
Lea-Sophie Höyns, Thomas Kleiner, Andreas Rademacher, Martin Rückamp, Michael Wolovick, and Angelika Humbert
The Cryosphere, 19, 2133–2158, https://doi.org/10.5194/tc-19-2133-2025, https://doi.org/10.5194/tc-19-2133-2025, 2025
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The sliding of glaciers over bedrock is influenced by water pressure in the underlying hydrological system and the roughness of the land underneath the glacier. We estimate this roughness through a modeling approach that optimizes this unknown parameter. Additionally, we simulate water pressure, enhancing the reliability of the computed drag at the ice sheet base. The resulting data are provided to other modelers and scientists conducting geophysical field observations.
Hameed Moqadam and Olaf Eisen
The Cryosphere, 19, 2159–2196, https://doi.org/10.5194/tc-19-2159-2025, https://doi.org/10.5194/tc-19-2159-2025, 2025
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This is an overview of methodologies that have been applied to map the internal reflection horizons, or ice-layer boundaries, of ice sheets on Earth and other planets. We briefly explain radar applications in glaciology and the methods which have been used and published. There are summaries of the published work of the last 2 decades. Finally, we conclude by introducing the gaps and opportunities for further advancement in this field, and we present possible future directions.
Peter Köhler
Clim. Past, 21, 1043–1060, https://doi.org/10.5194/cp-21-1043-2025, https://doi.org/10.5194/cp-21-1043-2025, 2025
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Using a carbon cycle model, I show that the 405 kyr periodicity found in marine δ13C during the last 5 million years and the offset in atmospheric δ13CO2 between the Last Glacial Maximum and the Penultimate Glacial Maximum are probably related to each other. They can be explained by variations in the δ13C signature of weathered carbonate rock or of volcanically degassed CO2, which vary mainly with obliquity (41 kyr), suggesting that Northern Hemispheric land ice sheets are their ultimate drivers.
Daniel Müller, Bo Liu, Walter Geibert, Moritz Holtappels, Lasse Sander, Elda Miramontes, Heidi Taubner, Susann Henkel, Kai-Uwe Hinrichs, Denise Bethke, Ingrid Dohrmann, and Sabine Kasten
Biogeosciences, 22, 2541–2567, https://doi.org/10.5194/bg-22-2541-2025, https://doi.org/10.5194/bg-22-2541-2025, 2025
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Coastal and shelf sediments are the most important sinks for organic carbon (OC) on Earth. We produced a new high-resolution sediment and porewater data set from the Helgoland Mud Area (HMA), North Sea, to determine which depositional factors control the preservation of OC. The burial efficiency is highest in an area of high sedimentation and terrigenous OC. The HMA covers 0.09 % of the North Sea but accounts for 0.76 % of its OC accumulation, highlighting the importance of the depocentre.
Peter U. Clark, Jeremy D. Shakun, Yair Rosenthal, Chenyu Zhu, Patrick J. Bartlein, Jonathan M. Gregory, Peter Köhler, Zhengyu Liu, and Daniel P. Schrag
Clim. Past, 21, 973–1000, https://doi.org/10.5194/cp-21-973-2025, https://doi.org/10.5194/cp-21-973-2025, 2025
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We reconstruct changes in mean ocean temperature (ΔMOT) over the last 4.5 Myr. We find that the ratio of ΔMOT to changes in global mean sea surface temperature was around 0.5 before the Middle Pleistocene transition but was 1 thereafter. We subtract our ΔMOT reconstruction from the global δ18O record to derive the δ18O of seawater. Finally, we develop a theoretical understanding of why the ratio of ΔMOT / ΔGMSST changed over the Plio-Pleistocene.
Tamara Annina Gerber, David A. Lilien, Niels F. Nymand, Daniel Steinhage, Olaf Eisen, and Dorthe Dahl-Jensen
The Cryosphere, 19, 1955–1971, https://doi.org/10.5194/tc-19-1955-2025, https://doi.org/10.5194/tc-19-1955-2025, 2025
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This study examines how anisotropic scattering and birefringence affect radar signals in ice sheets. Using data from northeast Greenland, we show that anisotropic scattering – driven by subtle ice crystal orientation changes – dominates the azimuthal power response. We find a strong link between scattering strength, orientation, and stratigraphy. This suggests anisotropic scattering can reveal crystal fabric orientation and differentiate ice units from distinct climatic periods.
Laura Schild, Peter Ewald, Chenzhi Li, Raphaël Hébert, Thomas Laepple, and Ulrike Herzschuh
Earth Syst. Sci. Data, 17, 2007–2033, https://doi.org/10.5194/essd-17-2007-2025, https://doi.org/10.5194/essd-17-2007-2025, 2025
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This study reconstructed vegetation and tree cover in the Northern Hemisphere from a harmonized dataset of pollen counts from sediment and peat cores for the past 14 000 years. A model was applied to correct for differences in pollen production between different plants, and modern remote-sensing forest cover was used to validate the reconstructed tree cover. Accurate data on past vegetation are invaluable for the investigation of vegetation–climate dynamics and the validation of vegetation models.
Torsten Kanzow, Angelika Humbert, Thomas Mölg, Mirko Scheinert, Matthias Braun, Hans Burchard, Francesca Doglioni, Philipp Hochreuther, Martin Horwath, Oliver Huhn, Maria Kappelsberger, Jürgen Kusche, Erik Loebel, Katrina Lutz, Ben Marzeion, Rebecca McPherson, Mahdi Mohammadi-Aragh, Marco Möller, Carolyne Pickler, Markus Reinert, Monika Rhein, Martin Rückamp, Janin Schaffer, Muhammad Shafeeque, Sophie Stolzenberger, Ralph Timmermann, Jenny Turton, Claudia Wekerle, and Ole Zeising
The Cryosphere, 19, 1789–1824, https://doi.org/10.5194/tc-19-1789-2025, https://doi.org/10.5194/tc-19-1789-2025, 2025
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The Greenland Ice Sheet represents the second-largest contributor to global sea-level rise. We quantify atmosphere, ice and ocean processes related to the mass balance of glaciers in northeast Greenland, focusing on Greenland’s largest floating ice tongue, the 79° N Glacier. We find that together, the different in situ and remote sensing observations and model simulations reveal a consistent picture of a coupled atmosphere–ice sheet–ocean system that has entered a phase of major change.
Tsai-Wen Lin, Tommaso Tesi, Jens Hefter, Hendrik Grotheer, Jutta Wollenburg, Florian Adolphi, Henning A. Bauch, Alessio Nogarotto, Juliane Müller, and Gesine Mollenhauer
Clim. Past, 21, 753–772, https://doi.org/10.5194/cp-21-753-2025, https://doi.org/10.5194/cp-21-753-2025, 2025
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In order to understand the mechanisms governing permafrost organic matter remobilization, we investigated organic matter composition during past intervals of rapid sea-level rise, of inland warming, and of dense sea-ice cover in the Laptev Sea. We find that sea-level rise resulted in widespread erosion and transport of permafrost materials to the ocean but that erosion is mitigated by regional dense sea-ice cover. Factors like inland warming or floods increase permafrost mobilization locally.
Ole Pinner, Friederike Pollmann, Markus Janout, Gunnar Voet, and Torsten Kanzow
Ocean Sci., 21, 701–726, https://doi.org/10.5194/os-21-701-2025, https://doi.org/10.5194/os-21-701-2025, 2025
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The Weddell Sea Bottom Water gravity current transports dense water from the continental shelf to the deep sea and is crucial for the formation of new deep-sea water. Building on vertical profiles and time series measured in the northwestern Weddell Sea, we apply three methods to distinguish turbulence caused by internal waves from that by other sources. We find that in the upper part of the gravity current, internal waves are important for the mixing of less dense water down into the current.
Steven Franke, Daniel Steinhage, Veit Helm, Alexandra M. Zuhr, Julien A. Bodart, Olaf Eisen, and Paul Bons
The Cryosphere, 19, 1153–1180, https://doi.org/10.5194/tc-19-1153-2025, https://doi.org/10.5194/tc-19-1153-2025, 2025
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The study presents internal reflection horizons (IRHs) over an area of 450 000 km² from western Dronning Maud Land, Antarctica, spanning 4.8–91 ka. Using radar and ice core data, nine IRHs were dated and correlated with volcanic events. The data enhance our understanding of the ice sheet's age–depth architecture, accumulation, and dynamics. The findings inform ice flow models and contribute to Antarctic-wide comparisons of IRHs, supporting efforts toward a 3D age–depth ice sheet model.
Rémi Dallmayr, Hannah Meyer, Vasileios Gkinis, Thomas Laepple, Melanie Behrens, Frank Wilhelms, and Maria Hörhold
The Cryosphere, 19, 1067–1083, https://doi.org/10.5194/tc-19-1067-2025, https://doi.org/10.5194/tc-19-1067-2025, 2025
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Recent studies showed that a large number of independent vertical profiles allow for inferring a common local climate signal from the stacked stable water isotope record. Through investigating instrumental limitation and the effect of percolation of such porous samples, this study assesses the continuous flow analysis (CFA) technique in order to analyze the significant number of snow surface profiles within a reasonable time and with high quality.
Ying Ye, Guy Munhoven, Peter Köhler, Martin Butzin, Judith Hauck, Özgür Gürses, and Christoph Völker
Geosci. Model Dev., 18, 977–1000, https://doi.org/10.5194/gmd-18-977-2025, https://doi.org/10.5194/gmd-18-977-2025, 2025
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Many biogeochemistry models assume all material reaching the seafloor is remineralized and returned to solution, which is sufficient for studies on short-term climate change. Under long-term climate change, the carbon storage in sediments slows down carbon cycling and influences feedbacks in the atmosphere–ocean–sediment system. This paper describes the coupling of a sediment model to an ocean biogeochemistry model and presents results under the pre-industrial climate and under CO2 perturbation.
Christoph Dahle, Eva Boergens, Ingo Sasgen, Thorben Döhne, Sven Reißland, Henryk Dobslaw, Volker Klemann, Michael Murböck, Rolf König, Robert Dill, Mike Sips, Ulrike Sylla, Andreas Groh, Martin Horwath, and Frank Flechtner
Earth Syst. Sci. Data, 17, 611–631, https://doi.org/10.5194/essd-17-611-2025, https://doi.org/10.5194/essd-17-611-2025, 2025
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GRACE and GRACE-FO are unique observing systems to quantify mass changes at the Earth’s surface from space. Time series of these mass changes are of high value for various applications, e.g., in hydrology, glaciology, and oceanography. GravIS (Gravity Information Service) provides easy access to user-friendly, regularly updated mass anomaly products. The portal visualizes and describes these data, aiming to highlight their significance for understanding changes in the climate system.
Tatiana Klimiuk, Patrick Ludwig, Antonio Sanchez-Benitez, Helge F. Goessling, Peter Braesicke, and Joaquim G. Pinto
Earth Syst. Dynam., 16, 239–255, https://doi.org/10.5194/esd-16-239-2025, https://doi.org/10.5194/esd-16-239-2025, 2025
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Our study examines potential changes in heatwaves in central Europe due to global warming, using the 2019 summer heatwave as an example. By producing high-resolution storylines, we provide insights into how future heatwaves might spread, how they might persist for longer, and where stronger or weaker temperature increases may occur. This research helps us understand regional thermodynamic responses and highlights the importance of local strategies to protect communities from future heat events.
Wee Wei Khoo, Juliane Müller, Oliver Esper, Wenshen Xiao, Christian Stepanek, Paul Gierz, Gerrit Lohmann, Walter Geibert, Jens Hefter, and Gesine Mollenhauer
Clim. Past, 21, 299–326, https://doi.org/10.5194/cp-21-299-2025, https://doi.org/10.5194/cp-21-299-2025, 2025
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Using a multiproxy approach, we analyzed biomarkers and diatom assemblages from a marine sediment core from the Powell Basin, Weddell Sea. The results reveal the first continuous coastal Antarctic sea ice record since the Last Penultimate Glacial. Our findings contribute valuable insights into past glacial–interglacial sea ice responses to a changing climate and enhance our understanding of ocean–sea ice–ice shelf interactions and dynamics.
Thomas Rackow, Xabier Pedruzo-Bagazgoitia, Tobias Becker, Sebastian Milinski, Irina Sandu, Razvan Aguridan, Peter Bechtold, Sebastian Beyer, Jean Bidlot, Souhail Boussetta, Willem Deconinck, Michail Diamantakis, Peter Dueben, Emanuel Dutra, Richard Forbes, Rohit Ghosh, Helge F. Goessling, Ioan Hadade, Jan Hegewald, Thomas Jung, Sarah Keeley, Lukas Kluft, Nikolay Koldunov, Aleksei Koldunov, Tobias Kölling, Josh Kousal, Christian Kühnlein, Pedro Maciel, Kristian Mogensen, Tiago Quintino, Inna Polichtchouk, Balthasar Reuter, Domokos Sármány, Patrick Scholz, Dmitry Sidorenko, Jan Streffing, Birgit Sützl, Daisuke Takasuka, Steffen Tietsche, Mirco Valentini, Benoît Vannière, Nils Wedi, Lorenzo Zampieri, and Florian Ziemen
Geosci. Model Dev., 18, 33–69, https://doi.org/10.5194/gmd-18-33-2025, https://doi.org/10.5194/gmd-18-33-2025, 2025
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Detailed global climate model simulations have been created based on a numerical weather prediction model, offering more accurate spatial detail down to the scale of individual cities ("kilometre-scale") and a better understanding of climate phenomena such as atmospheric storms, whirls in the ocean, and cracks in sea ice. The new model aims to provide globally consistent information on local climate change with greater precision, benefiting environmental planning and local impact modelling.
Viorica Nagavciuc, Gerhard Helle, Maria Rădoane, Cătălin-Constantin Roibu, Mihai-Gabriel Cotos, and Monica Ionita
Biogeosciences, 22, 55–69, https://doi.org/10.5194/bg-22-55-2025, https://doi.org/10.5194/bg-22-55-2025, 2025
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We reconstructed drought conditions for the past 200 years for central and eastern parts of Europe (Romania) using δ18O in oak tree ring cellulose from Romania, revealing periods of both extreme wetness (e.g., 1905–1915) and dryness (e.g., 1818–1835). The most severe droughts occurred in the 19th and 21st centuries, likely linked to large-scale atmospheric circulation. This research highlights the potential of tree rings to improve our understanding of long-term climate variability in Europe.
Bennet Juhls, Anne Morgenstern, Jens Hölemann, Antje Eulenburg, Birgit Heim, Frederieke Miesner, Hendrik Grotheer, Gesine Mollenhauer, Hanno Meyer, Ephraim Erkens, Felica Yara Gehde, Sofia Antonova, Sergey Chalov, Maria Tereshina, Oxana Erina, Evgeniya Fingert, Ekaterina Abramova, Tina Sanders, Liudmila Lebedeva, Nikolai Torgovkin, Georgii Maksimov, Vasily Povazhnyi, Rafael Gonçalves-Araujo, Urban Wünsch, Antonina Chetverova, Sophie Opfergelt, and Pier Paul Overduin
Earth Syst. Sci. Data, 17, 1–28, https://doi.org/10.5194/essd-17-1-2025, https://doi.org/10.5194/essd-17-1-2025, 2025
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The Siberian Arctic is warming fast: permafrost is thawing, river chemistry is changing, and coastal ecosystems are affected. We aimed to understand changes in the Lena River, a major Arctic river flowing to the Arctic Ocean, by collecting 4.5 years of detailed water data, including temperature and carbon and nutrient contents. This dataset records current conditions and helps us to detect future changes. Explore it at https://doi.org/10.1594/PANGAEA.913197 and https://lena-monitoring.awi.de/.
Monica Ionita, Petru Vaideanu, Bogdan Antonescu, Catalin Roibu, Qiyun Ma, and Viorica Nagavciuc
Nat. Hazards Earth Syst. Sci., 24, 4683–4706, https://doi.org/10.5194/nhess-24-4683-2024, https://doi.org/10.5194/nhess-24-4683-2024, 2024
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Eastern Europe's heat wave history is explored from 1885 to 2023, with a focus on pre-1960 events. The study reveals two periods with more frequent and intense heat waves (HWs): 1920s–1960s and 1980s–present. The research highlights the importance of a long-term perspective, revealing that extreme heat events have occurred throughout the entire study period, and it emphasizes the combined influence of climate change and natural variations on increasing HW severity.
Rui Xu, Chaofang Zhao, Stefanie Arndt, and Christian Haas
The Cryosphere, 18, 5769–5788, https://doi.org/10.5194/tc-18-5769-2024, https://doi.org/10.5194/tc-18-5769-2024, 2024
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The onset of snowmelt on Antarctic sea ice is an important indicator of sea ice change. In this study, we used two radar scatterometers to detect the onset of snowmelt on perennial Antarctic sea ice. Results show that since 2007, snowmelt onset has demonstrated strong interannual and regional variabilities. We also found that the difference in snowmelt onsets between the two scatterometers is closely related to snow metamorphism.
Arnaud Nicolas, Gesine Mollenhauer, Johannes Lachner, Konstanze Stübner, Maylin Malter, Jutta Wollenburg, Hendrik Grotheer, and Florian Adolphi
Clim. Past, 20, 2617–2628, https://doi.org/10.5194/cp-20-2617-2024, https://doi.org/10.5194/cp-20-2617-2024, 2024
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We use the authigenic 10Be/9Be record of a Laptev Sea sediment core for the period 8–14 kyr BP and synchronize it with the 10Be records from absolutely dated ice cores. We employed a likelihood function to calculate the ΔR values. A benthic ΔR value of +345±60 14C years was estimated, which corresponds to a marine reservoir age of 848±90 14C years. This new ΔR value was used to refine the age–depth model for core PS2458-4, establishing it as a potential reference chronology for the Laptev Sea.
Katrina Lutz, Lily Bever, Christian Sommer, Thorsten Seehaus, Angelika Humbert, Mirko Scheinert, and Matthias Braun
The Cryosphere, 18, 5431–5449, https://doi.org/10.5194/tc-18-5431-2024, https://doi.org/10.5194/tc-18-5431-2024, 2024
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The estimation of the amount of water found within supraglacial lakes is important for understanding how much water is lost from glaciers each year. Here, we develop two new methods for estimating supraglacial lake volume that can be easily applied on a large scale. Furthermore, we compare these methods to two previously developed methods in order to determine when it is best to use each method. Finally, three of these methods are applied to peak melt dates over an area in Northeast Greenland.
Emma Pearce, Dimitri Zigone, Coen Hofstede, Andreas Fichtner, Joachim Rimpot, Sune Olander Rasmussen, Johannes Freitag, and Olaf Eisen
The Cryosphere, 18, 4917–4932, https://doi.org/10.5194/tc-18-4917-2024, https://doi.org/10.5194/tc-18-4917-2024, 2024
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Our study near EastGRIP camp in Greenland shows varying firn properties by direction (crucial for studying ice stream stability, structure, surface mass balance, and past climate conditions). We used dispersion curve analysis of Love and Rayleigh waves to show firn is nonuniform along and across the flow of an ice stream due to wind patterns, seasonal variability, and the proximity to the edge of the ice stream. This method better informs firn structure, advancing ice stream understanding.
Colin G. Jones, Fanny Adloff, Ben B. B. Booth, Peter M. Cox, Veronika Eyring, Pierre Friedlingstein, Katja Frieler, Helene T. Hewitt, Hazel A. Jeffery, Sylvie Joussaume, Torben Koenigk, Bryan N. Lawrence, Eleanor O'Rourke, Malcolm J. Roberts, Benjamin M. Sanderson, Roland Séférian, Samuel Somot, Pier Luigi Vidale, Detlef van Vuuren, Mario Acosta, Mats Bentsen, Raffaele Bernardello, Richard Betts, Ed Blockley, Julien Boé, Tom Bracegirdle, Pascale Braconnot, Victor Brovkin, Carlo Buontempo, Francisco Doblas-Reyes, Markus Donat, Italo Epicoco, Pete Falloon, Sandro Fiore, Thomas Frölicher, Neven S. Fučkar, Matthew J. Gidden, Helge F. Goessling, Rune Grand Graversen, Silvio Gualdi, José M. Gutiérrez, Tatiana Ilyina, Daniela Jacob, Chris D. Jones, Martin Juckes, Elizabeth Kendon, Erik Kjellström, Reto Knutti, Jason Lowe, Matthew Mizielinski, Paola Nassisi, Michael Obersteiner, Pierre Regnier, Romain Roehrig, David Salas y Mélia, Carl-Friedrich Schleussner, Michael Schulz, Enrico Scoccimarro, Laurent Terray, Hannes Thiemann, Richard A. Wood, Shuting Yang, and Sönke Zaehle
Earth Syst. Dynam., 15, 1319–1351, https://doi.org/10.5194/esd-15-1319-2024, https://doi.org/10.5194/esd-15-1319-2024, 2024
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We propose a number of priority areas for the international climate research community to address over the coming decade. Advances in these areas will both increase our understanding of past and future Earth system change, including the societal and environmental impacts of this change, and deliver significantly improved scientific support to international climate policy, such as future IPCC assessments and the UNFCCC Global Stocktake.
Anne F. Van Loon, Sarra Kchouk, Alessia Matanó, Faranak Tootoonchi, Camila Alvarez-Garreton, Khalid E. A. Hassaballah, Minchao Wu, Marthe L. K. Wens, Anastasiya Shyrokaya, Elena Ridolfi, Riccardo Biella, Viorica Nagavciuc, Marlies H. Barendrecht, Ana Bastos, Louise Cavalcante, Franciska T. de Vries, Margaret Garcia, Johanna Mård, Ileen N. Streefkerk, Claudia Teutschbein, Roshanak Tootoonchi, Ruben Weesie, Valentin Aich, Juan P. Boisier, Giuliano Di Baldassarre, Yiheng Du, Mauricio Galleguillos, René Garreaud, Monica Ionita, Sina Khatami, Johanna K. L. Koehler, Charles H. Luce, Shreedhar Maskey, Heidi D. Mendoza, Moses N. Mwangi, Ilias G. Pechlivanidis, Germano G. Ribeiro Neto, Tirthankar Roy, Robert Stefanski, Patricia Trambauer, Elizabeth A. Koebele, Giulia Vico, and Micha Werner
Nat. Hazards Earth Syst. Sci., 24, 3173–3205, https://doi.org/10.5194/nhess-24-3173-2024, https://doi.org/10.5194/nhess-24-3173-2024, 2024
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Drought is a creeping phenomenon but is often still analysed and managed like an isolated event, without taking into account what happened before and after. Here, we review the literature and analyse five cases to discuss how droughts and their impacts develop over time. We find that the responses of hydrological, ecological, and social systems can be classified into four types and that the systems interact. We provide suggestions for further research and monitoring, modelling, and management.
Julien Westhoff, Johannes Freitag, Anaïs Orsi, Patricia Martinerie, Ilka Weikusat, Michael Dyonisius, Xavier Faïn, Kevin Fourteau, and Thomas Blunier
The Cryosphere, 18, 4379–4397, https://doi.org/10.5194/tc-18-4379-2024, https://doi.org/10.5194/tc-18-4379-2024, 2024
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We study the EastGRIP area, Greenland, in detail with traditional and novel techniques. Due to the compaction of the ice, at a certain depth, atmospheric gases can no longer exchange, and the atmosphere is trapped in air bubbles in the ice. We find this depth by pumping air from a borehole, modeling, and using a new technique based on the optical appearance of the ice. Our results suggest that the close-off depth lies at around 58–61 m depth and more precisely at 58.3 m depth.
Yi Zhou, Xianwei Wang, Ruibo Lei, Arttu Jutila, Donald K. Perovich, Luisa von Albedyll, Dmitry V. Divine, Yu Zhang, and Christian Haas
EGUsphere, https://doi.org/10.5194/egusphere-2024-2821, https://doi.org/10.5194/egusphere-2024-2821, 2024
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This study examines how the bulk density of Arctic sea ice varies seasonally, a factor often overlooked in satellite measurements of sea ice thickness. From October to April, we found significant seasonal variations in sea ice bulk density at different spatial scales using direct observations as well as airborne and satellite data. New models were then developed to indirectly predict sea ice bulk density. This advance can improve our ability to monitor changes in Arctic sea ice.
Yugeng Chen, Pengyang Song, Xianyao Chen, and Gerrit Lohmann
Clim. Past, 20, 2001–2015, https://doi.org/10.5194/cp-20-2001-2024, https://doi.org/10.5194/cp-20-2001-2024, 2024
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Our study examines the Atlantic Meridional Overturning Circulation (AMOC) during the Last Glacial Maximum (LGM), a period with higher tidal dissipation. Despite increased tidal mixing, our model simulations show that the AMOC remained relatively shallow, consistent with paleoproxy data and resolving previous inconsistencies between proxy data and model simulations. This research highlights the importance of strong ocean stratification during the LGM and its interaction with tidal mixing.
Veit Helm, Alireza Dehghanpour, Ronny Hänsch, Erik Loebel, Martin Horwath, and Angelika Humbert
The Cryosphere, 18, 3933–3970, https://doi.org/10.5194/tc-18-3933-2024, https://doi.org/10.5194/tc-18-3933-2024, 2024
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We present a new approach (AWI-ICENet1), based on a deep convolutional neural network, for analysing satellite radar altimeter measurements to accurately determine the surface height of ice sheets. Surface height estimates obtained with AWI-ICENet1 (along with related products, such as ice sheet height change and volume change) show improved and unbiased results compared to other products. This is important for the long-term monitoring of ice sheet mass loss and its impact on sea level rise.
Falk M. Oraschewski, Inka Koch, M. Reza Ershadi, Jonathan D. Hawkins, Olaf Eisen, and Reinhard Drews
The Cryosphere, 18, 3875–3889, https://doi.org/10.5194/tc-18-3875-2024, https://doi.org/10.5194/tc-18-3875-2024, 2024
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Mountain glaciers have a layered structure which contains information about past snow accumulation and ice flow. Using ground-penetrating radar instruments, the internal structure can be observed. The detection of layers in the deeper parts of a glacier is often difficult. Here, we present a new approach for imaging the englacial structure of an Alpine glacier (Colle Gnifetti, Switzerland and Italy) using a phase-sensitive radar that can detect reflection depth changes at sub-wavelength scales.
Fyntan Shaw, Andrew M. Dolman, Torben Kunz, Vasileios Gkinis, and Thomas Laepple
The Cryosphere, 18, 3685–3698, https://doi.org/10.5194/tc-18-3685-2024, https://doi.org/10.5194/tc-18-3685-2024, 2024
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Fast variability of water isotopes in ice cores is attenuated by diffusion but can be restored if the diffusion length is accurately estimated. Current estimation methods are inadequate for deep ice, mischaracterising millennial-scale climate variability. We address this using variability estimates from shallower ice. The estimated diffusion length of 31 cm for the bottom of the Dome C ice core is 20 cm less than the old method, enabling signal recovery on timescales previously considered lost.
Erik Loebel, Mirko Scheinert, Martin Horwath, Angelika Humbert, Julia Sohn, Konrad Heidler, Charlotte Liebezeit, and Xiao Xiang Zhu
The Cryosphere, 18, 3315–3332, https://doi.org/10.5194/tc-18-3315-2024, https://doi.org/10.5194/tc-18-3315-2024, 2024
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Comprehensive datasets of calving-front changes are essential for studying and modeling outlet glaciers. Current records are limited in temporal resolution due to manual delineation. We use deep learning to automatically delineate calving fronts for 23 glaciers in Greenland. Resulting time series resolve long-term, seasonal, and subseasonal patterns. We discuss the implications of our results and provide the cryosphere community with a data product and an implementation of our processing system.
Gemma M. Brett, Greg H. Leonard, Wolfgang Rack, Christian Haas, Patricia J. Langhorne, Natalie J. Robinson, and Anne Irvin
The Cryosphere, 18, 3049–3066, https://doi.org/10.5194/tc-18-3049-2024, https://doi.org/10.5194/tc-18-3049-2024, 2024
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Glacial meltwater with ice crystals flows from beneath ice shelves, causing thicker sea ice with sub-ice platelet layers (SIPLs) beneath. Thicker sea ice and SIPL reveal where and how much meltwater is outflowing. We collected continuous measurements of sea ice and SIPL. In winter, we observed rapid SIPL growth with strong winds. In spring, SIPLs grew when tides caused offshore circulation. Wind-driven and tidal circulation influence glacial meltwater outflow from ice shelf cavities.
Niels Fuchs, Luisa von Albedyll, Gerit Birnbaum, Felix Linhardt, Natascha Oppelt, and Christian Haas
The Cryosphere, 18, 2991–3015, https://doi.org/10.5194/tc-18-2991-2024, https://doi.org/10.5194/tc-18-2991-2024, 2024
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Melt ponds are key components of the Arctic sea ice system, yet methods to derive comprehensive pond depth data are missing. We present a shallow-water bathymetry retrieval to derive this elementary pond property at high spatial resolution from aerial images. The retrieval method is presented in a user-friendly way to facilitate replication. Furthermore, we provide pond properties on the MOSAiC expedition floe, giving insights into the three-dimensional pond evolution before and after drainage.
Niko Schmidt, Angelika Humbert, and Thomas Slawig
Geosci. Model Dev., 17, 4943–4959, https://doi.org/10.5194/gmd-17-4943-2024, https://doi.org/10.5194/gmd-17-4943-2024, 2024
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Future sea-level rise is of big significance for coastal regions. The melting and acceleration of glaciers plays a major role in sea-level change. Computer simulation of glaciers costs a lot of computational resources. In this publication, we test a new way of simulating glaciers. This approach produces the same results but has the advantage that it needs much less computation time. As simulations can be obtained with fewer computation resources, higher resolution and physics become affordable.
Yi Zhou, Xianwei Wang, Ruibo Lei, Luisa von Albedyll, Donald K. Perovich, Yu Zhang, and Christian Haas
EGUsphere, https://doi.org/10.5194/egusphere-2024-1240, https://doi.org/10.5194/egusphere-2024-1240, 2024
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This study examines how the density of Arctic sea ice varies seasonally, a factor often overlooked in satellite measurements of sea ice thickness. From October to April, using direct observations and satellite data, we found that sea ice density decreases significantly until mid-January due to increased porosity as the ice ages, and then stabilizes until April. We then developed new models to estimate sea ice density. This advance can improve our ability to monitor changes in Arctic sea ice.
Karl Kortum, Suman Singha, Gunnar Spreen, Nils Hutter, Arttu Jutila, and Christian Haas
The Cryosphere, 18, 2207–2222, https://doi.org/10.5194/tc-18-2207-2024, https://doi.org/10.5194/tc-18-2207-2024, 2024
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A dataset of 20 radar satellite acquisitions and near-simultaneous helicopter-based surveys of the ice topography during the MOSAiC expedition is constructed and used to train a variety of deep learning algorithms. The results give realistic insights into the accuracy of retrieval of measured ice classes using modern deep learning models. The models able to learn from the spatial distribution of the measured sea ice classes are shown to have a clear advantage over those that cannot.
Bjorn Stevens, Stefan Adami, Tariq Ali, Hartwig Anzt, Zafer Aslan, Sabine Attinger, Jaana Bäck, Johanna Baehr, Peter Bauer, Natacha Bernier, Bob Bishop, Hendryk Bockelmann, Sandrine Bony, Guy Brasseur, David N. Bresch, Sean Breyer, Gilbert Brunet, Pier Luigi Buttigieg, Junji Cao, Christelle Castet, Yafang Cheng, Ayantika Dey Choudhury, Deborah Coen, Susanne Crewell, Atish Dabholkar, Qing Dai, Francisco Doblas-Reyes, Dale Durran, Ayoub El Gaidi, Charlie Ewen, Eleftheria Exarchou, Veronika Eyring, Florencia Falkinhoff, David Farrell, Piers M. Forster, Ariane Frassoni, Claudia Frauen, Oliver Fuhrer, Shahzad Gani, Edwin Gerber, Debra Goldfarb, Jens Grieger, Nicolas Gruber, Wilco Hazeleger, Rolf Herken, Chris Hewitt, Torsten Hoefler, Huang-Hsiung Hsu, Daniela Jacob, Alexandra Jahn, Christian Jakob, Thomas Jung, Christopher Kadow, In-Sik Kang, Sarah Kang, Karthik Kashinath, Katharina Kleinen-von Königslöw, Daniel Klocke, Uta Kloenne, Milan Klöwer, Chihiro Kodama, Stefan Kollet, Tobias Kölling, Jenni Kontkanen, Steve Kopp, Michal Koran, Markku Kulmala, Hanna Lappalainen, Fakhria Latifi, Bryan Lawrence, June Yi Lee, Quentin Lejeun, Christian Lessig, Chao Li, Thomas Lippert, Jürg Luterbacher, Pekka Manninen, Jochem Marotzke, Satoshi Matsouoka, Charlotte Merchant, Peter Messmer, Gero Michel, Kristel Michielsen, Tomoki Miyakawa, Jens Müller, Ramsha Munir, Sandeep Narayanasetti, Ousmane Ndiaye, Carlos Nobre, Achim Oberg, Riko Oki, Tuba Özkan-Haller, Tim Palmer, Stan Posey, Andreas Prein, Odessa Primus, Mike Pritchard, Julie Pullen, Dian Putrasahan, Johannes Quaas, Krishnan Raghavan, Venkatachalam Ramaswamy, Markus Rapp, Florian Rauser, Markus Reichstein, Aromar Revi, Sonakshi Saluja, Masaki Satoh, Vera Schemann, Sebastian Schemm, Christina Schnadt Poberaj, Thomas Schulthess, Cath Senior, Jagadish Shukla, Manmeet Singh, Julia Slingo, Adam Sobel, Silvina Solman, Jenna Spitzer, Philip Stier, Thomas Stocker, Sarah Strock, Hang Su, Petteri Taalas, John Taylor, Susann Tegtmeier, Georg Teutsch, Adrian Tompkins, Uwe Ulbrich, Pier-Luigi Vidale, Chien-Ming Wu, Hao Xu, Najibullah Zaki, Laure Zanna, Tianjun Zhou, and Florian Ziemen
Earth Syst. Sci. Data, 16, 2113–2122, https://doi.org/10.5194/essd-16-2113-2024, https://doi.org/10.5194/essd-16-2113-2024, 2024
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To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change.
Lars Ackermann, Thomas Rackow, Kai Himstedt, Paul Gierz, Gregor Knorr, and Gerrit Lohmann
Geosci. Model Dev., 17, 3279–3301, https://doi.org/10.5194/gmd-17-3279-2024, https://doi.org/10.5194/gmd-17-3279-2024, 2024
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We present long-term simulations with interactive icebergs in the Southern Ocean. By melting, icebergs reduce the temperature and salinity of the surrounding ocean. In our simulations, we find that this cooling effect of iceberg melting is not limited to the surface ocean but also reaches the deep ocean and propagates northward into all ocean basins. Additionally, the formation of deep-water masses in the Southern Ocean is enhanced.
Peter Köhler and Stefan Mulitza
Clim. Past, 20, 991–1015, https://doi.org/10.5194/cp-20-991-2024, https://doi.org/10.5194/cp-20-991-2024, 2024
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We constructed 160 kyr long mono-specific stacks of δ13C and of δ18O from the wider tropics from the planktic foraminifera G. ruber and/or T. sacculifer and compared them with carbon cycle simulations using the BICYCLE-SE model. In our stacks and our model-based interpretation, we cannot detect a species-specific isotopic fractionation during hard-shell formation as a function of carbonate chemistry in the surrounding seawater, something which is called a carbonate ion effect.
Jennifer L. Middleton, Julia Gottschalk, Gisela Winckler, Jean Hanley, Carol Knudson, Jesse R. Farmer, Frank Lamy, Lorraine E. Lisiecki, and Expedition 383 Scientists
Geochronology, 6, 125–145, https://doi.org/10.5194/gchron-6-125-2024, https://doi.org/10.5194/gchron-6-125-2024, 2024
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We present oxygen isotope data for a new sediment core from the South Pacific and assign ages to our record by aligning distinct patterns in observed oxygen isotope changes to independently dated target records with the same patterns. We examine the age uncertainties associated with this approach caused by human vs. automated alignment and the sensitivity of outcomes to the choice of alignment target. These efforts help us understand the timing of past climate changes.
Alexandra M. Zuhr, Sonja Wahl, Hans Christian Steen-Larsen, Maria Hörhold, Hanno Meyer, Vasileios Gkinis, and Thomas Laepple
Earth Syst. Sci. Data, 16, 1861–1874, https://doi.org/10.5194/essd-16-1861-2024, https://doi.org/10.5194/essd-16-1861-2024, 2024
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We present stable water isotope data from the accumulation zone of the Greenland ice sheet. A spatial sampling scheme covering 39 m and three depth layers was carried out between 14 May and 3 August 2018. The data suggest spatial and temporal variability related to meteorological conditions, such as wind-driven snow redistribution and vapour–snow exchange processes. The data can be used to study the formation of the stable water isotopes signal, which is seen as a climate proxy.
Ole Zeising, Niklas Neckel, Nils Dörr, Veit Helm, Daniel Steinhage, Ralph Timmermann, and Angelika Humbert
The Cryosphere, 18, 1333–1357, https://doi.org/10.5194/tc-18-1333-2024, https://doi.org/10.5194/tc-18-1333-2024, 2024
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The 79° North Glacier in Greenland has experienced significant changes over the last decades. Due to extreme melt rates, the ice has thinned significantly in the vicinity of the grounding line, where a large subglacial channel has formed since 2010. We attribute these changes to warm ocean currents and increased subglacial discharge from surface melt. However, basal melting has decreased since 2018, indicating colder water inflow into the cavity below the glacier.
Luisa von Albedyll, Stefan Hendricks, Nils Hutter, Dmitrii Murashkin, Lars Kaleschke, Sascha Willmes, Linda Thielke, Xiangshan Tian-Kunze, Gunnar Spreen, and Christian Haas
The Cryosphere, 18, 1259–1285, https://doi.org/10.5194/tc-18-1259-2024, https://doi.org/10.5194/tc-18-1259-2024, 2024
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Leads (openings in sea ice cover) are created by sea ice dynamics. Because they are important for many processes in the Arctic winter climate, we aim to detect them with satellites. We present two new techniques to detect lead widths of a few hundred meters at high spatial resolution (700 m) and independent of clouds or sun illumination. We use the MOSAiC drift 2019–2020 in the Arctic for our case study and compare our new products to other existing lead products.
Viorica Nagavciuc, Simon L. L. Michel, Daniel F. Balting, Gerhard Helle, Mandy Freund, Gerhard H. Schleser, David N. Steger, Gerrit Lohmann, and Monica Ionita
Clim. Past, 20, 573–595, https://doi.org/10.5194/cp-20-573-2024, https://doi.org/10.5194/cp-20-573-2024, 2024
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The main aim of this paper is to present the summer vapor pressure deficit (VPD) reconstruction dataset for the last 400 years over Europe based on δ18O records by using a random forest approach. We provide both a spatial and a temporal long-term perspective on the past summer VPD and new insights into the relationship between summer VPD and large-scale atmospheric circulation. This is the first gridded reconstruction of the European summer VPD over the past 400 years.
Vera Dorothee Meyer, Jürgen Pätzold, Gesine Mollenhauer, Isla S. Castañeda, Stefan Schouten, and Enno Schefuß
Clim. Past, 20, 523–546, https://doi.org/10.5194/cp-20-523-2024, https://doi.org/10.5194/cp-20-523-2024, 2024
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The climatic factors sustaining vegetation in the Sahara during the African humid period (AHP) are still not fully understood. Using biomarkers in a marine sediment core from the eastern Mediterranean, we infer variations in Mediterranean (winter) and monsoonal (summer) rainfall in the Nile river watershed around the AHP. We find that winter and summer rain enhanced during the AHP, suggesting that Mediterranean moisture supported the monsoon in sustaining the “green Sahara”.
Martin Butzin, Ying Ye, Christoph Völker, Özgür Gürses, Judith Hauck, and Peter Köhler
Geosci. Model Dev., 17, 1709–1727, https://doi.org/10.5194/gmd-17-1709-2024, https://doi.org/10.5194/gmd-17-1709-2024, 2024
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In this paper we describe the implementation of the carbon isotopes 13C and 14C into the marine biogeochemistry model FESOM2.1-REcoM3 and present results of long-term test simulations. Our model results are largely consistent with marine carbon isotope reconstructions for the pre-anthropogenic period, but also exhibit some discrepancies.
Nathan Beech, Thomas Rackow, Tido Semmler, and Thomas Jung
Geosci. Model Dev., 17, 529–543, https://doi.org/10.5194/gmd-17-529-2024, https://doi.org/10.5194/gmd-17-529-2024, 2024
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Cost-reducing modeling strategies are applied to high-resolution simulations of the Southern Ocean in a changing climate. They are evaluated with respect to observations and traditional, lower-resolution modeling methods. The simulations effectively reproduce small-scale ocean flows seen in satellite data and are largely consistent with traditional model simulations after 4 °C of warming. Small-scale flows are found to intensify near bathymetric features and to become more variable.
Eduardo Queiroz Alves, Wanyee Wong, Jens Hefter, Hendrik Grotheer, Tommaso Tesi, Torben Gentz, Karin Zonneveld, and Gesine Mollenhauer
Clim. Past, 20, 121–136, https://doi.org/10.5194/cp-20-121-2024, https://doi.org/10.5194/cp-20-121-2024, 2024
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Our study reveals a previously unknown peat source for the massive influx of terrestrial organic matter that was exported from the European continent to the ocean during the last deglaciation. Our findings shed light on ancient terrestrial organic carbon mobilization, providing insights that are crucial for refining climate models.
Lukrecia Stulic, Ralph Timmermann, Stephan Paul, Rolf Zentek, Günther Heinemann, and Torsten Kanzow
Ocean Sci., 19, 1791–1808, https://doi.org/10.5194/os-19-1791-2023, https://doi.org/10.5194/os-19-1791-2023, 2023
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In the southern Weddell Sea, the strong sea ice growth in coastal polynyas drives formation of dense shelf water. By using a sea ice–ice shelf–ocean model with representation of the changing icescape based on satellite data, we find that polynya sea ice growth depends on both the regional atmospheric forcing and the icescape. Not just strength but also location of the sea ice growth in polynyas affects properties of the dense shelf water and the basal melting of the Filchner–Ronne Ice Shelf.
Hélène Seroussi, Vincent Verjans, Sophie Nowicki, Antony J. Payne, Heiko Goelzer, William H. Lipscomb, Ayako Abe-Ouchi, Cécile Agosta, Torsten Albrecht, Xylar Asay-Davis, Alice Barthel, Reinhard Calov, Richard Cullather, Christophe Dumas, Benjamin K. Galton-Fenzi, Rupert Gladstone, Nicholas R. Golledge, Jonathan M. Gregory, Ralf Greve, Tore Hattermann, Matthew J. Hoffman, Angelika Humbert, Philippe Huybrechts, Nicolas C. Jourdain, Thomas Kleiner, Eric Larour, Gunter R. Leguy, Daniel P. Lowry, Chistopher M. Little, Mathieu Morlighem, Frank Pattyn, Tyler Pelle, Stephen F. Price, Aurélien Quiquet, Ronja Reese, Nicole-Jeanne Schlegel, Andrew Shepherd, Erika Simon, Robin S. Smith, Fiammetta Straneo, Sainan Sun, Luke D. Trusel, Jonas Van Breedam, Peter Van Katwyk, Roderik S. W. van de Wal, Ricarda Winkelmann, Chen Zhao, Tong Zhang, and Thomas Zwinger
The Cryosphere, 17, 5197–5217, https://doi.org/10.5194/tc-17-5197-2023, https://doi.org/10.5194/tc-17-5197-2023, 2023
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Mass loss from Antarctica is a key contributor to sea level rise over the 21st century, and the associated uncertainty dominates sea level projections. We highlight here the Antarctic glaciers showing the largest changes and quantify the main sources of uncertainty in their future evolution using an ensemble of ice flow models. We show that on top of Pine Island and Thwaites glaciers, Totten and Moscow University glaciers show rapid changes and a strong sensitivity to warmer ocean conditions.
Uta Krebs-Kanzow, Christian B. Rodehacke, and Gerrit Lohmann
The Cryosphere, 17, 5131–5136, https://doi.org/10.5194/tc-17-5131-2023, https://doi.org/10.5194/tc-17-5131-2023, 2023
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We compare components of the surface energy balance from two datasets, ERA5 and ERA-Interim, which can be used to estimate the surface mass balance (SMB) on the Greenland Ice Sheet (GrIS). ERA5 differs significantly from ERA-Interim, especially in the melt regions with lower temperatures and stronger shortwave radiation. Consequently, methods that previously estimated the GrIS SMB from ERA-Interim need to be carefully recalibrated before conversion to ERA5 forcing.
Minjie Zheng, Hongyu Liu, Florian Adolphi, Raimund Muscheler, Zhengyao Lu, Mousong Wu, and Nønne L. Prisle
Geosci. Model Dev., 16, 7037–7057, https://doi.org/10.5194/gmd-16-7037-2023, https://doi.org/10.5194/gmd-16-7037-2023, 2023
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The radionuclides 7Be and 10Be are useful tracers for atmospheric transport studies. Here we use the GEOS-Chem to simulate 7Be and 10Be with different production rates: the default production rate in GEOS-Chem and two from the state-of-the-art beryllium production model. We demonstrate that reduced uncertainties in the production rates can enhance the utility of 7Be and 10Be as tracers for evaluating transport and scavenging processes in global models.
Michael Wolovick, Angelika Humbert, Thomas Kleiner, and Martin Rückamp
The Cryosphere, 17, 5027–5060, https://doi.org/10.5194/tc-17-5027-2023, https://doi.org/10.5194/tc-17-5027-2023, 2023
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The friction underneath ice sheets can be inferred from observed velocity at the top, but this inference requires smoothing. The selection of smoothing has been highly variable in the literature. Here we show how to rigorously select the best smoothing, and we show that the inferred friction converges towards the best knowable field as model resolution improves. We use this to learn about the best description of basal friction and to formulate recommended best practices for other modelers.
Ladina Steiner, Holger Schmithüsen, Jens Wickert, and Olaf Eisen
The Cryosphere, 17, 4903–4916, https://doi.org/10.5194/tc-17-4903-2023, https://doi.org/10.5194/tc-17-4903-2023, 2023
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The present study illustrates the potential of a combined Global Navigation Satellite System reflectometry and refractometry (GNSS-RR) method for accurate, simultaneous, and continuous estimation of in situ snow accumulation, snow water equivalent, and snow density time series. The combined GNSS-RR method was successfully applied on a fast-moving, polar ice shelf. The combined GNSS-RR approach could be highly advantageous for a continuous quantification of ice sheet surface mass balances.
Chiara I. Paleari, Florian Mekhaldi, Tobias Erhardt, Minjie Zheng, Marcus Christl, Florian Adolphi, Maria Hörhold, and Raimund Muscheler
Clim. Past, 19, 2409–2422, https://doi.org/10.5194/cp-19-2409-2023, https://doi.org/10.5194/cp-19-2409-2023, 2023
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In this study, we test the use of excess meltwater from continuous flow analysis from a firn core from Greenland for the measurement of 10Be for solar activity reconstructions. We show that the quality of results is similar to the measurements on clean firn, which opens the possibility to obtain continuous 10Be records without requiring large amounts of clean ice. Furthermore, we investigate the possibility of identifying solar storm signals in 10Be records from Greenland and Antarctica.
Tobias Erhardt, Camilla Marie Jensen, Florian Adolphi, Helle Astrid Kjær, Remi Dallmayr, Birthe Twarloh, Melanie Behrens, Motohiro Hirabayashi, Kaori Fukuda, Jun Ogata, François Burgay, Federico Scoto, Ilaria Crotti, Azzurra Spagnesi, Niccoló Maffezzoli, Delia Segato, Chiara Paleari, Florian Mekhaldi, Raimund Muscheler, Sophie Darfeuil, and Hubertus Fischer
Earth Syst. Sci. Data, 15, 5079–5091, https://doi.org/10.5194/essd-15-5079-2023, https://doi.org/10.5194/essd-15-5079-2023, 2023
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The presented paper provides a 3.8 kyr long dataset of aerosol concentrations from the East Greenland Ice coring Project (EGRIP) ice core. The data consists of 1 mm depth-resolution profiles of calcium, sodium, ammonium, nitrate, and electrolytic conductivity as well as decadal averages of these profiles. Alongside the data a detailed description of the measurement setup as well as a discussion of the uncertainties are given.
Luke Skinner, Francois Primeau, Aurich Jeltsch-Thömmes, Fortunat Joos, Peter Köhler, and Edouard Bard
Clim. Past, 19, 2177–2202, https://doi.org/10.5194/cp-19-2177-2023, https://doi.org/10.5194/cp-19-2177-2023, 2023
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Radiocarbon is best known as a dating tool, but it also allows us to track CO2 exchange between the ocean and atmosphere. Using decades of data and novel mapping methods, we have charted the ocean’s average radiocarbon ″age” since the last Ice Age. Combined with climate model simulations, these data quantify the ocean’s role in atmospheric CO2 rise since the last Ice Age while also revealing that Earth likely received far more cosmic radiation during the last Ice Age than hitherto believed.
Xiaoxu Shi, Martin Werner, Hu Yang, Roberta D'Agostino, Jiping Liu, Chaoyuan Yang, and Gerrit Lohmann
Clim. Past, 19, 2157–2175, https://doi.org/10.5194/cp-19-2157-2023, https://doi.org/10.5194/cp-19-2157-2023, 2023
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The Last Glacial Maximum (LGM) marks the most recent extremely cold and dry time period of our planet. Using AWI-ESM, we quantify the relative importance of Earth's orbit, greenhouse gases (GHG) and ice sheets (IS) in determining the LGM climate. Our results suggest that both GHG and IS play important roles in shaping the LGM temperature. Continental ice sheets exert a major control on precipitation, atmospheric dynamics, and the intensity of El Niño–Southern Oscillation.
Xin Ren, Daniel J. Lunt, Erica Hendy, Anna von der Heydt, Ayako Abe-Ouchi, Bette Otto-Bliesner, Charles J. R. Williams, Christian Stepanek, Chuncheng Guo, Deepak Chandan, Gerrit Lohmann, Julia C. Tindall, Linda E. Sohl, Mark A. Chandler, Masa Kageyama, Michiel L. J. Baatsen, Ning Tan, Qiong Zhang, Ran Feng, Stephen Hunter, Wing-Le Chan, W. Richard Peltier, Xiangyu Li, Youichi Kamae, Zhongshi Zhang, and Alan M. Haywood
Clim. Past, 19, 2053–2077, https://doi.org/10.5194/cp-19-2053-2023, https://doi.org/10.5194/cp-19-2053-2023, 2023
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We investigate the Maritime Continent climate in the mid-Piacenzian warm period and find it is warmer and wetter and the sea surface salinity is lower compared with preindustrial period. Besides, the fresh and warm water transfer through the Maritime Continent was stronger. In order to avoid undue influence from closely related models in the multimodel results, we introduce a new metric, the multi-cluster mean, which could reveal spatial signals that are not captured by the multimodel mean.
Ryan Love, Lev Tarasov, Heather Andres, Alan Condron, Xu Zhang, and Gerrit Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2023-2225, https://doi.org/10.5194/egusphere-2023-2225, 2023
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Freshwater injection into bands across the North Atlantic are a mainstay of climate modelling when investigating topics such as climate change or the role of glacial runoff in the glacial climate system. However, this approach is unrealistic and results in a systematic bias in the climate response to a given flux of freshwater. We evaluate the magnitude of this bias by comparison to two other approaches for introducing freshwater into a coupled climate model setup for glacial conditions.
Zhuo Wang, Ailsa Chung, Daniel Steinhage, Frédéric Parrenin, Johannes Freitag, and Olaf Eisen
The Cryosphere, 17, 4297–4314, https://doi.org/10.5194/tc-17-4297-2023, https://doi.org/10.5194/tc-17-4297-2023, 2023
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We combine radar-based observed internal layer stratigraphy of the ice sheet with a 1-D ice flow model in the Dome Fuji region. This results in maps of age and age density of the basal ice, the basal thermal conditions, and reconstructed accumulation rates. Based on modeled age we then identify four potential candidates for ice which is potentially 1.5 Myr old. Our map of basal thermal conditions indicates that melting prevails over the presence of stagnant ice in the study area.
Nora Hirsch, Alexandra Zuhr, Thomas Münch, Maria Hörhold, Johannes Freitag, Remi Dallmayr, and Thomas Laepple
The Cryosphere, 17, 4207–4221, https://doi.org/10.5194/tc-17-4207-2023, https://doi.org/10.5194/tc-17-4207-2023, 2023
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Stable water isotopes from firn cores provide valuable information on past climates, yet their utility is hampered by stratigraphic noise, i.e. the irregular deposition and wind-driven redistribution of snow. We found stratigraphic noise on the Antarctic Plateau to be related to the local accumulation rate, snow surface roughness and slope inclination, which can guide future decisions on sampling locations and thus increase the resolution of climate reconstructions from low-accumulation areas.
Julia Rieke Hagemann, Lester Lembke-Jene, Frank Lamy, Maria-Elena Vorrath, Jérôme Kaiser, Juliane Müller, Helge W. Arz, Jens Hefter, Andrea Jaeschke, Nicoletta Ruggieri, and Ralf Tiedemann
Clim. Past, 19, 1825–1845, https://doi.org/10.5194/cp-19-1825-2023, https://doi.org/10.5194/cp-19-1825-2023, 2023
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Alkenones and glycerol dialkyl glycerol tetraether lipids (GDGTs) are common biomarkers for past water temperatures. In high latitudes, determining temperature reliably is challenging. We analyzed 33 Southern Ocean sediment surface samples and evaluated widely used global calibrations for both biomarkers. For GDGT-based temperatures, previously used calibrations best reflect temperatures >5° C; (sub)polar temperature bias necessitates a new calibration which better aligns with modern values.
Claudia Hinrichs, Peter Köhler, Christoph Völker, and Judith Hauck
Biogeosciences, 20, 3717–3735, https://doi.org/10.5194/bg-20-3717-2023, https://doi.org/10.5194/bg-20-3717-2023, 2023
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This study evaluated the alkalinity distribution in 14 climate models and found that most models underestimate alkalinity at the surface and overestimate it in the deeper ocean. It highlights the need for better understanding and quantification of processes driving alkalinity distribution and calcium carbonate dissolution and the importance of accounting for biases in model results when evaluating potential ocean alkalinity enhancement experiments.
Yannic Fischler, Thomas Kleiner, Christian Bischof, Jeremie Schmiedel, Roiy Sayag, Raban Emunds, Lennart Frederik Oestreich, and Angelika Humbert
Geosci. Model Dev., 16, 5305–5322, https://doi.org/10.5194/gmd-16-5305-2023, https://doi.org/10.5194/gmd-16-5305-2023, 2023
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Water underneath ice sheets affects the motion of glaciers. This study presents a newly developed code, CUAS-MPI, that simulates subglacial hydrology. It is designed for supercomputers and is hence a parallelized code. We measure the performance of this code for simulations of the entire Greenland Ice Sheet and find that the code works efficiently. Moreover, we validated the code to ensure the correctness of the solution. CUAS-MPI opens new possibilities for simulations of ice sheet hydrology.
Xiaoxu Shi, Alexandre Cauquoin, Gerrit Lohmann, Lukas Jonkers, Qiang Wang, Hu Yang, Yuchen Sun, and Martin Werner
Geosci. Model Dev., 16, 5153–5178, https://doi.org/10.5194/gmd-16-5153-2023, https://doi.org/10.5194/gmd-16-5153-2023, 2023
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We developed a new climate model with isotopic capabilities and simulated the pre-industrial and mid-Holocene periods. Despite certain regional model biases, the modeled isotope composition is in good agreement with observations and reconstructions. Based on our analyses, the observed isotope–temperature relationship in polar regions may have a summertime bias. Using daily model outputs, we developed a novel isotope-based approach to determine the onset date of the West African summer monsoon.
Ailsa Chung, Frédéric Parrenin, Daniel Steinhage, Robert Mulvaney, Carlos Martín, Marie G. P. Cavitte, David A. Lilien, Veit Helm, Drew Taylor, Prasad Gogineni, Catherine Ritz, Massimo Frezzotti, Charles O'Neill, Heinrich Miller, Dorthe Dahl-Jensen, and Olaf Eisen
The Cryosphere, 17, 3461–3483, https://doi.org/10.5194/tc-17-3461-2023, https://doi.org/10.5194/tc-17-3461-2023, 2023
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We combined a numerical model with radar measurements in order to determine the age of ice in the Dome C region of Antarctica. Our results show that at the current ice core drilling sites on Little Dome C, the maximum age of the ice is almost 1.5 Ma. We also highlight a new potential drill site called North Patch with ice up to 2 Ma. Finally, we explore the nature of a stagnant ice layer at the base of the ice sheet which has been independently observed and modelled but is not well understood.
Nicolas Stoll, Matthias Wietz, Stephan Juricke, Franziska Pausch, Corina Peter, Miriam Seifert, Jana C. Massing, Moritz Zeising, Rebecca A. McPherson, Melissa Käß, and Björn Suckow
Polarforschung, 91, 31–43, https://doi.org/10.5194/polf-91-31-2023, https://doi.org/10.5194/polf-91-31-2023, 2023
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Global crises, such as climate change and the COVID-19 pandemic, show the importance of communicating science to the public. We introduce the YouTube channel "Wissenschaft fürs Wohnzimmer", which livestreams presentations on climate-related topics weekly and is accessible to all. The project encourages interaction between scientists and the public and has been running successfully for over 2 years. We present the concept, what we have learnt, and the challenges after 100 streamed episodes.
Di Cai, Gerrit Lohmann, Xianyao Chen, and Monica Ionita
EGUsphere, https://doi.org/10.5194/egusphere-2023-1646, https://doi.org/10.5194/egusphere-2023-1646, 2023
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Our study reveals how a decline in autumn sea ice in the Barents-Kara Seas leads to severe winters in Europe. Using observational data, we illustrate that Arctic sea ice loss isn't just a local issue – it impacts harsh winter conditions globally. Current climate models struggle to reflect these effects accurately, indicating a need for more research. Gaining a more nuanced understanding of this relationship will enhance our climate predictions and preparation for future extremes.
Alice C. Frémand, Peter Fretwell, Julien A. Bodart, Hamish D. Pritchard, Alan Aitken, Jonathan L. Bamber, Robin Bell, Cesidio Bianchi, Robert G. Bingham, Donald D. Blankenship, Gino Casassa, Ginny Catania, Knut Christianson, Howard Conway, Hugh F. J. Corr, Xiangbin Cui, Detlef Damaske, Volkmar Damm, Reinhard Drews, Graeme Eagles, Olaf Eisen, Hannes Eisermann, Fausto Ferraccioli, Elena Field, René Forsberg, Steven Franke, Shuji Fujita, Yonggyu Gim, Vikram Goel, Siva Prasad Gogineni, Jamin Greenbaum, Benjamin Hills, Richard C. A. Hindmarsh, Andrew O. Hoffman, Per Holmlund, Nicholas Holschuh, John W. Holt, Annika N. Horlings, Angelika Humbert, Robert W. Jacobel, Daniela Jansen, Adrian Jenkins, Wilfried Jokat, Tom Jordan, Edward King, Jack Kohler, William Krabill, Mette Kusk Gillespie, Kirsty Langley, Joohan Lee, German Leitchenkov, Carlton Leuschen, Bruce Luyendyk, Joseph MacGregor, Emma MacKie, Kenichi Matsuoka, Mathieu Morlighem, Jérémie Mouginot, Frank O. Nitsche, Yoshifumi Nogi, Ole A. Nost, John Paden, Frank Pattyn, Sergey V. Popov, Eric Rignot, David M. Rippin, Andrés Rivera, Jason Roberts, Neil Ross, Anotonia Ruppel, Dustin M. Schroeder, Martin J. Siegert, Andrew M. Smith, Daniel Steinhage, Michael Studinger, Bo Sun, Ignazio Tabacco, Kirsty Tinto, Stefano Urbini, David Vaughan, Brian C. Welch, Douglas S. Wilson, Duncan A. Young, and Achille Zirizzotti
Earth Syst. Sci. Data, 15, 2695–2710, https://doi.org/10.5194/essd-15-2695-2023, https://doi.org/10.5194/essd-15-2695-2023, 2023
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This paper presents the release of over 60 years of ice thickness, bed elevation, and surface elevation data acquired over Antarctica by the international community. These data are a crucial component of the Antarctic Bedmap initiative which aims to produce a new map and datasets of Antarctic ice thickness and bed topography for the international glaciology and geophysical community.
Angelika Humbert, Veit Helm, Niklas Neckel, Ole Zeising, Martin Rückamp, Shfaqat Abbas Khan, Erik Loebel, Jörg Brauchle, Karsten Stebner, Dietmar Gross, Rabea Sondershaus, and Ralf Müller
The Cryosphere, 17, 2851–2870, https://doi.org/10.5194/tc-17-2851-2023, https://doi.org/10.5194/tc-17-2851-2023, 2023
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The largest floating glacier mass in Greenland, the 79° N Glacier, is showing signs of instability. We investigate how crack formation at the glacier's calving front has changed over the last decades by using satellite imagery and airborne data. The calving front is about to lose contact to stabilizing ice islands. Simulations show that the glacier will accelerate as a result of this, leading to an increase in ice discharge of more than 5.1 % if its calving front retreats by 46 %.
Giulia Sinnl, Florian Adolphi, Marcus Christl, Kees C. Welten, Thomas Woodruff, Marc Caffee, Anders Svensson, Raimund Muscheler, and Sune Olander Rasmussen
Clim. Past, 19, 1153–1175, https://doi.org/10.5194/cp-19-1153-2023, https://doi.org/10.5194/cp-19-1153-2023, 2023
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The record of past climate is preserved by several archives from different regions, such as ice cores from Greenland or Antarctica or speleothems from caves such as the Hulu Cave in China. In this study, these archives are aligned by taking advantage of the globally synchronous production of cosmogenic radionuclides. This produces a new perspective on the global climate in the period between 20 000 and 25 000 years ago.
Maria-Elena Vorrath, Juliane Müller, Paola Cárdenas, Thomas Opel, Sebastian Mieruch, Oliver Esper, Lester Lembke-Jene, Johan Etourneau, Andrea Vieth-Hillebrand, Niko Lahajnar, Carina B. Lange, Amy Leventer, Dimitris Evangelinos, Carlota Escutia, and Gesine Mollenhauer
Clim. Past, 19, 1061–1079, https://doi.org/10.5194/cp-19-1061-2023, https://doi.org/10.5194/cp-19-1061-2023, 2023
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Sea ice is important to stabilize the ice sheet in Antarctica. To understand how the global climate and sea ice were related in the past we looked at ancient molecules (IPSO25) from sea-ice algae and other species whose dead cells accumulated on the ocean floor over time. With chemical analyses we could reconstruct the history of sea ice and ocean temperatures of the past 14 000 years. We found out that sea ice became less as the ocean warmed, and more phytoplankton grew towards today's level.
Heidi Kreibich, Kai Schröter, Giuliano Di Baldassarre, Anne F. Van Loon, Maurizio Mazzoleni, Guta Wakbulcho Abeshu, Svetlana Agafonova, Amir AghaKouchak, Hafzullah Aksoy, Camila Alvarez-Garreton, Blanca Aznar, Laila Balkhi, Marlies H. Barendrecht, Sylvain Biancamaria, Liduin Bos-Burgering, Chris Bradley, Yus Budiyono, Wouter Buytaert, Lucinda Capewell, Hayley Carlson, Yonca Cavus, Anaïs Couasnon, Gemma Coxon, Ioannis Daliakopoulos, Marleen C. de Ruiter, Claire Delus, Mathilde Erfurt, Giuseppe Esposito, Didier François, Frédéric Frappart, Jim Freer, Natalia Frolova, Animesh K. Gain, Manolis Grillakis, Jordi Oriol Grima, Diego A. Guzmán, Laurie S. Huning, Monica Ionita, Maxim Kharlamov, Dao Nguyen Khoi, Natalie Kieboom, Maria Kireeva, Aristeidis Koutroulis, Waldo Lavado-Casimiro, Hong-Yi Li, Maria Carmen LLasat, David Macdonald, Johanna Mård, Hannah Mathew-Richards, Andrew McKenzie, Alfonso Mejia, Eduardo Mario Mendiondo, Marjolein Mens, Shifteh Mobini, Guilherme Samprogna Mohor, Viorica Nagavciuc, Thanh Ngo-Duc, Huynh Thi Thao Nguyen, Pham Thi Thao Nhi, Olga Petrucci, Nguyen Hong Quan, Pere Quintana-Seguí, Saman Razavi, Elena Ridolfi, Jannik Riegel, Md Shibly Sadik, Nivedita Sairam, Elisa Savelli, Alexey Sazonov, Sanjib Sharma, Johanna Sörensen, Felipe Augusto Arguello Souza, Kerstin Stahl, Max Steinhausen, Michael Stoelzle, Wiwiana Szalińska, Qiuhong Tang, Fuqiang Tian, Tamara Tokarczyk, Carolina Tovar, Thi Van Thu Tran, Marjolein H. J. van Huijgevoort, Michelle T. H. van Vliet, Sergiy Vorogushyn, Thorsten Wagener, Yueling Wang, Doris E. Wendt, Elliot Wickham, Long Yang, Mauricio Zambrano-Bigiarini, and Philip J. Ward
Earth Syst. Sci. Data, 15, 2009–2023, https://doi.org/10.5194/essd-15-2009-2023, https://doi.org/10.5194/essd-15-2009-2023, 2023
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As the adverse impacts of hydrological extremes increase in many regions of the world, a better understanding of the drivers of changes in risk and impacts is essential for effective flood and drought risk management. We present a dataset containing data of paired events, i.e. two floods or two droughts that occurred in the same area. The dataset enables comparative analyses and allows detailed context-specific assessments. Additionally, it supports the testing of socio-hydrological models.
Nicolas Stoll, Julien Westhoff, Pascal Bohleber, Anders Svensson, Dorthe Dahl-Jensen, Carlo Barbante, and Ilka Weikusat
The Cryosphere, 17, 2021–2043, https://doi.org/10.5194/tc-17-2021-2023, https://doi.org/10.5194/tc-17-2021-2023, 2023
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Impurities in polar ice play a role regarding its climate signal and internal deformation. We bridge different scales using different methods to investigate ice from the Last Glacial Period derived from the EGRIP ice core in Greenland. We characterise different types of cloudy bands, i.e. frequently occurring milky layers in the ice, and analyse their chemistry with Raman spectroscopy and 2D imaging. We derive new insights into impurity localisation and deposition conditions.
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, and David H. Roberts
The Cryosphere, 17, 1821–1837, https://doi.org/10.5194/tc-17-1821-2023, https://doi.org/10.5194/tc-17-1821-2023, 2023
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The Northeast Greenland Ice Stream is a major outlet of the Greenland Ice Sheet. Some of its outlet glaciers and ice shelves have been breaking up and retreating, with inflows of warm ocean water identified as the likely reason. Here we report direct measurements of warm ocean water in an unusual lake that is connected to the ocean beneath the ice shelf in front of the 79° N Glacier. This glacier has not yet shown much retreat, but the presence of warm water makes future retreat more likely.
Inès N. Otosaka, Andrew Shepherd, Erik R. Ivins, Nicole-Jeanne Schlegel, Charles Amory, Michiel R. van den Broeke, Martin Horwath, Ian Joughin, Michalea D. King, Gerhard Krinner, Sophie Nowicki, Anthony J. Payne, Eric Rignot, Ted Scambos, Karen M. Simon, Benjamin E. Smith, Louise S. Sørensen, Isabella Velicogna, Pippa L. Whitehouse, Geruo A, Cécile Agosta, Andreas P. Ahlstrøm, Alejandro Blazquez, William Colgan, Marcus E. Engdahl, Xavier Fettweis, Rene Forsberg, Hubert Gallée, Alex Gardner, Lin Gilbert, Noel Gourmelen, Andreas Groh, Brian C. Gunter, Christopher Harig, Veit Helm, Shfaqat Abbas Khan, Christoph Kittel, Hannes Konrad, Peter L. Langen, Benoit S. Lecavalier, Chia-Chun Liang, Bryant D. Loomis, Malcolm McMillan, Daniele Melini, Sebastian H. Mernild, Ruth Mottram, Jeremie Mouginot, Johan Nilsson, Brice Noël, Mark E. Pattle, William R. Peltier, Nadege Pie, Mònica Roca, Ingo Sasgen, Himanshu V. Save, Ki-Weon Seo, Bernd Scheuchl, Ernst J. O. Schrama, Ludwig Schröder, Sebastian B. Simonsen, Thomas Slater, Giorgio Spada, Tyler C. Sutterley, Bramha Dutt Vishwakarma, Jan Melchior van Wessem, David Wiese, Wouter van der Wal, and Bert Wouters
Earth Syst. Sci. Data, 15, 1597–1616, https://doi.org/10.5194/essd-15-1597-2023, https://doi.org/10.5194/essd-15-1597-2023, 2023
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By measuring changes in the volume, gravitational attraction, and ice flow of Greenland and Antarctica from space, we can monitor their mass gain and loss over time. Here, we present a new record of the Earth’s polar ice sheet mass balance produced by aggregating 50 satellite-based estimates of ice sheet mass change. This new assessment shows that the ice sheets have lost (7.5 x 1012) t of ice between 1992 and 2020, contributing 21 mm to sea level rise.
Olga Ogneva, Gesine Mollenhauer, Bennet Juhls, Tina Sanders, Juri Palmtag, Matthias Fuchs, Hendrik Grotheer, Paul J. Mann, and Jens Strauss
Biogeosciences, 20, 1423–1441, https://doi.org/10.5194/bg-20-1423-2023, https://doi.org/10.5194/bg-20-1423-2023, 2023
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Arctic warming accelerates permafrost thaw and release of terrestrial organic matter (OM) via rivers to the Arctic Ocean. We compared particulate organic carbon (POC), total suspended matter, and C isotopes (δ13C and Δ14C of POC) in the Lena delta and Lena River along a ~1600 km transect. We show that the Lena delta, as an interface between the Lena River and the Arctic Ocean, plays a crucial role in determining the qualitative and quantitative composition of OM discharged into the Arctic Ocean.
Felix Pithan, Marylou Athanase, Sandro Dahlke, Antonio Sánchez-Benítez, Matthew D. Shupe, Anne Sledd, Jan Streffing, Gunilla Svensson, and Thomas Jung
Geosci. Model Dev., 16, 1857–1873, https://doi.org/10.5194/gmd-16-1857-2023, https://doi.org/10.5194/gmd-16-1857-2023, 2023
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Evaluating climate models usually requires long observational time series, but we present a method that also works for short field campaigns. We compare climate model output to observations from the MOSAiC expedition in the central Arctic Ocean. All models show how the arrival of a warm air mass warms the Arctic in April 2020, but two models do not show the response of snow temperature to the diurnal cycle. One model has too little liquid water and too much ice in clouds during cold days.
Romilly Harris Stuart, Anne-Katrine Faber, Sonja Wahl, Maria Hörhold, Sepp Kipfstuhl, Kristian Vasskog, Melanie Behrens, Alexandra M. Zuhr, and Hans Christian Steen-Larsen
The Cryosphere, 17, 1185–1204, https://doi.org/10.5194/tc-17-1185-2023, https://doi.org/10.5194/tc-17-1185-2023, 2023
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This empirical study uses continuous daily measurements from the Greenland Ice Sheet to document changes in surface snow properties. Consistent changes in snow isotopic composition are observed in the absence of deposition due to surface processes, indicating the isotopic signal of deposited precipitation is not always preserved. Our observations have potential implications for the interpretation of water isotopes in ice cores – historically assumed to reflect isotopic composition at deposition.
Ole Zeising, Tamara Annina Gerber, Olaf Eisen, M. Reza Ershadi, Nicolas Stoll, Ilka Weikusat, and Angelika Humbert
The Cryosphere, 17, 1097–1105, https://doi.org/10.5194/tc-17-1097-2023, https://doi.org/10.5194/tc-17-1097-2023, 2023
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The flow of glaciers and ice streams is influenced by crystal fabric orientation. Besides sparse ice cores, these can be investigated by radar measurements. Here, we present an improved method which allows us to infer the horizontal fabric asymmetry using polarimetric phase-sensitive radar data. A validation of the method on a deep ice core from the Greenland Ice Sheet shows an excellent agreement, which is a large improvement over previously used methods.
Mengli Cao, Jens Hefter, Ralf Tiedemann, Lester Lembke-Jene, Vera D. Meyer, and Gesine Mollenhauer
Clim. Past, 19, 159–178, https://doi.org/10.5194/cp-19-159-2023, https://doi.org/10.5194/cp-19-159-2023, 2023
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We use sediment records of lignin to reconstruct deglacial vegetation change and permafrost mobilization, which occurred earlier in the Yukon than in the Amur river basin. Sea ice extent or surface temperatures of adjacent oceans might have had a strong influence on the timing of permafrost mobilization. In contrast to previous evidence, our records imply that during glacial peaks of permafrost decomposition, lipids and lignin might have been delivered to the ocean by identical processes.
Pengyang Song, Dmitry Sidorenko, Patrick Scholz, Maik Thomas, and Gerrit Lohmann
Geosci. Model Dev., 16, 383–405, https://doi.org/10.5194/gmd-16-383-2023, https://doi.org/10.5194/gmd-16-383-2023, 2023
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Tides have essential effects on the ocean and climate. Most previous research applies parameterised tidal mixing to discuss their effects in models. By comparing the effect of a tidal mixing parameterisation and tidal forcing on the ocean state, we assess the advantages and disadvantages of the two methods. Our results show that tidal mixing in the North Pacific Ocean strongly affects the global thermohaline circulation. We also list some effects that are not considered in the parameterisation.
Francesca Doglioni, Robert Ricker, Benjamin Rabe, Alexander Barth, Charles Troupin, and Torsten Kanzow
Earth Syst. Sci. Data, 15, 225–263, https://doi.org/10.5194/essd-15-225-2023, https://doi.org/10.5194/essd-15-225-2023, 2023
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This paper presents a new satellite-derived gridded dataset, including 10 years of sea surface height and geostrophic velocity at monthly resolution, over the Arctic ice-covered and ice-free regions, up to 88° N. We assess the dataset by comparison to independent satellite and mooring data. Results correlate well with independent satellite data at monthly timescales, and the geostrophic velocity fields can resolve seasonal to interannual variability of boundary currents wider than about 50 km.
Julia E. Weiffenbach, Michiel L. J. Baatsen, Henk A. Dijkstra, Anna S. von der Heydt, Ayako Abe-Ouchi, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Mark A. Chandler, Camille Contoux, Ran Feng, Chuncheng Guo, Zixuan Han, Alan M. Haywood, Qiang Li, Xiangyu Li, Gerrit Lohmann, Daniel J. Lunt, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Gilles Ramstein, Linda E. Sohl, Christian Stepanek, Ning Tan, Julia C. Tindall, Charles J. R. Williams, Qiong Zhang, and Zhongshi Zhang
Clim. Past, 19, 61–85, https://doi.org/10.5194/cp-19-61-2023, https://doi.org/10.5194/cp-19-61-2023, 2023
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We study the behavior of the Atlantic Meridional Overturning Circulation (AMOC) in the mid-Pliocene. The mid-Pliocene was about 3 million years ago and had a similar CO2 concentration to today. We show that the stronger AMOC during this period relates to changes in geography and that this has a significant influence on ocean temperatures and heat transported northwards by the Atlantic Ocean. Understanding the behavior of the mid-Pliocene AMOC can help us to learn more about our future climate.
Julian Gutt, Stefanie Arndt, David Keith Alan Barnes, Horst Bornemann, Thomas Brey, Olaf Eisen, Hauke Flores, Huw Griffiths, Christian Haas, Stefan Hain, Tore Hattermann, Christoph Held, Mario Hoppema, Enrique Isla, Markus Janout, Céline Le Bohec, Heike Link, Felix Christopher Mark, Sebastien Moreau, Scarlett Trimborn, Ilse van Opzeeland, Hans-Otto Pörtner, Fokje Schaafsma, Katharina Teschke, Sandra Tippenhauer, Anton Van de Putte, Mia Wege, Daniel Zitterbart, and Dieter Piepenburg
Biogeosciences, 19, 5313–5342, https://doi.org/10.5194/bg-19-5313-2022, https://doi.org/10.5194/bg-19-5313-2022, 2022
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Long-term ecological observations are key to assess, understand and predict impacts of environmental change on biotas. We present a multidisciplinary framework for such largely lacking investigations in the East Antarctic Southern Ocean, combined with case studies, experimental and modelling work. As climate change is still minor here but is projected to start soon, the timely implementation of this framework provides the unique opportunity to document its ecological impacts from the very onset.
Vjeran Višnjević, Reinhard Drews, Clemens Schannwell, Inka Koch, Steven Franke, Daniela Jansen, and Olaf Eisen
The Cryosphere, 16, 4763–4777, https://doi.org/10.5194/tc-16-4763-2022, https://doi.org/10.5194/tc-16-4763-2022, 2022
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We present a simple way to model the internal layers of an ice shelf and apply the method to the Roi Baudouin Ice Shelf in East Antarctica. Modeled results are compared to measurements obtained by radar. We distinguish between ice directly formed on the shelf and ice transported from the ice sheet, and we map the spatial changes in the volume of the locally accumulated ice. In this context, we discuss the sensitivity of the ice shelf to future changes in surface accumulation and basal melt.
Antoine Grisart, Mathieu Casado, Vasileios Gkinis, Bo Vinther, Philippe Naveau, Mathieu Vrac, Thomas Laepple, Bénédicte Minster, Frederic Prié, Barbara Stenni, Elise Fourré, Hans Christian Steen-Larsen, Jean Jouzel, Martin Werner, Katy Pol, Valérie Masson-Delmotte, Maria Hoerhold, Trevor Popp, and Amaelle Landais
Clim. Past, 18, 2289–2301, https://doi.org/10.5194/cp-18-2289-2022, https://doi.org/10.5194/cp-18-2289-2022, 2022
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This paper presents a compilation of high-resolution (11 cm) water isotopic records, including published and new measurements, for the last 800 000 years from the EPICA Dome C ice core, Antarctica. Using this new combined water isotopes (δ18O and δD) dataset, we study the variability and possible influence of diffusion at the multi-decadal to multi-centennial scale. We observe a stronger variability at the onset of the interglacial interval corresponding to a warm period.
Angelika Humbert, Julia Christmann, Hugh F. J. Corr, Veit Helm, Lea-Sophie Höyns, Coen Hofstede, Ralf Müller, Niklas Neckel, Keith W. Nicholls, Timm Schultz, Daniel Steinhage, Michael Wolovick, and Ole Zeising
The Cryosphere, 16, 4107–4139, https://doi.org/10.5194/tc-16-4107-2022, https://doi.org/10.5194/tc-16-4107-2022, 2022
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Ice shelves are normally flat structures that fringe the Antarctic continent. At some locations they have channels incised into their underside. On Filchner Ice Shelf, such a channel is more than 50 km long and up to 330 m high. We conducted field measurements of basal melt rates and found a maximum of 2 m yr−1. Simulations represent the geometry evolution of the channel reasonably well. There is no reason to assume that this type of melt channel is destabilizing ice shelves.
Jan Streffing, Dmitry Sidorenko, Tido Semmler, Lorenzo Zampieri, Patrick Scholz, Miguel Andrés-Martínez, Nikolay Koldunov, Thomas Rackow, Joakim Kjellsson, Helge Goessling, Marylou Athanase, Qiang Wang, Jan Hegewald, Dmitry V. Sein, Longjiang Mu, Uwe Fladrich, Dirk Barbi, Paul Gierz, Sergey Danilov, Stephan Juricke, Gerrit Lohmann, and Thomas Jung
Geosci. Model Dev., 15, 6399–6427, https://doi.org/10.5194/gmd-15-6399-2022, https://doi.org/10.5194/gmd-15-6399-2022, 2022
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We developed a new atmosphere–ocean coupled climate model, AWI-CM3. Our model is significantly more computationally efficient than its predecessors AWI-CM1 and AWI-CM2. We show that the model, although cheaper to run, provides results of similar quality when modeling the historic period from 1850 to 2014. We identify the remaining weaknesses to outline future work. Finally we preview an improved simulation where the reduction in computational cost has to be invested in higher model resolution.
Helen Eri Amsler, Lena Mareike Thöle, Ingrid Stimac, Walter Geibert, Minoru Ikehara, Gerhard Kuhn, Oliver Esper, and Samuel Laurent Jaccard
Clim. Past, 18, 1797–1813, https://doi.org/10.5194/cp-18-1797-2022, https://doi.org/10.5194/cp-18-1797-2022, 2022
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We present sedimentary redox-sensitive trace metal records from five sediment cores retrieved from the SW Indian Ocean. These records are indicative of oxygen-depleted conditions during cold periods and enhanced oxygenation during interstadials. Our results thus suggest that deep-ocean oxygenation changes were mainly controlled by ocean ventilation and that a generally more sluggish circulation contributed to sequestering remineralized carbon away from the atmosphere during glacial periods.
Xavier Crosta, Karen E. Kohfeld, Helen C. Bostock, Matthew Chadwick, Alice Du Vivier, Oliver Esper, Johan Etourneau, Jacob Jones, Amy Leventer, Juliane Müller, Rachael H. Rhodes, Claire S. Allen, Pooja Ghadi, Nele Lamping, Carina B. Lange, Kelly-Anne Lawler, David Lund, Alice Marzocchi, Katrin J. Meissner, Laurie Menviel, Abhilash Nair, Molly Patterson, Jennifer Pike, Joseph G. Prebble, Christina Riesselman, Henrik Sadatzki, Louise C. Sime, Sunil K. Shukla, Lena Thöle, Maria-Elena Vorrath, Wenshen Xiao, and Jiao Yang
Clim. Past, 18, 1729–1756, https://doi.org/10.5194/cp-18-1729-2022, https://doi.org/10.5194/cp-18-1729-2022, 2022
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Despite its importance in the global climate, our knowledge of Antarctic sea-ice changes throughout the last glacial–interglacial cycle is extremely limited. As part of the Cycles of Sea Ice Dynamics in the Earth system (C-SIDE) Working Group, we review marine- and ice-core-based sea-ice proxies to provide insights into their applicability and limitations. By compiling published records, we provide information on Antarctic sea-ice dynamics over the past 130 000 years.
Simon Felix Reifenberg and Helge Friedrich Goessling
The Cryosphere, 16, 2927–2946, https://doi.org/10.5194/tc-16-2927-2022, https://doi.org/10.5194/tc-16-2927-2022, 2022
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Using model simulations, we analyze the impact of chaotic error growth on Arctic sea ice drift predictions. Regarding forecast uncertainty, our results suggest that it matters in which season and where ice drift forecasts are initialized and that both factors vary with the model in use. We find ice velocities to be slightly more predictable than near-surface wind, a main driver of ice drift. This is relevant for future developments of ice drift forecasting systems.
Gilles Reverdin, Claire Waelbroeck, Catherine Pierre, Camille Akhoudas, Giovanni Aloisi, Marion Benetti, Bernard Bourlès, Magnus Danielsen, Jérôme Demange, Denis Diverrès, Jean-Claude Gascard, Marie-Noëlle Houssais, Hervé Le Goff, Pascale Lherminier, Claire Lo Monaco, Herlé Mercier, Nicolas Metzl, Simon Morisset, Aïcha Naamar, Thierry Reynaud, Jean-Baptiste Sallée, Virginie Thierry, Susan E. Hartman, Edward W. Mawji, Solveig Olafsdottir, Torsten Kanzow, Anton Velo, Antje Voelker, Igor Yashayaev, F. Alexander Haumann, Melanie J. Leng, Carol Arrowsmith, and Michael Meredith
Earth Syst. Sci. Data, 14, 2721–2735, https://doi.org/10.5194/essd-14-2721-2022, https://doi.org/10.5194/essd-14-2721-2022, 2022
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The CISE-LOCEAN seawater stable isotope dataset has close to 8000 data entries. The δ18O and δD isotopic data measured at LOCEAN have uncertainties of at most 0.05 ‰ and 0.25 ‰, respectively. Some data were adjusted to correct for evaporation. The internal consistency indicates that the data can be used to investigate time and space variability to within 0.03 ‰ and 0.15 ‰ in δ18O–δD17; comparisons with data analyzed in other institutions suggest larger differences with other datasets.
Stefan Mulitza, Torsten Bickert, Helen C. Bostock, Cristiano M. Chiessi, Barbara Donner, Aline Govin, Naomi Harada, Enqing Huang, Heather Johnstone, Henning Kuhnert, Michael Langner, Frank Lamy, Lester Lembke-Jene, Lorraine Lisiecki, Jean Lynch-Stieglitz, Lars Max, Mahyar Mohtadi, Gesine Mollenhauer, Juan Muglia, Dirk Nürnberg, André Paul, Carsten Rühlemann, Janne Repschläger, Rajeev Saraswat, Andreas Schmittner, Elisabeth L. Sikes, Robert F. Spielhagen, and Ralf Tiedemann
Earth Syst. Sci. Data, 14, 2553–2611, https://doi.org/10.5194/essd-14-2553-2022, https://doi.org/10.5194/essd-14-2553-2022, 2022
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Stable isotope ratios of foraminiferal shells from deep-sea sediments preserve key information on the variability of ocean circulation and ice volume. We present the first global atlas of harmonized raw downcore oxygen and carbon isotope ratios of various planktonic and benthic foraminiferal species. The atlas is a foundation for the analyses of the history of Earth system components, for finding future coring sites, and for teaching marine stratigraphy and paleoceanography.
Astrid Oetting, Emma C. Smith, Jan Erik Arndt, Boris Dorschel, Reinhard Drews, Todd A. Ehlers, Christoph Gaedicke, Coen Hofstede, Johann P. Klages, Gerhard Kuhn, Astrid Lambrecht, Andreas Läufer, Christoph Mayer, Ralf Tiedemann, Frank Wilhelms, and Olaf Eisen
The Cryosphere, 16, 2051–2066, https://doi.org/10.5194/tc-16-2051-2022, https://doi.org/10.5194/tc-16-2051-2022, 2022
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This study combines a variety of geophysical measurements in front of and beneath the Ekström Ice Shelf in order to identify and interpret geomorphological evidences of past ice sheet flow, extent and retreat.
The maximal extent of grounded ice in this region was 11 km away from the continental shelf break.
The thickness of palaeo-ice on the calving front around the LGM was estimated to be at least 305 to 320 m.
We provide essential boundary conditions for palaeo-ice-sheet models.
Maria-Gema Llorens, Albert Griera, Paul D. Bons, Ilka Weikusat, David J. Prior, Enrique Gomez-Rivas, Tamara de Riese, Ivone Jimenez-Munt, Daniel García-Castellanos, and Ricardo A. Lebensohn
The Cryosphere, 16, 2009–2024, https://doi.org/10.5194/tc-16-2009-2022, https://doi.org/10.5194/tc-16-2009-2022, 2022
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Polar ice is formed by ice crystals, which form fabrics that are utilised to interpret how ice sheets flow. It is unclear whether fabrics result from the current flow regime or if they are inherited. To understand the extent to which ice crystals can be reoriented when ice flow conditions change, we simulate and evaluate multi-stage ice flow scenarios according to natural cases. We find that second deformation regimes normally overprint inherited fabrics, with a range of transitional fabrics.
Xiaoxu Shi, Martin Werner, Carolin Krug, Chris M. Brierley, Anni Zhao, Endurance Igbinosa, Pascale Braconnot, Esther Brady, Jian Cao, Roberta D'Agostino, Johann Jungclaus, Xingxing Liu, Bette Otto-Bliesner, Dmitry Sidorenko, Robert Tomas, Evgeny M. Volodin, Hu Yang, Qiong Zhang, Weipeng Zheng, and Gerrit Lohmann
Clim. Past, 18, 1047–1070, https://doi.org/10.5194/cp-18-1047-2022, https://doi.org/10.5194/cp-18-1047-2022, 2022
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Since the orbital parameters of the past are different from today, applying the modern calendar to the past climate can lead to an artificial bias in seasonal cycles. With the use of multiple model outputs, we found that such a bias is non-ignorable and should be corrected to ensure an accurate comparison between modeled results and observational records, as well as between simulated past and modern climates, especially for the Last Interglacial.
Julien Westhoff, Giulia Sinnl, Anders Svensson, Johannes Freitag, Helle Astrid Kjær, Paul Vallelonga, Bo Vinther, Sepp Kipfstuhl, Dorthe Dahl-Jensen, and Ilka Weikusat
Clim. Past, 18, 1011–1034, https://doi.org/10.5194/cp-18-1011-2022, https://doi.org/10.5194/cp-18-1011-2022, 2022
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We present a melt event record from an ice core from central Greenland, which covers the past 10 000 years. Our record displays warm summer events, which can be used to enhance our understanding of the past climate. We compare our data to anomalies in tree ring width, which also represents summer temperatures, and find a good correlation. Furthermore, we investigate an outstandingly warm event in the year 986 AD or 991 AD, which has not been analyzed before.
Yannic Fischler, Martin Rückamp, Christian Bischof, Vadym Aizinger, Mathieu Morlighem, and Angelika Humbert
Geosci. Model Dev., 15, 3753–3771, https://doi.org/10.5194/gmd-15-3753-2022, https://doi.org/10.5194/gmd-15-3753-2022, 2022
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Ice sheet models are used to simulate the changes of ice sheets in future but are currently often run in coarse resolution and/or with neglecting important physics to make them affordable in terms of computational costs. We conducted a study simulating the Greenland Ice Sheet in high resolution and adequate physics to test where the ISSM ice sheet code is using most time and what could be done to improve its performance for future computer architectures that allow massive parallel computing.
M. Reza Ershadi, Reinhard Drews, Carlos Martín, Olaf Eisen, Catherine Ritz, Hugh Corr, Julia Christmann, Ole Zeising, Angelika Humbert, and Robert Mulvaney
The Cryosphere, 16, 1719–1739, https://doi.org/10.5194/tc-16-1719-2022, https://doi.org/10.5194/tc-16-1719-2022, 2022
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Radio waves transmitted through ice split up and inform us about the ice sheet interior and orientation of single ice crystals. This can be used to infer how ice flows and improve projections on how it will evolve in the future. Here we used an inverse approach and developed a new algorithm to infer ice properties from observed radar data. We applied this technique to the radar data obtained at two EPICA drilling sites, where ice cores were used to validate our results.
Martin Rückamp, Thomas Kleiner, and Angelika Humbert
The Cryosphere, 16, 1675–1696, https://doi.org/10.5194/tc-16-1675-2022, https://doi.org/10.5194/tc-16-1675-2022, 2022
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We present a comparative modelling study between the full-Stokes (FS) and Blatter–Pattyn (BP) approximation applied to the Northeast Greenland Ice Stream. Both stress regimes are implemented in one single ice sheet code to eliminate numerical issues. The simulations unveil minor differences in the upper ice stream but become considerable at the grounding line of the 79° North Glacier. Model differences are stronger for a power-law friction than a linear friction law.
Ole Zeising, Daniel Steinhage, Keith W. Nicholls, Hugh F. J. Corr, Craig L. Stewart, and Angelika Humbert
The Cryosphere, 16, 1469–1482, https://doi.org/10.5194/tc-16-1469-2022, https://doi.org/10.5194/tc-16-1469-2022, 2022
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Remote-sensing-derived basal melt rates of ice shelves are of great importance due to their capability to cover larger areas. We performed in situ measurements with a phase-sensitive radar on the southern Filchner Ice Shelf, showing moderate melt rates and low small-scale spatial variability. The comparison with remote-sensing-based melt rates revealed large differences caused by the estimation of vertical strain rates from remote sensing velocity fields that modern fields can overcome.
Ryan A. Green, Laurie Menviel, Katrin J. Meissner, Xavier Crosta, Deepak Chandan, Gerrit Lohmann, W. Richard Peltier, Xiaoxu Shi, and Jiang Zhu
Clim. Past, 18, 845–862, https://doi.org/10.5194/cp-18-845-2022, https://doi.org/10.5194/cp-18-845-2022, 2022
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Climate models are used to predict future climate changes and as such, it is important to assess their performance in simulating past climate changes. We analyze seasonal sea-ice cover over the Southern Ocean simulated from numerical PMIP3, PMIP4 and LOVECLIM simulations during the Last Glacial Maximum (LGM). Comparing these simulations to proxy data, we provide improved estimates of LGM seasonal sea-ice cover. Our estimate of summer sea-ice extent is 20 %–30 % larger than previous estimates.
Charlotte Haugk, Loeka L. Jongejans, Kai Mangelsdorf, Matthias Fuchs, Olga Ogneva, Juri Palmtag, Gesine Mollenhauer, Paul J. Mann, P. Paul Overduin, Guido Grosse, Tina Sanders, Robyn E. Tuerena, Lutz Schirrmeister, Sebastian Wetterich, Alexander Kizyakov, Cornelia Karger, and Jens Strauss
Biogeosciences, 19, 2079–2094, https://doi.org/10.5194/bg-19-2079-2022, https://doi.org/10.5194/bg-19-2079-2022, 2022
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Buried animal and plant remains (carbon) from the last ice age were freeze-locked in permafrost. At an extremely fast eroding permafrost cliff in the Lena Delta (Siberia), we found this formerly frozen carbon well preserved. Our results show that ongoing degradation releases substantial amounts of this carbon, making it available for future carbon emissions. This mobilisation at the studied cliff and also similarly eroding sites bear the potential to affect rivers and oceans negatively.
Viorica Nagavciuc, Patrick Scholz, and Monica Ionita
Nat. Hazards Earth Syst. Sci., 22, 1347–1369, https://doi.org/10.5194/nhess-22-1347-2022, https://doi.org/10.5194/nhess-22-1347-2022, 2022
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Here we have assessed the variability and trends of hot and dry summers in Romania. The length, spatial extent, and frequency of heat waves in Romania have increased significantly over the last 70 years, while no significant changes have been observed in the drought conditions. The increased frequency of heat waves, especially after the 1990s, could be partially explained by an increase in the geopotential height over the eastern part of Europe.
Sara Pasqualetto, Luisa Cristini, and Thomas Jung
Geosci. Commun., 5, 87–100, https://doi.org/10.5194/gc-5-87-2022, https://doi.org/10.5194/gc-5-87-2022, 2022
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Many projects in their reporting phase are required to provide a clear plan for evaluating the results of those efforts aimed at translating scientific results to a broader audience. This paper illustrates methodologies and strategies used in the framework of a European research project to assess the impact of knowledge transfer activities, both quantitatively and qualitatively, and provides recommendations and hints for developing a useful impact plan for scientific projects.
Gerard J. M. Versteegh, Karin A. F. Zonneveld, Jens Hefter, Oscar E. Romero, Gerhard Fischer, and Gesine Mollenhauer
Biogeosciences, 19, 1587–1610, https://doi.org/10.5194/bg-19-1587-2022, https://doi.org/10.5194/bg-19-1587-2022, 2022
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A 5-year record of long-chain mid-chain diol export flux and composition is presented with a 1- to 3-week resolution sediment trap CBeu (in the NW African upwelling). All environmental parameters as well as the diol composition are dominated by the seasonal cycle, albeit with different phase relations for temperature and upwelling. Most diol-based proxies are dominated by upwelling. The long-chain diol index reflects temperatures of the oligotrophic summer sea surface.
Sebastian Hinck, Evan J. Gowan, Xu Zhang, and Gerrit Lohmann
The Cryosphere, 16, 941–965, https://doi.org/10.5194/tc-16-941-2022, https://doi.org/10.5194/tc-16-941-2022, 2022
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Proglacial lakes were pervasive along the retreating continental ice margins after the Last Glacial Maximum. Similarly to the marine ice boundary, interactions at the ice-lake interface impact ice sheet dynamics and mass balance. Previous numerical ice sheet modeling studies did not include a dynamical lake boundary. We describe the implementation of an adaptive lake boundary condition in PISM and apply the model to the glacial retreat of the Laurentide Ice Sheet.
Klaus Dethloff, Wieslaw Maslowski, Stefan Hendricks, Younjoo J. Lee, Helge F. Goessling, Thomas Krumpen, Christian Haas, Dörthe Handorf, Robert Ricker, Vladimir Bessonov, John J. Cassano, Jaclyn Clement Kinney, Robert Osinski, Markus Rex, Annette Rinke, Julia Sokolova, and Anja Sommerfeld
The Cryosphere, 16, 981–1005, https://doi.org/10.5194/tc-16-981-2022, https://doi.org/10.5194/tc-16-981-2022, 2022
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Sea ice thickness anomalies during the MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) winter in January, February and March 2020 were simulated with the coupled Regional Arctic climate System Model (RASM) and compared with CryoSat-2/SMOS satellite data. Hindcast and ensemble simulations indicate that the sea ice anomalies are driven by nonlinear interactions between ice growth processes and wind-driven sea-ice transports, with dynamics playing a dominant role.
Justus Contzen, Thorsten Dickhaus, and Gerrit Lohmann
Geosci. Model Dev., 15, 1803–1820, https://doi.org/10.5194/gmd-15-1803-2022, https://doi.org/10.5194/gmd-15-1803-2022, 2022
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Climate models are of paramount importance to predict future climate changes. Since many severe consequences of climate change are due to extreme events, the accurate behaviour of models in terms of extremes needs to be validated thoroughly. We present a method for model validation in terms of climate extremes and an algorithm to detect regions in which extremes tend to occur at the same time. These methods are applied to data from different climate models and to observational data.
Molly O. Patterson, Richard H. Levy, Denise K. Kulhanek, Tina van de Flierdt, Huw Horgan, Gavin B. Dunbar, Timothy R. Naish, Jeanine Ash, Alex Pyne, Darcy Mandeno, Paul Winberry, David M. Harwood, Fabio Florindo, Francisco J. Jimenez-Espejo, Andreas Läufer, Kyu-Cheul Yoo, Osamu Seki, Paolo Stocchi, Johann P. Klages, Jae Il Lee, Florence Colleoni, Yusuke Suganuma, Edward Gasson, Christian Ohneiser, José-Abel Flores, David Try, Rachel Kirkman, Daleen Koch, and the SWAIS 2C Science Team
Sci. Dril., 30, 101–112, https://doi.org/10.5194/sd-30-101-2022, https://doi.org/10.5194/sd-30-101-2022, 2022
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How much of the West Antarctic Ice Sheet will melt and how quickly it will happen when average global temperatures exceed 2 °C is currently unknown. Given the far-reaching and international consequences of Antarctica’s future contribution to global sea level rise, the SWAIS 2C Project was developed in order to better forecast the size and timing of future changes.
Nicolas Stoll, Maria Hörhold, Tobias Erhardt, Jan Eichler, Camilla Jensen, and Ilka Weikusat
The Cryosphere, 16, 667–688, https://doi.org/10.5194/tc-16-667-2022, https://doi.org/10.5194/tc-16-667-2022, 2022
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We mapped and analysed solid inclusion in the upper 1340 m of the EGRIP ice core with Raman spectroscopy and microstructure mapping, based on bulk dust content derived via continuous flow analysis. We observe a large variety in mineralogy throughout the core and samples. The main minerals are sulfates, especially gypsum, and terrestrial dust minerals, such as quartz, mica, and feldspar. A change in mineralogy occurs around 900 m depth indicating a climate-related imprint.
Steven Franke, Daniela Jansen, Tobias Binder, John D. Paden, Nils Dörr, Tamara A. Gerber, Heinrich Miller, Dorthe Dahl-Jensen, Veit Helm, Daniel Steinhage, Ilka Weikusat, Frank Wilhelms, and Olaf Eisen
Earth Syst. Sci. Data, 14, 763–779, https://doi.org/10.5194/essd-14-763-2022, https://doi.org/10.5194/essd-14-763-2022, 2022
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The Northeast Greenland Ice Stream (NEGIS) is the largest ice stream in Greenland. In order to better understand the past and future dynamics of the NEGIS, we present a high-resolution airborne radar data set (EGRIP-NOR-2018) for the onset region of the NEGIS. The survey area is centered at the location of the drill site of the East Greenland Ice-Core Project (EastGRIP), and radar profiles cover both shear margins and are aligned parallel to several flow lines.
Daniel Balting, Simon Michel, Viorica Nagavciuc, Gerhard Helle, Mandy Freund, Gerhard H. Schleser, David Steger, Gerrit Lohmann, and Monica Ionita
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-47, https://doi.org/10.5194/essd-2022-47, 2022
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Vapor pressure deficit is a key component of vegetation dynamics, soil science, meteorology, and soil science. In this study, we reconstruct the variability of the vapor pressure deficit in the past and examine the changes in future scenarios using climate models. In this way, past, present and future changes of the vapor pressure deficit can be detected locally, regionally, and continentally with higher statistical significance.
María H. Toyos, Gisela Winckler, Helge W. Arz, Lester Lembke-Jene, Carina B. Lange, Gerhard Kuhn, and Frank Lamy
Clim. Past, 18, 147–166, https://doi.org/10.5194/cp-18-147-2022, https://doi.org/10.5194/cp-18-147-2022, 2022
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Past export production in the southeast Pacific and its link to Patagonian ice dynamics is unknown. We reconstruct biological productivity changes at the Pacific entrance to the Drake Passage, covering the past 400 000 years. We show that glacial–interglacial variability in export production responds to glaciogenic Fe supply from Patagonia and silica availability due to shifts in oceanic fronts, whereas dust, as a source of lithogenic material, plays a minor role.
Arttu Jutila, Stefan Hendricks, Robert Ricker, Luisa von Albedyll, Thomas Krumpen, and Christian Haas
The Cryosphere, 16, 259–275, https://doi.org/10.5194/tc-16-259-2022, https://doi.org/10.5194/tc-16-259-2022, 2022
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Sea-ice thickness retrieval from satellite altimeters relies on assumed sea-ice density values because density cannot be measured from space. We derived bulk densities for different ice types using airborne laser, radar, and electromagnetic induction sounding measurements. Compared to previous studies, we found high bulk density values due to ice deformation and younger ice cover. Using sea-ice freeboard, we derived a sea-ice bulk density parameterisation that can be applied to satellite data.
Stephan Krätschmer, Michèlle van der Does, Frank Lamy, Gerrit Lohmann, Christoph Völker, and Martin Werner
Clim. Past, 18, 67–87, https://doi.org/10.5194/cp-18-67-2022, https://doi.org/10.5194/cp-18-67-2022, 2022
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We use an atmospheric model coupled to an aerosol model to investigate the global mineral dust cycle with a focus on the Southern Hemisphere for warmer and colder climate states and compare our results to observational data. Our findings suggest that Australia is the predominant source of dust deposited over Antarctica during the last glacial maximum. In addition, we find that the southward transport of dust from all sources to Antarctica happens at lower altitudes in colder climates.
Patrick Scholz, Dmitry Sidorenko, Sergey Danilov, Qiang Wang, Nikolay Koldunov, Dmitry Sein, and Thomas Jung
Geosci. Model Dev., 15, 335–363, https://doi.org/10.5194/gmd-15-335-2022, https://doi.org/10.5194/gmd-15-335-2022, 2022
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Structured-mesh ocean models are still the most mature in terms of functionality due to their long development history. However, unstructured-mesh ocean models have acquired new features and caught up in their functionality. This paper continues the work by Scholz et al. (2019) of documenting the features available in FESOM2.0. It focuses on the following two aspects: (i) partial bottom cells and embedded sea ice and (ii) dealing with mixing parameterisations enabled by using the CVMix package.
Timm Schultz, Ralf Müller, Dietmar Gross, and Angelika Humbert
The Cryosphere, 16, 143–158, https://doi.org/10.5194/tc-16-143-2022, https://doi.org/10.5194/tc-16-143-2022, 2022
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Firn is the interstage product between snow and ice. Simulations describing the process of firn densification are used in the context of estimating mass changes of the ice sheets and past climate reconstructions. The first stage of firn densification takes place in the upper few meters of the firn column. We investigate how well a material law describing the process of grain boundary sliding works for the numerical simulation of firn densification in this stage.
Nicolas Stoll, Jan Eichler, Maria Hörhold, Tobias Erhardt, Camilla Jensen, and Ilka Weikusat
The Cryosphere, 15, 5717–5737, https://doi.org/10.5194/tc-15-5717-2021, https://doi.org/10.5194/tc-15-5717-2021, 2021
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We did a systematic analysis of the location of inclusions in the EGRIP ice core, the first ice core from an ice stream. We combine this with crystal orientation and grain size data, enabling the first overview about the microstructure of this unique ice core. Micro-inclusions show a strong spatial variability and patterns (clusters or horizontal layers); roughly one-third is located at grain boundaries. More holistic approaches are needed to understand deformation processes in the ice better.
Martin Wegmann, Yvan Orsolini, Antje Weisheimer, Bart van den Hurk, and Gerrit Lohmann
Weather Clim. Dynam., 2, 1245–1261, https://doi.org/10.5194/wcd-2-1245-2021, https://doi.org/10.5194/wcd-2-1245-2021, 2021
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Northern Hemisphere winter weather is influenced by the strength of westerly winds 30 km above the surface, the so-called polar vortex. Eurasian autumn snow cover is thought to modulate the polar vortex. So far, however, the modeled influence of snow on the polar vortex did not fit the observed influence. By analyzing a model experiment for the time span of 110 years, we could show that the causality of this impact is indeed sound and snow cover can weaken the polar vortex.
Kim H. Stadelmaier, Patrick Ludwig, Pascal Bertran, Pierre Antoine, Xiaoxu Shi, Gerrit Lohmann, and Joaquim G. Pinto
Clim. Past, 17, 2559–2576, https://doi.org/10.5194/cp-17-2559-2021, https://doi.org/10.5194/cp-17-2559-2021, 2021
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We use regional climate simulations for the Last Glacial Maximum to reconstruct permafrost and to identify areas of thermal contraction cracking of the ground in western Europe. We find ground cracking, a precondition for the development of permafrost proxies, south of the probable permafrost border, implying that permafrost was not the limiting factor for proxy development. A good agreement with permafrost and climate proxy data is achieved when easterly winds are modelled more frequently.
Zixuan Han, Qiong Zhang, Qiang Li, Ran Feng, Alan M. Haywood, Julia C. Tindall, Stephen J. Hunter, Bette L. Otto-Bliesner, Esther C. Brady, Nan Rosenbloom, Zhongshi Zhang, Xiangyu Li, Chuncheng Guo, Kerim H. Nisancioglu, Christian Stepanek, Gerrit Lohmann, Linda E. Sohl, Mark A. Chandler, Ning Tan, Gilles Ramstein, Michiel L. J. Baatsen, Anna S. von der Heydt, Deepak Chandan, W. Richard Peltier, Charles J. R. Williams, Daniel J. Lunt, Jianbo Cheng, Qin Wen, and Natalie J. Burls
Clim. Past, 17, 2537–2558, https://doi.org/10.5194/cp-17-2537-2021, https://doi.org/10.5194/cp-17-2537-2021, 2021
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Understanding the potential processes responsible for large-scale hydrological cycle changes in a warmer climate is of great importance. Our study implies that an imbalance in interhemispheric atmospheric energy during the mid-Pliocene could have led to changes in the dynamic effect, offsetting the thermodynamic effect and, hence, altering mid-Pliocene hydroclimate cycling. Moreover, a robust westward shift in the Pacific Walker circulation can moisten the northern Indian Ocean.
Arthur M. Oldeman, Michiel L. J. Baatsen, Anna S. von der Heydt, Henk A. Dijkstra, Julia C. Tindall, Ayako Abe-Ouchi, Alice R. Booth, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Mark A. Chandler, Camille Contoux, Ran Feng, Chuncheng Guo, Alan M. Haywood, Stephen J. Hunter, Youichi Kamae, Qiang Li, Xiangyu Li, Gerrit Lohmann, Daniel J. Lunt, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Gabriel M. Pontes, Gilles Ramstein, Linda E. Sohl, Christian Stepanek, Ning Tan, Qiong Zhang, Zhongshi Zhang, Ilana Wainer, and Charles J. R. Williams
Clim. Past, 17, 2427–2450, https://doi.org/10.5194/cp-17-2427-2021, https://doi.org/10.5194/cp-17-2427-2021, 2021
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In this work, we have studied the behaviour of El Niño events in the mid-Pliocene, a period of around 3 million years ago, using a collection of 17 climate models. It is an interesting period to study, as it saw similar atmospheric carbon dioxide levels to the present day. We find that the El Niño events were less strong in the mid-Pliocene simulations, when compared to pre-industrial climate. Our results could help to interpret El Niño behaviour in future climate projections.
Cited articles
Ackermann, L., Danek, C., Gierz, P., and Lohmann, G.: AMOC recovery in a multicentennial scenario using a coupled atmosphere-ocean-ice Sheet model, Geophys. Res. Lett., 47, https://doi.org/10.1029/2019gl086810, 2020.
Ackermann, L., Rackow, T., Himstedt, K., Gierz, P., Knorr, G., and Lohmann, G.: A comprehensive Earth system model (AWI-ESM2.1) with interactive icebergs: effects on surface and deep-ocean characteristics, Geosci. Model Dev., 17, 3279–3301, https://doi.org/10.5194/gmd-17-3279-2024, 2024.
Arndt, S., Haas, C., Meyer, H., Peeken, I., and Krumpen, T.: Recent observations of superimposed ice and snow ice on sea ice in the northwestern Weddell Sea, The Cryosphere, 15, 4165–4178, https://doi.org/10.5194/tc-15-4165-2021, 2021.
Athanase, M., Sánchez-Benítez, A., Goessling, H. F., Pithan, F., and Jung, T.: Projected amplification of summer marine heatwaves in a warming northeast Pacific Ocean, Commun. Earth Environ., 5, https://doi.org/10.1038/s43247-024-01212-1, 2024a.
Athanase, M., Sánchez-Benítez, A., Monfort, E., Jung, T., and Goessling, H. F.: How climate change intensified storm boris' extreme rainfall, revealed by near-real-time storylines, Commun. Earth Environ., 5, https://doi.org/10.1038/s43247-024-01847-0, 2024b.
Balting, D. F., Ionita, M., Wegmann, M., Helle, G., Schleser, G. H., Rimbu, N., Freund, M. B., Heinrich, I., Caldarescu, D., and Lohmann, G.: Large-scale climate signals of a European oxygen isotope network from tree rings, Clim. Past, 17, 1005–1023, https://doi.org/10.5194/cp-17-1005-2021, 2021.
Barbi, D., Wieters, N., Gierz, P., Andrés-Martínez, M., Ural, D., Chegini, F., Khosravi, S., and Cristini, L.: ESM-Tools version 5.0: a modular infrastructure for stand-alone and coupled Earth system modelling (ESM), Geosci. Model Dev., 14, 4051–4067, https://doi.org/10.5194/gmd-14-4051-2021, 2021.
Bauer, P., Stevens, B., and Hazeleger, W.: A digital twin of Earth for the green transition, Nat. Clim. Change, 11, 80–83, https://doi.org/10.1038/s41558-021-00986-y, 2021.
Beech, N., Rackow, T., Semmler, T., Danilov, S., Wang, Q., and Jung, T.: Long-term evolution of Ocean Eddy activity in a warming world, Nat. Clim. Change, 12, 910–917, https://doi.org/10.1038/s41558-022-01478-3, 2022.
Bereiter, B., Eggleston, S., Schmitt, J., Nehrbass-Ahles, C., Stocker, T. F., Fischer, H., Kipfstuhl, S., and Chappellaz, J.: Revision of the EPICA Dome C CO2 record from 800 to 600 kyr before present, Geophys. Res. Lett., 42, 542–549, https://doi.org/10.1002/2014GL061957, 2015.
Bevacqua, E., Schleussner, C. F., and Zscheischler, J.: A year above 1.5 °C signals that Earth is most probably within the 20-year period that will reach the Paris Agreement limit, Nat. Clim. Change, https://doi.org/10.1038/s41558-025-02246-9, 2025.
Blanchet, C. L., Ramisch, A., Tjallingii, R., Ionita, M., Laruelle, L., Bagge, M., Klemann, V., and Brauer, A.: Climatic pacing of extreme nile floods during the North African humid period, Nat. Geosci., 17, 638–644, https://doi.org/10.1038/s41561-024-01471-9, 2024.
Butzin, M., Ye, Y., Völker, C., Gürses, Ö., Hauck, J., and Köhler, P.: Carbon isotopes in the marine biogeochemistry model FESOM2.1-REcoM3, Geosci. Model Dev., 17, 1709–1727, https://doi.org/10.5194/gmd-17-1709-2024, 2024.
Box, J. E., Yang, L., Bromwich, D. H., and Bai, L.: Greenland Ice Sheet surface air temperature variability: 1840–2007, J. Climate, 22, 4029–4049, https://doi.org/10.1175/2009JCLI2816.1, 2009.
Clark, P. U., Dyke, A. S., Shakun, J. D., Carlson, A. E., Clark, J., Wohlfarth, B., Mitrovica, J. X., Hostetler, S. W., and McCabe, A. M.: The Last Glacial Maximum, Science, 325, 710–714, https://doi.org/10.1126/science.1172873, 2009.
Contzen, J., Dickhaus, T., and Lohmann, G.: Variability and extremes: statistical validation of the Alfred Wegener Institute Earth System Model (AWI-ESM), Geosci. Model Dev., 15, 1803–1820, https://doi.org/10.5194/gmd-15-1803-2022, 2022.
DeConto, R. M. and Pollard, D.: Rapid Cenozoic glaciation of Antarctica induced by declining atmospheric CO2, Nature, 421, 245–249, https://doi.org/10.1038/nature01290, 2003.
Dima, M., Lohmann, G., Nichita, D.-R., Knorr, G. and Scholz, P.: Structural stability changes of the Atlantic Meridional Overturning Circulation, npj Clim. Atmos. Sci., 8, 73, https://doi.org/10.1038/s41612-025-00960-x, 2025.
Fahnestock, M., Abdalati, W., Joughin, I., Brozena, J., and Gogineni, P.: High geothermal heat flow, basal melt, and the origin of rapid ice flow in central Greenland, Science, 294, 2338–2342, https://doi.org/10.1126/science.1065370, 2001.
Flores, H., Veyssière, G., Castellani, G., Wilkinson, J., Hoppmann, M., Karcher, M., Valcic, L., Cornils, A., Geoffroy, M., Nicolaus, M., Niehoff, B., Priou, P., Schmidt, K., and Stroeve, J.: Sea-ice decline could keep zooplankton deeper for longer, Nat. Clim. Change, 13, 1122–1130, https://doi.org/10.1038/s41558-023-01779-1, 2023.
Franke, S., Bons, P. D., Westhoff, J., Weikusat, I., Binder, T., Streng, K., Steinhage, D., Helm, V., Eisen, O., Paden, J. D., Eagles, G., and Jansen, D.: Holocene ice-stream shutdown and drainage basin reconfiguration in Northeast Greenland, Nat. Geosci., 15, 995–1001, https://doi.org/10.1038/s41561-022-01082-2, 2022.
Fuchs, N., von Albedyll, L., Birnbaum, G., Linhardt, F., Oppelt, N., and Haas, C.: Sea ice melt pond bathymetry reconstructed from aerial photographs using photogrammetry: a new method applied to MOSAiC data, The Cryosphere, 18, 2991–3015, https://doi.org/10.5194/tc-18-2991-2024, 2024.
Geibert, W., Matthiessen, J., Stimac, I., Wollenburg, J., and Stein, R.: Glacial episodes of a Freshwater Arctic Ocean covered by a thick ice shelf, Nature, 590, 97–102, https://doi.org/10.1038/s41586-021-03186-y, 2021.
Geibert, W., Matthiessen, J., Wollenburg, J., and Stein, R.: Reply to: No freshwater-filled glacial Arctic Ocean, Nature, 602, https://doi.org/10.1038/s41586-021-04090-1, 2022.
Grosfeld, K., Treffeisen, R., Asseng, J., Bartsch, A., Bräuer, B., Fritzsch, B., Gerdes, R., Hendricks, S., Hiller, W., Heygster, G., Krumpen, T., Lemke, P., Melsheimer, C., Nicolaus, M., Ricker, R., and Weigelt, M.: Online sea-ice knowledge and data platform <http://www.meereisportal.de>, Polarforschung, 85, 143–155, https://doi.org/10.2312/polfor.2016.011, 2016.
Goessling, H. F., Rackow, T., and Jung, T.: Recent global temperature surge intensified by record-low planetary albedo, Science, 387, 68–73, https://doi.org/10.1126/science.adq7280, 2025.
Gohl, K., Uenzelmann-Neben, G., Gille-Petzoldt, J., Hillenbrand, C., Klages, J. P., Bohaty, S. M., Passchier, S., Frederichs, T., Wellner, J. S., Lamb, R., and Leitchenkov, G.: Evidence for a highly dynamic west antarctic ice sheet during the pliocene, Geophys. Res. Lett., 48, https://doi.org/10.1029/2021gl093103, 2021.
Gou, R., Lohmann, G., and Wu, L.: Atlantic Meridional Overturning Circulation Decline: Tipping small scales under global warming, Phys. Rev. Lett., 133, https://doi.org/10.1103/physrevlett.133.034201, 2024.
Gou, R., Wolf, K. K., Hoppe, C. J., Wu, L., and Lohmann, G.: The changing nature of future Arctic Marine Heatwaves and its potential impacts on the ecosystem, Nat. Clim. Change, 15, 162–170, https://doi.org/10.1038/s41558-024-02224-7, 2025.
Gowan, E. J., Zhang, X., Khosravi, S., Rovere, A., Stocchi, P., Hughes, A. L., Gyllencreutz, R., Mangerud, J., Svendsen, J.-I., and Lohmann, G.: A new global ice sheet reconstruction for the past 80000 years, Nat. Commun., 12, https://doi.org/10.1038/s41467-021-21469-w, 2021.
Haagmans, R. and Tsaoussi, L. (Eds.): Next Generation Gravity Mission as a Mass-change And Geosciences International Constellation (MAGIC) Mission Requirements Document, Earth and Mission Science Division, European Space Agency, NASA Earth Science Division, https://doi.org/10.5270/esa.nasa.magic-mrd.2020, 2020.
Hathorne, E., Dolman, A. M., and Laepple, T.: Assessing seasonal and inter-annual Marine Sediment Climate Proxy Data, Paleoceanography and Paleoclimatology, 38, https://doi.org/10.1029/2023pa004649, 2023.
Heukamp, F. O., Aue, L., Wang, Q., Ionita, M., Kanzow, T., Wekerle, C., and Rinke, A.: Cyclones modulate the control of the North Atlantic Oscillation on transports into the Barents Sea, Commun. Earth Environ., 4, https://doi.org/10.1038/s43247-023-00985-1, 2023.
Humbert, A., Helm, V., Neckel, N., Zeising, O., Rückamp, M., Khan, S. A., Loebel, E., Brauchle, J., Stebner, K., Gross, D., Sondershaus, R., and Müller, R.: Precursor of disintegration of Greenland's largest floating ice tongue, The Cryosphere, 17, 2851–2870, https://doi.org/10.5194/tc-17-2851-2023, 2023.
Hutter, N., Hendricks, S., Jutila, A., Ricker, R., von Albedyll, L., Birnbaum, G., and Haas, C.: Digital Elevation models of the sea-ice surface from airborne laser scanning during mosaic, Scientific Data, 10, https://doi.org/10.1038/s41597-023-02565-6, 2023.
Hébert, R., Herzschuh, U., and Laepple, T.: Millennial-scale climate variability over land overprinted by Ocean temperature fluctuations, Nat. Geosci., 15, 899–905, https://doi.org/10.1038/s41561-022-01056-4, 2022.
Hörhold, M., Münch, T., Weißbach, S., Kipfstuhl, S., Freitag, J., Sasgen, I., Lohmann, G., Vinther, B., and Laepple, T.: Modern temperatures in central–North Greenland warmest in past millennium, Nature, 613, 503–507, https://doi.org/10.1038/s41586-022-05517-z, 2023.
IPCC: Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Core Writing Team, Lee, H., and Romero, J., IPCC, Geneva, Switzerland, 35–115, https://doi.org/10.59327/IPCC/AR6-9789291691647, 2023.
Jansen, D., Franke, S., Bauer, C. C., Binder, T., Dahl-Jensen, D., Eichler, J., Eisen, O., Hu, Y., Kerch, J., Llorens, M.-G., Miller, H., Neckel, N., Paden, J., de Riese, T., Sachau, T., Stoll, N., Weikusat, I., Wilhelms, F., Zhang, Y., and Bons, P. D.: Shear margins in upper half of Northeast Greenland ice stream were established two millennia ago, Nat. Commun., 15, https://doi.org/10.1038/s41467-024-45021-8, 2024.
Jakobsson, M., Nilsson, J., O'Regan, M., Backman, J., Löwemark, L., Dowdeswell, J. A., Mayer, L., Polyak, L., Colleoni, F., Anderson, L. G., Björk, G., Cronin, T. M., Kirchner, N., Mohammad, R., Noormets, R., Nürnberg, D., Sellén, E., Stranne, C., Swärd, H., Greenwood, S. L., and Eriksson, B.: Evidence for an ice shelf covering the central Arctic Ocean during the penultimate glaciation, Nat. Commun., 7, 10365, https://doi.org/10.1038/ncomms10365, 2016.
John, A., Beyer, S., Athanase, M., Benítez, A. S., Goessling, H., Hossain, A., Nurisso, M., Aguridan, R., Andrés-Martínez, M., Gaya-Àvila, A., Cheedela, S. K., Geier, P., Ghosh, R., Hadade, I., Koldunov, N. V., Pedruzo-Bagazgoitia, X., Rackow, T., Sandu, I., Sidorenko, D., Streffing, J., Vitali, E., and Jung, T.: Global storyline simulations at the kilometre-scale, J. Adv. Model. Earth Sy., 18, e2025MS005326, https://doi.org/10.1029/2025MS005326, 2026.
Jonkers, L., Laepple, T., Rillo, M. C., Shi, X., Dolman, A. M., Lohmann, G., Paul, A., Mix, A., and Kucera, M.: Strong temperature gradients in the ice age North Atlantic Ocean revealed by Plankton Biogeography, Nat. Geosci., 16, 1114–1119, https://doi.org/10.1038/s41561-023-01328-7, 2023.
Joughin, I., Fahnestock, M., MacAyeal, D., Bamber, J. L., and Gogineni, P.: Observation and analysis of ice flow in the largest Greenland ice stream, J. Geophys. Res., 106, 34021–34034, https://doi.org/10.1029/2001JD900087, 2001.
Klages, J. P., Hillenbrand, C.-D., Bohaty, S. M., Salzmann, U., Bickert, T., Lohmann, G., Knahl, H. S., Gierz, P., Niu, L., Titschack, J., Kuhn, G., Frederichs, T., Müller, J., Bauersachs, T., Larter, R. D., Hochmuth, K., Ehrmann, W., Nehrke, G., Rodríguez-Tovar, F. J., Schmiedl, G., Spezzaferri, S., Läufer, A., Lisker, F., van de Flierdt, T., Eisenhauer, A., Uenzelmann-Neben, G., Esper, O., Smith, J. A., Pälike, H., Spiegel, C., Dziadek, R., Ronge, T. A., Freudenthal, T., and Gohl, K.: Ice sheet–free west antarctica during peak early oligocene glaciation, Science, 385, 322–327, https://doi.org/10.1126/science.adj3931, 2024.
Klages, J. P., Salzmann, U., Bickert, T., Hillenbrand, C.-D., Gohl, K., Kuhn, G., Bohaty, S. M., Titschack, J., Müller, J., Frederichs, T., Bauersachs, T., Ehrmann, W., van de Flierdt, T., Pereira, P. S., Larter, R. D., Lohmann, G., Niezgodzki, I., Uenzelmann-Neben, G., Zundel, M., Spiegel, C., Mark, C., Chew, D., Francis, J. E., Nehrke, G., Schwarz, F., Smith, J. A., Freudenthal, T., Esper, O., Pälike, H., Ronge, T. A., Dziadek, R., Afanasyeva, V., Arndt, J. E., Ebermann, B., Gebhardt, C., Hochmuth, K., Küssner, K., Najman, Y., Riefstahl, F., and Scheinert, M.: Temperate rainforests near the south pole during peak Cretaceous warmth, Nature, 580, 81–86, https://doi.org/10.1038/s41586-020-2148-5, 2020.
Knorr, G., Barker, S., Zhang, X., Lohmann, G., Gong, X., Gierz, P., Stepanek, C., and Stap, L. B.: A salty deep ocean as a prerequisite for glacial termination, Nat. Geosci., 14, 930–936, https://doi.org/10.1038/s41561-021-00857-3, 2021.
Knust, R.: Polar Research and Supply Vessel POLARSTERN operated by the Alfred-Wegener-Institute, J. Large-Scale Res. Facil., 3, A119, https://doi.org/10.17815/jlsrf-3-163, 2017.
Köhler, P., Nehrbass-Ahles, C., Schmitt, J., Stocker, T. F., and Fischer, H.: A 156 kyr smoothed history of the atmospheric greenhouse gases CO2, CH4, and N2O and their radiative forcing, Earth Syst. Sci. Data, 9, 363–387, https://doi.org/10.5194/essd-9-363-2017, 2017.
Köhler, P., Skinner, L. C., and Adolphi, F.: Radiocarbon cycle revisited by considering the bipolar seesaw and benthic 14C data, Earth Planet. Sc. Lett., 640, 118801, https://doi.org/10.1016/j.epsl.2024.118801, 2024.
Koldunov, N. and Jung, T.: Local climate services for all, courtesy of large language models, Commun. Earth Environ., 5, https://doi.org/10.1038/s43247-023-01199-1, 2024.
Koldunov, N. V., Aizinger, V., Rakowsky, N., Scholz, P., Sidorenko, D., Danilov, S., and Jung, T.: Scalability and some optimization of the Finite-volumE Sea ice–Ocean Model, Version 2.0 (FESOM2), Geosci. Model Dev., 12, 3991–4012, https://doi.org/10.5194/gmd-12-3991-2019, 2019.
Kreibich, H., Schröter, K., Di Baldassarre, G., Van Loon, A. F., Mazzoleni, M., Abeshu, G. W., Agafonova, S., AghaKouchak, A., Aksoy, H., Alvarez-Garreton, C., Aznar, B., Balkhi, L., Barendrecht, M. H., Biancamaria, S., Bos-Burgering, L., Bradley, C., Budiyono, Y., Buytaert, W., Capewell, L., Carlson, H., Cavus, Y., Couasnon, A., Coxon, G., Daliakopoulos, I., de Ruiter, M. C., Delus, C., Erfurt, M., Esposito, G., François, D., Frappart, F., Freer, J., Frolova, N., Gain, A. K., Grillakis, M., Grima, J. O., Guzmán, D. A., Huning, L. S., Ionita, M., Kharlamov, M., Khoi, D. N., Kieboom, N., Kireeva, M., Koutroulis, A., Lavado-Casimiro, W., Li, H.-Y., LLasat, M. C., Macdonald, D., Mård, J., Mathew-Richards, H., McKenzie, A., Mejia, A., Mendiondo, E. M., Mens, M., Mobini, S., Mohor, G. S., Nagavciuc, V., Ngo-Duc, T., Nguyen, H. T. T., Nhi, P. T. T., Petrucci, O., Quan, N. H., Quintana-Seguí, P., Razavi, S., Ridolfi, E., Riegel, J., Sadik, M. S., Sairam, N., Savelli, E., Sazonov, A., Sharma, S., Sörensen, J., Souza, F. A. A., Stahl, K., Steinhausen, M., Stoelzle, M., Szalińska, W., Tang, Q., Tian, F., Tokarczyk, T., Tovar, C., Tran, T. V. T., van Huijgevoort, M. H. J., van Vliet, M. T. H., Vorogushyn, S., Wagener, T., Wang, Y., Wendt, D. E., Wickham, E., Yang, L., Zambrano-Bigiarini, M., and Ward, P. J.: Panta Rhei benchmark dataset: socio-hydrological data of paired events of floods and droughts, Earth Syst. Sci. Data, 15, 2009–2023, https://doi.org/10.5194/essd-15-2009-2023, 2023.
Krumpen, T., von Albedyll, L., Bünger, H. J., Castellani, G., Hartmann, J., Helm, V., Hendricks, S., Hutter, N., Landy, J. C., Lisovski, S., Lüpkes, C., Rohde, J., Suhrhoff, M., and Haas, C.: Smoother sea ice with fewer pressure ridges in a more dynamic Arctic, Nat. Clim. Change, 15, 66–72, https://doi.org/10.1038/s41558-024-02199-5, 2025.
Laepple, T., Ziegler, E., Weitzel, N., Hébert, R., Ellerhoff, B., Schoch, P., Martrat, B., Bothe, O., Moreno-Chamarro, E., Chevalier, M., Herbert, A., and Rehfeld, K.: Regional but not global temperature variability underestimated by climate models at Supradecadal Timescales, Nat. Geosci., 16, 958–966, https://doi.org/10.1038/s41561-023-01299-9, 2023.
Lambeck, K., Rouby, H., Purcell, A., Sun, Y. and Sambridge, M.: Sea level and global ice volumes from the Last Glacial Maximum to the Holocene, P. Natl. Acad. Sci. USA, 111, 15296–15303, https://doi.org/10.1073/pnas.1411762111, 2014.
Lamy, F., Winckler, G., Arz, H. W., Farmer, J. R., Gottschalk, J., Lembke-Jene, L., Middleton, J. L., van der Does, M., Tiedemann, R., Alvarez Zarikian, C., Basak, C., Brombacher, A., Dumm, L., Esper, O. M., Herbert, L. C., Iwasaki, S., Kreps, G., Lawson, V. J., Lo, L., Malinverno, E., Martinez-Garcia, A., Michel, E., Moretti, S., Moy, C. M., Ravelo, A. C., Riesselman, C. R., Saavedra-Pellitero, M., Sadatzki, H., Seo, I., Singh, R. K., Smith, R. A., Souza, A. L., Stoner, J. S., Toyos, M., de Oliveira, I. M., Wan, S., Wu, S., and Zhao, X.: Five Million Years of Antarctic circumpolar current strength variability, Nature, 627, 789–796, https://doi.org/10.1038/s41586-024-07143-3, 2024.
Li, X., Wang, Q., Danilov, S., Koldunov, N., Liu, C., Müller, V., Sidorenko, D., and Jung, T.: Eddy activity in the Arctic Ocean projected to surge in a warming world, Nat. Clim. Change, 14, 156–162, https://doi.org/10.1038/s41558-023-01908-w, 2024.
Lohmann, G.: Conversations on Climate: The People Behind the Science. SpringerBriefs in Climate Studies, Springer, Cham, 118 pp., ISBN 978-3-032-19147-2, https://doi.org/10.1007/978-3-032-19147-2, 2026.
Lohmann, G., Butzin, M., Eissner, N., Shi, X., and Stepanek, C: Abrupt climate and weather changes across timescales, Paleoceanography and Paleoclimatology, 35, e2019PA003782, https://doi.org/10.1029/2019PA003782, 2020.
Ma, Q., Shi, X., Scholz, P., Sidorenko, D., Lohmann, G., and Ionita, M.: Revisiting climate impacts of an AMOC slowdown: Dependence on freshwater locations in the North Atlantic, Science Advances, 10, https://doi.org/10.1126/sciadv.adr3243, 2024.
Marshall, J. and Speer, K.: Closure of the meridional overturning circulation through Southern Ocean upwelling. Nat. Geosci., 5, 171–180, https://doi.org/10.1038/ngeo1391, 2012.
Martin, T., Biastoch, A., Lohmann, G., Mikolajewicz, U., and Wang, X.: On timescales and reversibility of the ocean's response to enhanced Greenland Ice Sheet Melting in comprehensive climate models, Geophys. Res. Lett., 49, https://doi.org/10.1029/2021gl097114, 2022.
Masoum, A., Nerger, L., Willeit, M., Ganopolski, A., and Lohmann, G.: Paleoclimate data assimilation with climber-X: An ensemble Kalman filter for the last deglaciation, PLOS ONE, 19, https://doi.org/10.1371/journal.pone.0300138, 2024.
McPherson, R. A., Wekerle, C., and Kanzow, T.: Shifts of the recirculation pathways in Central Fram Strait Drive Atlantic Intermediate Water Variability on northeast Greenland shelf, J. Geophys. Res.-Oceans, 128, https://doi.org/10.1029/2023jc019915, 2023.
McPherson, R. A., Wekerle, C., Kanzow, T., Ionita, M., Heukamp, F. O., Zeising, O., and Humbert, A.: Atmospheric blocking slows ocean-driven melting of Greenland's largest glacier tongue, Science, 385, 1360–1366, https://doi.org/10.1126/science.ado5008, 2024.
Meinshausen, M., Nicholls, Z. R. J., Lewis, J., Gidden, M. J., Vogel, E., Freund, M., Beyerle, U., Gessner, C., Nauels, A., Bauer, N., Canadell, J. G., Daniel, J. S., John, A., Krummel, P. B., Luderer, G., Meinshausen, N., Montzka, S. A., Rayner, P. J., Reimann, S., Smith, S. J., van den Berg, M., Velders, G. J. M., Vollmer, M. K., and Wang, R. H. J.: The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500, Geosci. Model Dev., 13, 3571–3605, https://doi.org/10.5194/gmd-13-3571-2020, 2020.
Morganti, T. M., Slaby, B. M., de Kluijver, A., Busch, K., Hentschel, U., Middelburg, J. J., Grotheer, H., Mollenhauer, G., Dannheim, J., Rapp, H. T., Purser, A., and Boetius, A.: Giant sponge grounds of central Arctic seamounts are associated with extinct seep life, Nat. Commun., 13, https://doi.org/10.1038/s41467-022-28129-7, 2022.
Nagavciuc, V., Michel, S. L. L., Balting, D. F., Helle, G., Freund, M., Schleser, G. H., Steger, D. N., Lohmann, G., and Ionita, M.: A past and present perspective on the European summer vapor pressure deficit, Clim. Past, 20, 573–595, https://doi.org/10.5194/cp-20-573-2024, 2024.
Neckel, N., Fuchs, N., Birnbaum, G., Hutter, N., Jutila, A., Buth, L., von Albedyll, L., Ricker, R., and Haas, C.: Helicopter-borne RGB orthomosaics and photogrammetric digital elevation models from the MOSAiC Expedition, Sci. Data, 10, 426, https://doi.org/10.1038/s41597-023-02318-5, 2023.
Nicolas, A., Mollenhauer, G., Lachner, J., Stübner, K., Malter, M., Wollenburg, J., Grotheer, H., and Adolphi, F.: Precise dating of deglacial Laptev Sea sediments via 14C and authigenic 10Be
Nissen, C., Timmermann, R., Hoppema, M., Gürses, Ö., and Hauck, J.: Abruptly attenuated carbon sequestration with Weddell Sea dense waters by 2100, Nat. Commun., 13, https://doi.org/10.1038/s41467-022-30671-3, 2022.
Niu, L., Knorr, G., Krebs-Kanzow, U., Gierz, P., and Lohmann, G.: Rapid Laurentide ice sheet growth preceding the last Glacial Maximum due to summer snowfall, Nat. Geosci., 17, 440–449, https://doi.org/10.1038/s41561-024-01419-z, 2024.
Pithan, F., Athanase, M., Dahlke, S., Sánchez-Benítez, A., Shupe, M. D., Sledd, A., Streffing, J., Svensson, G., and Jung, T.: Nudging allows direct evaluation of coupled climate models with in situ observations: a case study from the MOSAiC expedition, Geosci. Model Dev., 16, 1857–1873, https://doi.org/10.5194/gmd-16-1857-2023, 2023.
Rabe, B., Cox, C. J., Fang, Y.-C., Goessling, H., Granskog, M. A., Hoppmann, M., Hutchings, J. K., Krumpen, T., Kuznetsov, I., Lei, R., Li, T., Maslowski, W., Nicolaus, M., Perovich, D., Persson, O., Regnery, J., Rigor, I., Shupe, M. D., Sokolov, V., Spreen, G., Stanton, T., Watkins, D. M., Blockley, E., Buenger, H. J., Cole, S., Fong, A., Haapala, J., Heuzé, C., Hoppe, C. J., Janout, M., Jutila, A., Katlein, C., Krishfield, R., Lin, L., Ludwig, V., Morgenstern, A., O'Brien, J., Zurita, A. Q., Rackow, T., Riemann-Campe, K., Rohde, J., Shaw, W., Smolyanitsky, V., Solomon, A., Sperling, A., Tao, R., Toole, J., Tsamados, M., Zhu, J., and Zuo, G.: The mosaic distributed network: Observing the coupled arctic system with multidisciplinary, coordinated platforms, Elem. Sci. Anth., 12, https://doi.org/10.1525/elementa.2023.00103, 2024.
Rackow, T., Danilov, S., Goessling, H. F., Hellmer, H. H., Sein, D. V., Semmler, T., Sidorenko, D., and Jung, T.: Delayed antarctic sea-ice decline in high-resolution climate change simulations, Nat. Commun., 13, https://doi.org/10.1038/s41467-022-28259-y, 2022.
Rantanen, M., Karpechko, A. Y., Lipponen, A., Nordling, K., Hyvärinen, O., Ruosteenoja, K., Vihma, T., and Laaksonen, A.: The Arctic has warmed nearly four times faster than the globe since 1979, Commun. Earth Environ., 3, 168, https://doi.org/10.1038/s43247-022-00498-3, 2022.
Ricker, R., Kauker, F., Schweiger, A., Hendricks, S., Zhang, J., and Paul, S.: Evidence for an increasing role of ocean heat in Arctic Winter Sea ice growth, J. Climate, 1–42, https://doi.org/10.1175/jcli-d-20-0848.1, 2021.
Rimbu, N., Spiegl, T., Ionita, M., Doshi, S., and Lohmann, G.: A synoptic scale perspective of solar forcing on extreme precipitation and floods over Europe during summer, J. Geophys. Res.-Atmos., 129, https://doi.org/10.1029/2024jd041952, 2024.
Rintoul, S. R., Hughes, C. W., and Olbers, D.: The Antarctic Circumpolar Current system. In: Ocean Circulation and Climate, International Geophysics Series, Vol. 77, Academic Press, 271–302, https://doi.org/10.1016/S0074-6142(01)80124-8, 2001.
Ruben, M., Hefter, J., Schubotz, F., Geibert, W., Butzin, M., Gentz, T., Grotheer, H., Forwick, M., Szczuciński, W., and Mollenhauer, G.: Fossil Organic Carbon Utilization in Marine Arctic Fjord sediments by subsurface micro-organisms, Nat. Geosci., 16, 625–630, https://doi.org/10.1038/s41561-023-01198-z, 2023.
Ruben, M., Marchant, H., Wietz, M., Gentz, T., Strauss, J., Koch, B. P., and Mollenhauer, G.: Microbial communities degrade ancient permafrost-derived organic matter in Arctic seawater, J. Geophys. Res.-Biogeo., 129, https://doi.org/10.1029/2023jg007936, 2024.
Purich, A. and Doddridge, E. W.: Record low Antarctic sea ice coverage indicates a new sea ice state, Commun. Earth Environ., 4, 314, https://doi.org/10.1038/s43247-023-00961-9, 2023.
Sánchez-Benítez, A., Goessling, H., Pithan, F., Semmler, T., and Jung, T.: The July 2019 european heat wave in a warmer climate: Storyline scenarios with a coupled model using spectral nudging, J. Climate, 35, 2373–2390, https://doi.org/10.1175/jcli-d-21-0573.1, 2022.
Sasgen, I., Wouters, B., Gardner, A. S., King, M. D., Tedesco, M., Landerer, F. W., Dahle, C., Save, H., and Fettweis, X.: Return to rapid ice loss in Greenland and record loss in 2019 detected by the Grace-FO satellites, Commun. Earth Environ., 1, https://doi.org/10.1038/s43247-020-0010-1, 2020.
Sasgen, I., Salles, A., Wegmann, M., Wouters, B., Fettweis, X., Noël, B. P., and Beck, C.: Arctic Glaciers record Wavier Circumpolar Winds, Nat. Clim. Change, 12, 249–255, https://doi.org/10.1038/s41558-021-01275-4, 2022.
Schachtschneider, R., Saynisch-Wagner, J., Sánchez-Benítez, A., and Thomas, M.: Neural network based estimates of the climate impact on mortality in Germany: Application to storyline Climate simulations, Sci. Rep., 14, https://doi.org/10.1038/s41598-024-77398-3, 2024.
Schaffer, J., Kanzow, T., von Appen, W.-J., von Albedyll, L., Arndt, J. E., and Roberts, D. H.: Bathymetry constrains ocean heat supply to Greenland’s largest glacier tongue, Nat. Geosci., 13, 227–231, https://doi.org/10.1038/s41561-019-0529-x, 2020.
Scholz, P., Sidorenko, D., Danilov, S., Wang, Q., Koldunov, N., Sein, D., and Jung, T.: Assessment of the Finite-VolumE Sea ice–Ocean Model (FESOM2.0) – Part 2: Partial bottom cells, embedded sea ice and vertical mixing library CVMix, Geosci. Model Dev., 15, 335–363, https://doi.org/10.5194/gmd-15-335-2022, 2022.
Semmler, T., Danilov, S., Rackow, T., Sidorenko, D., Wang, Q., and Jung, T.: Simulations for CMIP6 with the AWI Climate Model AWI-CM-1-1, J. Adv. Model. Earth Sy., 12, e2019MS002009, https://doi.org/10.1029/2019MS002009, 2020.
Silvano, A., Narayanan, A., Catany, R., Olmedo, E., González-Gambau, V., Turiel, A., Sabia, R., Mazloff, M. R., Spira, T., Haumann, F. A., and Naveira Garabato, A. C.: Rising surface salinity and declining sea ice: A new Southern Ocean state revealed by satellites, P. Natl. Acad. Sci. USA, 122, e2500440122, https://doi.org/10.1073/pnas.2500440122, 2025.
Song, P., Sidorenko, D., Scholz, P., Thomas, M., and Lohmann, G.: The tidal effects in the Finite-volumE Sea ice–Ocean Model (FESOM2.1): a comparison between parameterised tidal mixing and explicit tidal forcing, Geosci. Model Dev., 16, 383–405, https://doi.org/10.5194/gmd-16-383-2023, 2023.
Spielhagen, R. F., Scholten, J. C., Bauch, H. A., and Eisenhauer, A.: No freshwater-filled glacial Arctic Ocean, Nature, 602, https://doi.org/10.1038/s41586-021-04089-8, 2022.
Steiner, L., Schmithüsen, H., Wickert, J., and Eisen, O.: Combined GNSS reflectometry–refractometry for automated and continuous in situ surface mass balance estimation on an Antarctic ice shelf, The Cryosphere, 17, 4903–4916, https://doi.org/10.5194/tc-17-4903-2023, 2023.
Straneo, F. and Heimbach, P.: North Atlantic warming and the retreat of Greenland's outlet glaciers, Nature, 504, 36–43, https://doi.org/10.1038/nature12854, 2013.
Streffing, J., Sidorenko, D., Semmler, T., Zampieri, L., Scholz, P., Andrés-Martínez, M., Koldunov, N., Rackow, T., Kjellsson, J., Goessling, H., Athanase, M., Wang, Q., Hegewald, J., Sein, D. V., Mu, L., Fladrich, U., Barbi, D., Gierz, P., Danilov, S., Juricke, S., Lohmann, G., and Jung, T.: AWI-CM3 coupled climate model: description and evaluation experiments for a prototype post-CMIP6 model, Geosci. Model Dev., 15, 6399–6427, https://doi.org/10.5194/gmd-15-6399-2022, 2022.
Tao, R., Nicolaus, M., Katlein, C., Anhaus, P., Hoppmann, M., Spreen, G., Niehaus, H., Jäkel, E., Wendisch, M., and Haas, C.: Seasonality of spectral radiative fluxes and optical properties of Arctic sea ice during the Spring–Summer Transition, Elem. Sci. Anth., 12, https://doi.org/10.1525/elementa.2023.00130, 2024.
The CenCO2PIP Consortium: Toward a Cenozoic history of atmospheric CO2, Science, 382, eadi5177, https://doi.org/10.1126/science.adi5177, 2023.
von Albedyll, L., Hendricks, S., Grodofzig, R., Krumpen, T., Arndt, S., Belter, H. J., Birnbaum, G., Cheng, B., Hoppmann, M., Hutchings, J., Itkin, P., Lei, R., Nicolaus, M., Ricker, R., Rohde, J., Suhrhoff, M., Timofeeva, A., Watkins, D., Webster, M. and Haas, C.: Thermodynamic and dynamic contributions to seasonal Arctic sea ice thickness distributions from airborne observations, Elem. Sci. Anth., 10, https://doi.org/10.1525/elementa.2021.00074, 2022.
von Albedyll, L., Hendricks, S., Hutter, N., Murashkin, D., Kaleschke, L., Willmes, S., Thielke, L., Tian-Kunze, X., Spreen, G., and Haas, C.: Lead fractions from SAR-derived sea ice divergence during MOSAiC, The Cryosphere, 18, 1259–1285, https://doi.org/10.5194/tc-18-1259-2024, 2024.
von Appen, W.-J., Waite, A. M., Bergmann, M., Bienhold, C., Boebel, O., Bracher, A., Cisewski, B., Hagemann, J., Hoppema, M., Iversen, M. H., Konrad, C., Krumpen, T., Lochthofen, N., Metfies, K., Niehoff, B., Nöthig, E.-M., Purser, A., Salter, I., Schaber, M., Scholz, D., Soltwedel, T., Torres-Valdes, S., Wekerle, C., Wenzhöfer, F., Wietz, M., and Boetius, A.: Sea-ice derived meltwater stratification slows the biological carbon pump: Results from Continuous Observations, Nat. Commun., 12, https://doi.org/10.1038/s41467-021-26943-z, 2021.
Wekerle, C., McPherson, R., von Appen, W.-J., Wang, Q., Timmermann, R., Scholz, P., Danilov, S., Shu, Q., and Kanzow, T.: Atlantic water warming increases melt below Northeast Greenland's last Floating ice tongue, Nat. Commun., 15, https://doi.org/10.1038/s41467-024-45650-z, 2024.
Wirtz, K. W., Antunes, N., Diachenko, A., Laabs, J., Lemmen, C., Lohmann, G., McLaughlin, R., Zorita, E., and Gronenborn, D.: Multicentennial Cycles in continental demography synchronous with solar activity and climate stability, Nat. Commun., 15, https://doi.org/10.1038/s41467-024-54474-w, 2024.
Wollenburg, J. E., Matthiessen, J., Vogt, C., Nehrke, G., Grotheer, H., Wilhelms-Dick, D., Geibert, W., and Mollenhauer, G.: Omnipresent authigenic calcite distorts arctic radiocarbon chronology, Commun. Earth Environ., 4, https://doi.org/10.1038/s43247-023-00802-9, 2023.
Wu, J., Mollenhauer, G., Stein, R., Köhler, P., Hefter, J., Fahl, K., Grotheer, H., Wei, B., and Nam, S.-I.: Deglacial release of Petrogenic and permafrost carbon from the Canadian arctic impacting the carbon cycle, Nat. Commun., 13, https://doi.org/10.1038/s41467-022-34725-4, 2022.
Wu, S., Lembke-Jene, L., Lamy, F., Arz, H. W., Nowaczyk, N., Xiao, W., Zhang, X., Hass, H. C., Titschack, J., Zheng, X., Liu, J., Dumm, L., Diekmann, B., Nürnberg, D., Tiedemann, R., and Kuhn, G.: Orbital- and millennial-scale Antarctic circumpolar current variability in Drake Passage over the past 140,000 years, Nat. Commun., 12, https://doi.org/10.1038/s41467-021-24264-9, 2021.
Xu, R., Zhao, C., Arndt, S., and Haas, C.: Dual-frequency radar observations of snowmelt processes on Antarctic perennial sea ice by CFOSCAT and ASCAT, The Cryosphere, 18, 5769–5788, https://doi.org/10.5194/tc-18-5769-2024, 2024.
Yang, H.: Warming hotspots induced by more eddies, Nat. Clim. Change, 12, 889–890, https://doi.org/10.1038/s41558-022-01488-1, 2022.
Yang, H., Lohmann, G., Lu, J., Gowan, E. J., Shi, X., Liu, J., and Wang, Q.: Tropical expansion driven by poleward advancing midlatitude meridional temperature gradients, J. Geophys. Res., Atmos., 125, https://doi.org/10.1029/2020jd033158, 2020.
Yang, H., Lohmann, G., Stepanek, C., Wang, Q., Huang, R. X., Shi, X., Liu, J., Chen, D., Wang, X., Zhong, Y., Yang, Q., Bao, Y., and Müller, J.: Satellite-observed strong subtropical ocean warming as an early signature of global warming, Commun. Earth Environ., 4, https://doi.org/10.1038/s43247-023-00839-w, 2023.
Ye, Y., Munhoven, G., Köhler, P., Butzin, M., Hauck, J., Gürses, Ö., and Völker, C.: FESOM2.1-REcoM3-MEDUSA2: an ocean–sea ice–biogeochemistry model coupled to a sediment model, Geosci. Model Dev., 18, 977–1000, https://doi.org/10.5194/gmd-18-977-2025, 2025.
Zachos, J. C., Dickens, G. R., and Zeebe, R. E.: An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics, Nature, 451, 279–283, https://doi.org/10.1038/nature06588, 2008.
Zeising, O., Neckel, N., Dörr, N., Helm, V., Steinhage, D., Timmermann, R., and Humbert, A.: Extreme melting at Greenland's largest floating ice tongue, The Cryosphere, 18, 1333–1357, https://doi.org/10.5194/tc-18-1333-2024, 2024.
Short summary
This paper reviews how the Alfred Wegener Institute studies changes in the ocean and the polar ice regions under climate warming. We bring together results from field observations, laboratory work, and computer models to show how melting ice and changing seas affect global climate and sea level. By combining many approaches, we identify key advances, remaining gaps, and future priorities. Integrating these methods improves our ability to project future climate change and guide decision-making.
This paper reviews how the Alfred Wegener Institute studies changes in the ocean and the polar...
