Articles | Volume 18, issue 12
https://doi.org/10.5194/tc-18-5641-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-18-5641-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Brief communication
| 
05 Dec 2024
Brief communication |
| 05 Dec 2024
| 05 Dec 2024
Brief communication: New perspectives on the skill of modelled sea ice trends in light of recent Antarctic sea ice loss
British Antarctic Survey, Cambridge, CB3 0ET, UK
Thomas J. Bracegirdle
British Antarctic Survey, Cambridge, CB3 0ET, UK
Paul R. Holland
British Antarctic Survey, Cambridge, CB3 0ET, UK
Julienne Stroeve
National Snow and Ice Data Center, Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA
Centre for Earth Observation Science, University of Manitoba, Winnipeg, Manitoba, Canada
Earth Sciences, University College London, London, UK
Jeremy Wilkinson
British Antarctic Survey, Cambridge, CB3 0ET, UK
Related authors
No articles found.
Anton Komarov and Julienne Stroeve
EGUsphere, https://doi.org/10.5194/egusphere-2026-3873, https://doi.org/10.5194/egusphere-2026-3873, 2026
This preprint is open for discussion and under review for Hydrology and Earth System Sciences (HESS).
Short summary
Short summary
Warming climate and changing precipitation regimes in Arctic and boreal regions cause frequent rain-on-snow events when liquid water precipitate on the snow surface leading to water infiltration, heterogeneous flow, and the development of refrozen percolation features within the snowpack. These processes change the physical properties of the snow and may lead to liquid-water runoff. In this paper, we investigate how local factors affect these processes in a taiga environment.
Julienne Stroeve, Rosemary Willatt, Madeleine Downie, Monojit Saha, Carmen Nab, Alicia Fallows, Clement Soriot, Robbie Mallett, Anton Komarov, Vishnu Nandan, Thomas Newman, Jennifer Lukovich, and John Yackel
The Cryosphere, 20, 4367–4399, https://doi.org/10.5194/tc-20-4367-2026, https://doi.org/10.5194/tc-20-4367-2026, 2026
Short summary
Short summary
We evaluate polarimetry for snow depth retrieval on Arctic winter transport routes. Over landfast ice and tundra, traditional dual-frequency (Ku/Ka) methods often fail. We demonstrate that cross-polarization (VH) provides a more reliable marker for snow/ice and snow/ground interfaces. For lakes, we successfully resolve air, snow, and ice interfaces to retrieve snow and ice thickness simultaneously. These results establish a baseline for future polarimetric satellite missions.
Yvonne Anderson, Amanda C. Maycock, Juliane Schwendike, Thomas J. Bracegirdle, Simon A. Josey, and Doug M. Smith
EGUsphere, https://doi.org/10.5194/egusphere-2026-4140, https://doi.org/10.5194/egusphere-2026-4140, 2026
This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
Short summary
Short summary
This study assessed how well climate models represent relationships between the North Atlantic ocean and atmosphere in autumn and winter. While models simulate observed relationships in autumn and winter, they fail to capture them in the transition between seasons. The results suggest the link between autumn sea surface temperatures and the winter atmosphere is driven mainly by atmospheric rather than ocean processes, highlighting important model biases that may limit seasonal forecast skill.
Daniel N. Goldberg, Paul R. Holland, and Kaitlin A. Naughten
EGUsphere, https://doi.org/10.5194/egusphere-2026-3779, https://doi.org/10.5194/egusphere-2026-3779, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Antarctica’s Amundsen Sea glaciers are major contributors to sea-level rise. Using multi-century, high-resolution coupled ice–ocean simulations of the region, we show that 21st century predictions depend strongly on how ice-sheet models are initialized, especially for Thwaites Glacier. By the 22nd century, however, ocean warming becomes the dominant driver, leading to much faster ice loss under high-emissions scenarios, highlighting the importance of improving coupled climate–ice models.
Alexander T. Bradley, David T. Bett, C. Rosie Williams, Robert J. Arthern, Paul R. Holland, James Byrne, Tamsin L. Edwards, and Mira Adhikari
The Cryosphere, 20, 3443–3465, https://doi.org/10.5194/tc-20-3443-2026, https://doi.org/10.5194/tc-20-3443-2026, 2026
Short summary
Short summary
At least since we began measuring in detail, the West Antarctic Ice Sheet has lost a lot of ice, but we don't know precisely how important climate change is in this. Here, we put a number on the role of climate change in retreat of a glacier in this ice sheet, for the first time. We show that climate change made the shrinking of this glacier much worse. Our work also suggests that what happened on very long timescales (the last 10,000 years) might also matter for retreat of the ice sheets today.
Anna Olivé Abelló, Pierre Mathiot, Nicolas C. Jourdain, Yavor Kostov, and Paul R. Holland
EGUsphere, https://doi.org/10.5194/egusphere-2026-3422, https://doi.org/10.5194/egusphere-2026-3422, 2026
This preprint is open for discussion and under review for Ocean Science (OS).
Short summary
Short summary
Antarctic icebergs release large amounts of freshwater, but models often add it entirely at the ocean surface. Using simulations with drifting icebergs, we assessed whether releasing meltwater at depth alters the Southern Ocean's response. Most meltwater remained in the surface mixed layer, and deeper release caused only weak, local changes in the ocean, sea ice and ice shelf melting. Hence, surface release remains a reasonable approach for large-scale studies, though depth matters regionally.
Luisa E. Avilés-Podgurski, Patrick Martineau, Hua Lu, Ayako Yamamoto, Amanda C. Maycock, Andrew Orr, Tony Phillips, Thomas J. Bracegirdle, Anna E. Hogg, Grzegorz Muszynski, and Andrew Fleming
Weather Clim. Dynam., 7, 1051–1071, https://doi.org/10.5194/wcd-7-1051-2026, https://doi.org/10.5194/wcd-7-1051-2026, 2026
Short summary
Short summary
Atmospheric rivers (ARs) are narrow filaments of intense poleward water vapour transport. On rare occasions, they reach the Arctic, driving strong warming and melt. In April 2020, two ARs intruded into the central Arctic within one week, raising near-surface temperatures by up to 30°C and leading to extreme precipitation. Their distinct paths and thermodynamic evolution reveal diverse AR impacts on Arctic sea ice and precipitation extremes.
Paul Holland, Adrian Jenkins, David Bett, and Suzanne Bevan
EGUsphere, https://doi.org/10.5194/egusphere-2026-2835, https://doi.org/10.5194/egusphere-2026-2835, 2026
Short summary
Short summary
Ice loss from the Amundsen Sea sector of the Antarctic Ice Sheet is a major contributor to global sea-level rise. In this study we use ocean simulations to understand the ice melting in this sector. The strongest melting is focussed on deep ice where the glaciers flow into the ocean. Secondary areas of melting occur beneath meltwater currents. The simulations are used to test simple mathematical representations of melting that could be built into an ice sheet model.
Lanqing Huang, Julienne Stroeve, Thomas Newman, Robbie Mallett, Rosemary Willatt, Lu Zhou, Malin Johansson, Carmen Nab, and Alicia Fallows
The Cryosphere, 20, 2825–2849, https://doi.org/10.5194/tc-20-2825-2026, https://doi.org/10.5194/tc-20-2825-2026, 2026
Short summary
Short summary
Understanding snow depth on sea ice is key for measuring ice thickness, studying ecosystems, and modelling climate. Using snow and ice thickness measurements from Arctic and Antarctic campaigns, this study examines sub-kilometre-scale (<1 km²) snow depth variations and identifies the most suitable statistical models for different ice ages, thicknesses, and weather conditions. These results can improve sub-grid snow parameterisations in snow models and remote sensing algorithms.
Robin S. Smith, Tarkan A. Bilge, Thomas J. Bracegirdle, Paul R. Holland, Till Kuhlbrodt, Charlotte Lang, Spencer Liddicoat, Tom Mitcham, Jane Mulcahy, Kaitlin A. Naughten, Andrew Orr, Julien Palmieri, Antony J. Payne, Steven Rumbold, Marc Stringer, Ranjini Swaminathan, Sarah Taylor, Jeremy Walton, and Colin Jones
Earth Syst. Dynam., 17, 475–493, https://doi.org/10.5194/esd-17-475-2026, https://doi.org/10.5194/esd-17-475-2026, 2026
Short summary
Short summary
There is a dangerous amount of uncertainty in our predictions of climate change in polar regions because some of feedbacks that might lead to changes that are too rapid for us to adapt to, or that cannot be reversed. We have run a set of simulations with a state-of-the-art Earth System Model that helps improve our understanding of how climate in these regions might change. Some of the aspects we investigate are reversible but many are not, especially those affecting ice sheets and sea level.
Claire K. Yung, Xylar S. Asay-Davis, Alistair Adcroft, Christopher Y. S. Bull, Jan De Rydt, Michael S. Dinniman, Benjamin K. Galton-Fenzi, Daniel Goldberg, David E. Gwyther, Robert Hallberg, Matthew Harrison, Tore Hattermann, David M. Holland, Denise Holland, Paul R. Holland, James R. Jordan, Nicolas C. Jourdain, Kazuya Kusahara, Gustavo Marques, Pierre Mathiot, Dimitris Menemenlis, Adele K. Morrison, Yoshihiro Nakayama, Olga Sergienko, Robin S. Smith, Alon Stern, Ralph Timmermann, and Qin Zhou
The Cryosphere, 20, 2053–2088, https://doi.org/10.5194/tc-20-2053-2026, https://doi.org/10.5194/tc-20-2053-2026, 2026
Short summary
Short summary
The second Ice Shelf-Ocean Model Intercomparison Project, ISOMIP+, compares 12 ice shelf-ocean models with a common, idealised, static configuration, aiming to assess inter-model variability. Models show similar basal melt rate patterns, ocean profiles and circulation but differ in ice-ocean boundary layer properties. Ice-ocean boundary layer representation is a key area for future work, as are realistic-domain ice sheet-ocean model intercomparisons.
Rasmus Tage Tonboe, Vishnu Nandan, Marcus Huntemann, Julienne Stroeve, Randall Scharien, John Yackel, Lars Kaleschke, Hoyeon Shi, and Tânia Casal
EGUsphere, https://doi.org/10.5194/egusphere-2026-1440, https://doi.org/10.5194/egusphere-2026-1440, 2026
Short summary
Short summary
Scattering and absorption from air bubbles, voids, and brine pockets significantly affect radar and microwave radiometer measurements of sea ice and light propagation through sea ice. Here, we used a high-resolution dataset, collected during the 2019–20 MOSAiC expedition, of thin ice slices of various Arctic sea ice types to estimate the autocorrelation length and density of the inclusions. The data can be used to initialize sea ice scattering models and for understanding satellite data.
William J. Dow, Amanda C. Maycock, Andrew N. Ross, Ryan S. Williams, and Thomas J. Bracegirdle
EGUsphere, https://doi.org/10.5194/egusphere-2026-1179, https://doi.org/10.5194/egusphere-2026-1179, 2026
Short summary
Short summary
This study aims to advance understanding of the atmospheric drivers of extreme warm days across the Antarctic Peninsula during summer. We find that these days are linked to a range of large-scale atmospheric circulation patterns. Using a statistical method, we grouped similar events and compared their wind, temperature and pressure features, showing clear differences spatially and temporally. Understanding these dynamics improves understanding of the processes that drive these extreme events.
David T. Bett, Alexander T. Bradley, Bertie W. J. Miles, C. Rosie Williams, Paul R. Holland, and Robert J. Arthern
EGUsphere, https://doi.org/10.5194/egusphere-2026-669, https://doi.org/10.5194/egusphere-2026-669, 2026
Short summary
Short summary
An ice-ocean model is used to explore the 20th-century evolution of Thwaites Glacier, Antarctica. Several processes are involved as the ice retreats to its present-day state, including ocean melting, the floatation of a historically-grounded ice island, ice crevassing and damage, and changing of ice-flow patterns. Multiple options for steady historical Thwaites Glacier configurations are found, with these options compared against 1940s aerial imagery and evidence from seabed sediments.
Archie Cable, Thomas Caton Harrison, Elizabeth Kent, Richard Cornes, and Thomas J. Bracegirdle
Weather Clim. Dynam., 7, 247–262, https://doi.org/10.5194/wcd-7-247-2026, https://doi.org/10.5194/wcd-7-247-2026, 2026
Short summary
Short summary
Winds around the Antarctic coast have global importance. With influences from competing drivers, their structure is complex so it is hard to understand how they will change in the future. We develop a simple measure that identifies key features in the coastal winds, including their northern extent. Using climate models, we analyse future projections of this boundary and find that it will shift polewards, shrinking the Antarctic coastal wind region.
Yavor Kostov, Paul R. Holland, Kelly A. Hogan, James A. Smith, Nicolas C. Jourdain, Pierre Mathiot, Anna Olivé Abelló, Andrew H. Fleming, and Andrew J. S. Meijers
The Cryosphere, 20, 135–169, https://doi.org/10.5194/tc-20-135-2026, https://doi.org/10.5194/tc-20-135-2026, 2026
Short summary
Short summary
Icebergs ground when they reach shallow topography such as Bear Ridge in the Amundsen Sea. Grounded icebergs can block the transport of sea-ice and create areas of higher and lower sea-ice concentration. We introduce a physically and observationally motivated representation of grounding in an ocean model. In addition, we improve the way simulated icebergs respond to winds, ocean currents, and density differences in sea water. We analyse the forces acting on freely floating and grounded icebergs.
Gavin A. Schmidt, Kenneth D. Mankoff, Jonathan L. Bamber, Clara Burgard, Dustin Carroll, David M. Chandler, Violaine Coulon, Benjamin J. Davison, Matthew H. England, Paul R. Holland, Nicolas C. Jourdain, Qian Li, Juliana M. Marson, Pierre Mathiot, Clive R. McMahon, Twila A. Moon, Ruth Mottram, Sophie Nowicki, Anna Olivé Abelló, Andrew G. Pauling, Thomas Rackow, and Damien Ringeisen
Geosci. Model Dev., 18, 8333–8361, https://doi.org/10.5194/gmd-18-8333-2025, https://doi.org/10.5194/gmd-18-8333-2025, 2025
Short summary
Short summary
The impact of increasing mass loss from the Greenland and Antarctic ice sheets has not so far been included in historical climate model simulations. This paper describes the protocols and data available for modeling groups to add this anomalous freshwater to their ocean modules to better represent the impacts of these fluxes on ocean circulation, sea ice, salinity and sea level.
Nicole A. Loeb, Alex Crawford, Brice Noël, and Julienne Stroeve
The Cryosphere, 19, 5403–5422, https://doi.org/10.5194/tc-19-5403-2025, https://doi.org/10.5194/tc-19-5403-2025, 2025
Short summary
Short summary
We examine how extreme precipitation days affect the seasonal mass balance (SMB) of land ice in Greenland and the Eastern Canadian Arctic in historical and future simulations. Past extreme precipitation led to higher SMB with snowfall. Future extreme precipitation may lead to the loss of ice mass as more falls as rain rather than snow in some regions, such as southwestern Greenland. Across the region, extreme precipitation becomes more important to seasonal SMB in the future, warmer climate.
Katie Lowery, Pierre Dutrieux, Paul R. Holland, Anna E. Hogg, Noel Gourmelen, and Benjamin J. Wallis
The Cryosphere, 19, 4893–4911, https://doi.org/10.5194/tc-19-4893-2025, https://doi.org/10.5194/tc-19-4893-2025, 2025
Short summary
Short summary
Using CryoSat-2, we observe monthly changes in the Pine Island Glacier (PIG) ice shelf surface and derive oceanic melt at its base. Basal channels, kilometres wide, are reflected in the ice surface and captured in our observations. We demonstrate that melt is concentrated on the western walls of channels, that channels play a role in grounding pinning points, and that PIG's main channel geometry is inherited upstream of the grounding line. These results highlight the importance of channels to ice shelf stability.
Renée Mie Fredensborg Hansen, Henriette Skourup, Eero Rinne, Arttu Jutila, Isobel R. Lawrence, Andrew Shepherd, Knut Vilhelm Høyland, Jilu Li, Fernando Rodriguez-Morales, Sebastian Bjerregaaard Simonsen, Jeremy Wilkinson, Gaelle Veyssiere, Donghui Yi, René Forsberg, and Taniâ Gil Duarte Casal
The Cryosphere, 19, 4167–4192, https://doi.org/10.5194/tc-19-4167-2025, https://doi.org/10.5194/tc-19-4167-2025, 2025
Short summary
Short summary
An airborne campaign collected unprecedented coincident multi-frequency radar and lidar data over sea ice along a CryoSat-2 and ICESat-2 (CRYO2ICE) orbit in the Weddell Sea, useful for evaluating microwave snow penetration. Ka-band and Ku-band had limited penetration with significant contributions from the air–snow interface, contradicting traditional assumptions with discrepancies between commonly used C/S-band "snow-radar" methodologies, all challenging comparisons of airborne and spaceborne estimates.
Renée Mie Fredensborg Hansen, Henriette Skourup, Eero Rinne, Arttu Jutila, Isobel R. Lawrence, Andrew Shepherd, Knut Vilhelm Høyland, Jilu Li, Fernando Rodriguez-Morales, Sebastian Bjerregaaard Simonsen, Jeremy Wilkinson, Gaelle Veyssiere, Donghui Yi, René Forsberg, and Taniâ Gil Duarte Casal
The Cryosphere, 19, 4193–4209, https://doi.org/10.5194/tc-19-4193-2025, https://doi.org/10.5194/tc-19-4193-2025, 2025
Short summary
Short summary
An airborne campaign collected unprecedented coincident multi-frequency radar and lidar data over sea ice along a CryoSat-2 and ICESat-2 (CRYO2ICE) orbit in the Weddell Sea, useful for evaluating microwave snow penetration. Ka-band and Ku-band had limited penetration with significant contributions from the air–snow interface, contradicting traditional assumptions with discrepancies between commonly used C/S-band "snow-radar" methodologies, all challenging comparisons of airborne and spaceborne estimates.
Vaishali Chaudhary, Julienne Stroeve, Vishnu Nandan, and Dustin Isleifson
EGUsphere, https://doi.org/10.5194/egusphere-2025-2851, https://doi.org/10.5194/egusphere-2025-2851, 2025
Preprint archived
Short summary
Short summary
This study examines how changing weather is affecting sea ice near the Arctic community of Tuktoyaktuk in Canada. Using satellite images and weather records, we found that stronger winds from certain directions are causing the sea ice to break more often in winter. These changes pose risks for local people who depend on stable ice for travel and hunting. Our findings help understand how climate change is making Arctic ice less reliable and more dangerous.
Franck Eitel Kemgang Ghomsi, Muharrem Hilmi Erkoç, Roshin P. Raj, Atinç Pirti, Antonio Bonaduce, Babatunde J. Abiodun, and Julienne Stroeve
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLVIII-M-6-2025, 393–397, https://doi.org/10.5194/isprs-archives-XLVIII-M-6-2025-393-2025, https://doi.org/10.5194/isprs-archives-XLVIII-M-6-2025-393-2025, 2025
Monojit Saha, Julienne Stroeve, Dustin Isleifson, John Yackel, Vishnu Nandan, Jack Christopher Landy, and Hoi Ming Lam
The Cryosphere, 19, 325–346, https://doi.org/10.5194/tc-19-325-2025, https://doi.org/10.5194/tc-19-325-2025, 2025
Short summary
Short summary
Snow on sea ice is vital for near-shore sea ice geophysical and biological processes. Past studies have measured snow depths using the satellite altimeters Cryosat-2 and ICESat-2 (Cryo2Ice), but estimating sea surface height from leadless landfast sea ice remains challenging. Snow depths from Cryo2Ice are compared to in situ data after adjusting for tides. Realistic snow depths are retrieved, but differences in roughness, satellite footprints, and snow geophysical properties are identified.
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
Short summary
Short summary
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.
Lu Zhou, Julienne Stroeve, Vishnu Nandan, Rosemary Willatt, Shiming Xu, Weixin Zhu, Sahra Kacimi, Stefanie Arndt, and Zifan Yang
The Cryosphere, 18, 4399–4434, https://doi.org/10.5194/tc-18-4399-2024, https://doi.org/10.5194/tc-18-4399-2024, 2024
Short summary
Short summary
Snow over Antarctic sea ice, influenced by highly variable meteorological conditions and heavy snowfall, has a complex stratigraphy and profound impact on the microwave signature. We employ advanced radiation transfer models to analyse the effects of complex snow properties on brightness temperatures over the sea ice in the Southern Ocean. Great potential lies in the understanding of snow processes and the application to satellite retrievals.
Nicolaj Hansen, Andrew Orr, Xun Zou, Fredrik Boberg, Thomas J. Bracegirdle, Ella Gilbert, Peter L. Langen, Matthew A. Lazzara, Ruth Mottram, Tony Phillips, Ruth Price, Sebastian B. Simonsen, and Stuart Webster
The Cryosphere, 18, 2897–2916, https://doi.org/10.5194/tc-18-2897-2024, https://doi.org/10.5194/tc-18-2897-2024, 2024
Short summary
Short summary
We investigated a melt event over the Ross Ice Shelf. We use regional climate models and a firn model to simulate the melt and compare the results with satellite data. We find that the firn model aligned well with observed melt days in certain parts of the ice shelf. The firn model had challenges accurately simulating the melt extent in the western sector. We identified potential reasons for these discrepancies, pointing to limitations in the models related to representing the cloud properties.
David T. Bett, Alexander T. Bradley, C. Rosie Williams, Paul R. Holland, Robert J. Arthern, and Daniel N. Goldberg
The Cryosphere, 18, 2653–2675, https://doi.org/10.5194/tc-18-2653-2024, https://doi.org/10.5194/tc-18-2653-2024, 2024
Short summary
Short summary
A new ice–ocean model simulates future ice sheet evolution in the Amundsen Sea sector of Antarctica. Substantial ice retreat is simulated in all scenarios, with some retreat still occurring even with no future ocean melting. The future of small "pinning points" (islands of ice that contact the seabed) is an important control on this retreat. Ocean melting is crucial in causing these features to go afloat, providing the link by which climate change may affect this sector's sea level contribution.
Wiebke Margitta Kolbe, Rasmus T. Tonboe, and Julienne Stroeve
Earth Syst. Sci. Data, 16, 1247–1264, https://doi.org/10.5194/essd-16-1247-2024, https://doi.org/10.5194/essd-16-1247-2024, 2024
Short summary
Short summary
Current satellite-based sea-ice climate data records (CDRs) usually begin in October 1978 with the first multichannel microwave radiometer data. Here, we present a sea ice dataset based on the single-channel Electrical Scanning Microwave Radiometer (ESMR) that operated from 1972-1977 onboard NASA’s Nimbus 5 satellite. The data were processed using modern methods and include uncertainty estimations in order to provide an important, easy-to-use reference period of good quality for current CDRs.
Qinggang Gao, Louise C. Sime, Alison J. McLaren, Thomas J. Bracegirdle, Emilie Capron, Rachael H. Rhodes, Hans Christian Steen-Larsen, Xiaoxu Shi, and Martin Werner
The Cryosphere, 18, 683–703, https://doi.org/10.5194/tc-18-683-2024, https://doi.org/10.5194/tc-18-683-2024, 2024
Short summary
Short summary
Antarctic precipitation is a crucial component of the climate system. Its spatio-temporal variability impacts sea level changes and the interpretation of water isotope measurements in ice cores. To better understand its climatic drivers, we developed water tracers in an atmospheric model to identify moisture source conditions from which precipitation originates. We find that mid-latitude surface winds exert an important control on moisture availability for Antarctic precipitation.
Alistair Duffey, Robbie Mallett, Peter J. Irvine, Michel Tsamados, and Julienne Stroeve
Earth Syst. Dynam., 14, 1165–1169, https://doi.org/10.5194/esd-14-1165-2023, https://doi.org/10.5194/esd-14-1165-2023, 2023
Short summary
Short summary
The Arctic is warming several times faster than the rest of the planet. Here, we use climate model projections to quantify for the first time how this faster warming in the Arctic impacts the timing of crossing the 1.5 °C and 2 °C thresholds defined in the Paris Agreement. We show that under plausible emissions scenarios that fail to meet the Paris 1.5 °C target, a hypothetical world without faster warming in the Arctic would breach that 1.5 °C target around 5 years later.
Gemma K. O'Connor, Paul R. Holland, Eric J. Steig, Pierre Dutrieux, and Gregory J. Hakim
The Cryosphere, 17, 4399–4420, https://doi.org/10.5194/tc-17-4399-2023, https://doi.org/10.5194/tc-17-4399-2023, 2023
Short summary
Short summary
Glaciers in West Antarctica are rapidly melting, but the causes are unknown due to limited observations. A leading hypothesis is that an unusually large wind event in the 1940s initiated the ocean-driven melting. Using proxy reconstructions (e.g., using ice cores) and climate model simulations, we find that wind events similar to the 1940s event are relatively common on millennial timescales, implying that ocean variability or climate trends are also necessary to explain the start of ice loss.
Erwin Lambert, André Jüling, Roderik S. W. van de Wal, and Paul R. Holland
The Cryosphere, 17, 3203–3228, https://doi.org/10.5194/tc-17-3203-2023, https://doi.org/10.5194/tc-17-3203-2023, 2023
Short summary
Short summary
A major uncertainty in the study of sea level rise is the melting of the Antarctic ice sheet by the ocean. Here, we have developed a new model, named LADDIE, that simulates this ocean-driven melting of the floating parts of the Antarctic ice sheet. This model simulates fine-scale patterns of melting and freezing and requires significantly fewer computational resources than state-of-the-art ocean models. LADDIE can be used as a new tool to force high-resolution ice sheet models.
Vishnu Nandan, Rosemary Willatt, Robbie Mallett, Julienne Stroeve, Torsten Geldsetzer, Randall Scharien, Rasmus Tonboe, John Yackel, Jack Landy, David Clemens-Sewall, Arttu Jutila, David N. Wagner, Daniela Krampe, Marcus Huntemann, Mallik Mahmud, David Jensen, Thomas Newman, Stefan Hendricks, Gunnar Spreen, Amy Macfarlane, Martin Schneebeli, James Mead, Robert Ricker, Michael Gallagher, Claude Duguay, Ian Raphael, Chris Polashenski, Michel Tsamados, Ilkka Matero, and Mario Hoppmann
The Cryosphere, 17, 2211–2229, https://doi.org/10.5194/tc-17-2211-2023, https://doi.org/10.5194/tc-17-2211-2023, 2023
Short summary
Short summary
We show that wind redistributes snow on Arctic sea ice, and Ka- and Ku-band radar measurements detect both newly deposited snow and buried snow layers that can affect the accuracy of snow depth estimates on sea ice. Radar, laser, meteorological, and snow data were collected during the MOSAiC expedition. With frequent occurrence of storms in the Arctic, our results show that
wind-redistributed snow needs to be accounted for to improve snow depth estimates on sea ice from satellite radars.
Younjoo J. Lee, Wieslaw Maslowski, John J. Cassano, Jaclyn Clement Kinney, Anthony P. Craig, Samy Kamal, Robert Osinski, Mark W. Seefeldt, Julienne Stroeve, and Hailong Wang
The Cryosphere, 17, 233–253, https://doi.org/10.5194/tc-17-233-2023, https://doi.org/10.5194/tc-17-233-2023, 2023
Short summary
Short summary
During 1979–2020, four winter polynyas occurred in December 1986 and February 2011, 2017, and 2018 north of Greenland. Instead of ice melting due to the anomalous warm air intrusion, the extreme wind forcing resulted in greater ice transport offshore. Based on the two ensemble runs, representing a 1980s thicker ice vs. a 2010s thinner ice, a dominant cause of these winter polynyas stems from internal variability of atmospheric forcing rather than from the forced response to a warming climate.
Paul R. Holland, Gemma K. O'Connor, Thomas J. Bracegirdle, Pierre Dutrieux, Kaitlin A. Naughten, Eric J. Steig, David P. Schneider, Adrian Jenkins, and James A. Smith
The Cryosphere, 16, 5085–5105, https://doi.org/10.5194/tc-16-5085-2022, https://doi.org/10.5194/tc-16-5085-2022, 2022
Short summary
Short summary
The Antarctic Ice Sheet is losing ice, causing sea-level rise. However, it is not known whether human-induced climate change has contributed to this ice loss. In this study, we use evidence from climate models and palaeoclimate measurements (e.g. ice cores) to suggest that the ice loss was triggered by natural climate variations but is now sustained by human-forced climate change. This implies that future greenhouse-gas emissions may influence sea-level rise from Antarctica.
Thomas Caton Harrison, Stavroula Biri, Thomas J. Bracegirdle, John C. King, Elizabeth C. Kent, Étienne Vignon, and John Turner
Weather Clim. Dynam., 3, 1415–1437, https://doi.org/10.5194/wcd-3-1415-2022, https://doi.org/10.5194/wcd-3-1415-2022, 2022
Short summary
Short summary
Easterly winds encircle Antarctica, impacting sea ice and helping drive ocean currents which shield ice shelves from warmer waters. Reanalysis datasets give us our most complete picture of how these winds behave. In this paper we use satellite data, surface measurements and weather balloons to test how realistic recent reanalysis estimates are. The winds are generally accurate, especially in the most recent of the datasets, but important short-term variations are often misrepresented.
Julienne Stroeve, Vishnu Nandan, Rosemary Willatt, Ruzica Dadic, Philip Rostosky, Michael Gallagher, Robbie Mallett, Andrew Barrett, Stefan Hendricks, Rasmus Tonboe, Michelle McCrystall, Mark Serreze, Linda Thielke, Gunnar Spreen, Thomas Newman, John Yackel, Robert Ricker, Michel Tsamados, Amy Macfarlane, Henna-Reetta Hannula, and Martin Schneebeli
The Cryosphere, 16, 4223–4250, https://doi.org/10.5194/tc-16-4223-2022, https://doi.org/10.5194/tc-16-4223-2022, 2022
Short summary
Short summary
Impacts of rain on snow (ROS) on satellite-retrieved sea ice variables remain to be fully understood. This study evaluates the impacts of ROS over sea ice on active and passive microwave data collected during the 2019–20 MOSAiC expedition. Rainfall and subsequent refreezing of the snowpack significantly altered emitted and backscattered radar energy, laying important groundwork for understanding their impacts on operational satellite retrievals of various sea ice geophysical variables.
Antony Siahaan, Robin S. Smith, Paul R. Holland, Adrian Jenkins, Jonathan M. Gregory, Victoria Lee, Pierre Mathiot, Antony J. Payne, Jeff K. Ridley, and Colin G. Jones
The Cryosphere, 16, 4053–4086, https://doi.org/10.5194/tc-16-4053-2022, https://doi.org/10.5194/tc-16-4053-2022, 2022
Short summary
Short summary
The UK Earth System Model is the first to fully include interactions of the atmosphere and ocean with the Antarctic Ice Sheet. Under the low-greenhouse-gas SSP1–1.9 (Shared Socioeconomic Pathway) scenario, the ice sheet remains stable over the 21st century. Under the strong-greenhouse-gas SSP5–8.5 scenario, the model predicts strong increases in melting of large ice shelves and snow accumulation on the surface. The dominance of accumulation leads to a sea level fall at the end of the century.
David N. Wagner, Matthew D. Shupe, Christopher Cox, Ola G. Persson, Taneil Uttal, Markus M. Frey, Amélie Kirchgaessner, Martin Schneebeli, Matthias Jaggi, Amy R. Macfarlane, Polona Itkin, Stefanie Arndt, Stefan Hendricks, Daniela Krampe, Marcel Nicolaus, Robert Ricker, Julia Regnery, Nikolai Kolabutin, Egor Shimanshuck, Marc Oggier, Ian Raphael, Julienne Stroeve, and Michael Lehning
The Cryosphere, 16, 2373–2402, https://doi.org/10.5194/tc-16-2373-2022, https://doi.org/10.5194/tc-16-2373-2022, 2022
Short summary
Short summary
Based on measurements of the snow cover over sea ice and atmospheric measurements, we estimate snowfall and snow accumulation for the MOSAiC ice floe, between November 2019 and May 2020. For this period, we estimate 98–114 mm of precipitation. We suggest that about 34 mm of snow water equivalent accumulated until the end of April 2020 and that at least about 50 % of the precipitated snow was eroded or sublimated. Further, we suggest explanations for potential snowfall overestimation.
William Gregory, Julienne Stroeve, and Michel Tsamados
The Cryosphere, 16, 1653–1673, https://doi.org/10.5194/tc-16-1653-2022, https://doi.org/10.5194/tc-16-1653-2022, 2022
Short summary
Short summary
This research was conducted to better understand how coupled climate models simulate one of the large-scale interactions between the atmosphere and Arctic sea ice that we see in observational data, the accurate representation of which is important for producing reliable forecasts of Arctic sea ice on seasonal to inter-annual timescales. With network theory, this work shows that models do not reflect this interaction well on average, which is likely due to regional biases in sea ice thickness.
Isolde A. Glissenaar, Jack C. Landy, Alek A. Petty, Nathan T. Kurtz, and Julienne C. Stroeve
The Cryosphere, 15, 4909–4927, https://doi.org/10.5194/tc-15-4909-2021, https://doi.org/10.5194/tc-15-4909-2021, 2021
Short summary
Short summary
Scientists can estimate sea ice thickness using satellites that measure surface height. To determine the sea ice thickness, we also need to know the snow depth and density. This paper shows that the chosen snow depth product has a considerable impact on the findings of sea ice thickness state and trends in Baffin Bay, showing mean thinning with some snow depth products and mean thickening with others. This shows that it is important to better understand and monitor snow depth on sea ice.
Cited articles
Bracegirdle, T. J., Stephenson, D. B., Turner, J., and Phillips, T.: The importance of sea ice area biases in 21st century multimodel projections of Antarctic temperature and precipitation, Geophys. Res. Lett., 42, 10832–10839, https://doi.org/10.1002/2015GL067055, 2015.
Bracegirdle, T. J., Hyder, P., and Holmes, C. R.: CMIP5 diversity in southern westerly jet projections related to historical sea ice area: Strong link to strengthening and weak link to shift, J. Climate, 31, 195–211, https://doi.org/10.1175/JCLI-D-17-0320.1, 2018.
Cavalieri, D., Parkinson, C., and Vinnikov, K. Y.: 30-Year satellite record reveals contrasting Arctic and Antarctic decadal sea ice variability, Geophys. Res. Lett., 30, 1970, https://doi.org/10.1029/2003GL018031, 2003.
Diamond, R., Sime, L. C., Schroeder, D., and Holmes, C. R.: CMIP6 models rarely simulate Antarctic winter sea-ice anomalies as large as observed in 2023, Geophys. Res. Lett., 51, e2024GL109265, https://doi.org/10.1029/2024GL109265, 2024.
Dörr, J., Dirk, N., and Kern, S.: UHH sea-ice area product, 1850–2019 (v2019_fv0.01), UHH [data set], https://doi.org/10.25592/uhhfdm.8559, 2021.
Eyring, V., Bony, S., Meehl, G. A., Senior, C. A., Stevens, B., Stouffer, R. J., and Taylor, K. E.: Overview of the Coupled Model Intercomparison Project Phase 6 (CMIP6) experimental design and organization, Geosci. Model Dev., 9, 1937–1958, https://doi.org/10.5194/gmd-9-1937-2016, 2016.
Ferreira, D., Marshall, J., Bitz, C. M., Solomon, S., and Plumb, A.: Antarctic Ocean and sea ice response to ozone depletion: A two-time-scale problem, J. Climate, 28, 1206–1226, https://doi.org/10.1175/JCLI-D-14-00313.1, 2015.
Fetterer, F., Knowles, K., Meier, W. N., Savoie, M., and Windnagel, A. K.: Sea Ice Index. (G02135, Version 3), Boulder, Colorado USA, National Snow and Ice Data Center [data set], https://doi.org/10.7265/N5K072F8 (last access: 26 January 2024), 2017.
Fogt, R. L., Sleinkofer, A. M., Raphael, M. N., and Handcock, M. S.: A regime shift in seasonal total Antarctic sea ice extent in the twentieth century, Nat. Clim. Change, 12, 54–62, https://doi.org/10.1038/s41558-021-01254-9, 2022.
Fox-Kemper, B., Hewitt, H. T., Xiao, C., Aðalgeirsdóttir, G., Drijfhout, S. S., Edwards, T. L., Golledge, N. R., Hemer, M., Kopp, R. E., Krinner, G., Mix, A., Notz, D., Nowicki, S., Nurhati, I. S., Ruiz, L., Sallée, J.-B., Slangen, A. B. A., and Yu, Y.: Ocean, Cryosphere and Sea Level Change, in: In Climate Change 2021 – The Physical Science Basis: Working Group I Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, 1211–1362, https://doi.org/10.1017/9781009157896.011, 2021.
Gagné, M. È., Gillett, N., and Fyfe, J.: Observed and simulated changes in Antarctic sea ice extent over the past 50 years, Geophys. Res. Lett., 42, 90–95, https://doi.org/10.1002/2014GL062231, 2015.
Gallaher, D. W., Campbell, G. G., and Meier, W. N.: Anomalous variability in Antarctic sea ice extents during the 1960s with the use of Nimbus data, IEEE J. Sel. Top. Appl. Earth Obs., 7, 881–887, https://doi.org/10.1109/JSTARS.2013.2264391, 2013.
Gupta, A. S., Jourdain, N. C., Brown, J. N., and Monselesan, D.: Climate Drift in the CMIP5 Models, J. Climate, 26, 8597–8615, https://doi.org/10.1175/JCLI-D-12-00521.1, 2013.
Hawkins, E. and Sutton, R.: Time of emergence of climate signals, Geophys. Res. Lett., 39, L01702, https://doi.org/10.1029/2011GL050087, 2012.
Hobbs, W. R., Bindoff, N. L., and Raphael, M. N.: New Perspectives on Observed and Simulated Antarctic Sea Ice Extent Trends Using Optimal Fingerprinting Techniques, J. Climate, 28, 1543–1560, https://doi.org/10.1175/JCLI-D-14-00367.1, 2015.
Hobbs, W., Spence, P., Meyer, A., Schroeter, S., Fraser, A., Reid, P., Tian, T., Wang, Z., Liniger, G., Doddridge, E. and Boyd, P.: Observational Evidence for a Regime Shift in Summer Antarctic Sea Ice, J. Climate, 37, 2263–2275, https://doi.org/10.1175/JCLI-D-23-0479.1, 2024.
Holmes, C., Bracegirdle, T., and Holland, P.: Antarctic sea ice projections constrained by historical ice cover and future global temperature change, Geophys. Res. Lett., 49, e2021GL097413, https://doi.org/10.1029/2021GL097413, 2022.
Holmes, C. R., Holland, P. R., and Bracegirdle, T. J.: Compensating biases and a noteworthy success in the CMIP5 representation of Antarctic sea ice processes, Geophys. Res. Lett., 46, 4299–4307, https://doi.org/10.1029/2018GL081796, 2019.
Kostov, Y., Marshall, J., Hausmann, U., Armour, K. C., Ferreira, D., and Holland, M. M.: Fast and slow responses of Southern Ocean sea surface temperature to SAM in coupled climate models, Clim. Dynam., 48, 1595–1609, https://doi.org/10.1007/s00382-016-3162-z, 2017.
Lavergne, T., Sørensen, A. M., Kern, S., Tonboe, R., Notz, D., Aaboe, S., Bell, L., Dybkjær, G., Eastwood, S., Gabarro, C., Heygster, G., Killie, M. A., Brandt Kreiner, M., Lavelle, J., Saldo, R., Sandven, S., and Pedersen, L. T.: Version 2 of the EUMETSAT OSI SAF and ESA CCI sea-ice concentration climate data records, The Cryosphere, 13, 49–78, https://doi.org/10.5194/tc-13-49-2019, 2019.
Meier, W. N., Gallaher, D., and Campbell, G. G.: New estimates of Arctic and Antarctic sea ice extent during September 1964 from recovered Nimbus I satellite imagery, The Cryosphere, 7, 699–705, https://doi.org/10.5194/tc-7-699-2013, 2013.
National Academies of Sciences, Engineering, and Medicine: Antarctic Sea Ice Variability in the Southern Ocean-Climate System, Proceedings of a Workshop, Washington, DC, The National Academies Press, https://doi.org/10.17226/24696, 2017.
Notz, D.: Sea-ice extent and its trend provide limited metrics of model performance, The Cryosphere, 8, 229–243, https://doi.org/10.5194/tc-8-229-2014, 2014.
Notz, D. and Kern, S.: CMIP6 Sea Ice Area Directory, version V02, University of Hamburg, https://www.cen.uni-hamburg.de/en/icdc/data/cryosphere/cmip6-sea-ice-area.html (last access: 17 August 2023), 2023.
O'Neill, B. C., Tebaldi, C., van Vuuren, D. P., Eyring, V., Friedlingstein, P., Hurtt, G., Knutti, R., Kriegler, E., Lamarque, J.-F., Lowe, J., Meehl, G. A., Moss, R., Riahi, K., and Sanderson, B. M.: The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6, Geosci. Model Dev., 9, 3461–3482, https://doi.org/10.5194/gmd-9-3461-2016, 2016.
Parkinson, C. L.: A 40-y record reveals gradual Antarctic sea ice increases followed by decreases at rates far exceeding the rates seen in the Arctic, P. Natl. Acad. Sci. USA, 116, 14414–14423, https://doi.org/10.1073/pnas.1906556116, 2019.
Polvani, L. M. and Smith, K. L.: Can natural variability explain observed Antarctic sea ice trends? New modeling evidence from CMIP5, Geophys. Res. Lett., 40, 3195–3199, https://doi.org/10.1002/grl.50578, 2013.
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.
Roach, L. A., Dörr, J., Holmes, C. R., Massonnet, F., Blockley, E. W., Notz, D., Rackow, T., Raphael, M. N., O'Farrell, S. P., Bailey, D. A., and Bitz, C. M.: Antarctic Sea Ice Area in CMIP6, Geophys. Res. Lett., 47, e2019GL086729, https://doi.org/10.1029/2019GL086729, 2020.
Rosenblum, E. and Eisenman, I.: Sea ice trends in climate models only accurate in runs with biased global warming, J. Climate, 30, 6265–6278, https://doi.org/10.1175/JCLI-D-16-0455.1, 2017.
Schlosser, E., Haumann, F. A., and Raphael, M. N.: Atmospheric influences on the anomalous 2016 Antarctic sea ice decay, The Cryosphere, 12, 1103–1119, https://doi.org/10.5194/tc-12-1103-2018, 2018.
Schneider, D. P. and Deser, C.: Tropically driven and externally forced patterns of Antarctic sea ice change: Reconciling observed and modeled trends, Clim. Dynam., 50, 4599–4618, https://doi.org/10.1007/s00382-017-3893-5, 2018.
Schroeter, S., O'Kane, T. J., and Sandery, P. A.: Antarctic sea ice regime shift associated with decreasing zonal symmetry in the Southern Annular Mode, The Cryosphere, 17, 701–717, https://doi.org/10.5194/tc-17-701-2023, 2023.
Seviour, W., Codron, F., Doddridge, E. W., Ferreira, D., Gnanadesikan, A., Kelley, M., Kostov, Y., Marshall, J., Polvani, L., and Thomas, J.: The Southern Ocean sea surface temperature response to ozone depletion: A multimodel comparison, J. Climate, 32, 5107–5121, https://doi.org//10.1175/JCLI-D-19-0109.1, 2019.
Shu, Q., Wang, Q., Song, Z., Qiao, F., Zhao, J., Chu, M., and Li, X.: Assessment of sea ice extent in CMIP6 with comparison to observations and CMIP5, Geophys. Res. Lett., 47, e2020GL087965, https://doi.org/10.1029/2020GL087965, 2020.
Siegert, M. J., Bentley, M. J., Atkinson, A., Bracegirdle, T. J., Convey, P., Davies, B., Downie, R., Hogg, A. E., Holmes, C., and Hughes, K. A.: Antarctic extreme events, Front. Environ. Sci., 11, 1229283, https://doi.org/10.3389/fenvs.2023.1229283, 2023.
Swart, N. C., Martin, T., Beadling, R., Chen, J.-J., Danek, C., England, M. H., Farneti, R., Griffies, S. M., Hattermann, T., Hauck, J., Haumann, F. A., Jüling, A., Li, Q., Marshall, J., Muilwijk, M., Pauling, A. G., Purich, A., Smith, I. J., and Thomas, M.: The Southern Ocean Freshwater Input from Antarctica (SOFIA) Initiative: scientific objectives and experimental design, Geosci. Model Dev., 16, 7289–7309, https://doi.org/10.5194/gmd-16-7289-2023, 2023.
Turner, J. and Comiso, J.: Solve Antarctica's sea-ice puzzle, Nature, 547, 275–277, https://doi.org/10.1038/547275a, 2017.
Turner, J., Phillips, T., Marshall, G. J., Hosking, J. S., Pope, J. O., Bracegirdle, T. J., and Deb, P.: Unprecedented springtime retreat of Antarctic sea ice in 2016, Geophys. Res. Lett., 44, 6868–6875, https://doi.org/10.1002/2017GL073656, 2017.
Zhang, L., Delworth, T. L., Cooke, W., and Yang, X.: Natural variability of Southern Ocean convection as a driver of observed climate trends, Nat. Clim. Change, 9, 59–65, https://doi.org/10.1038/s41558-018-0350-3, 2019.
Zhang, L., Delworth, T. L., Yang, X., Zeng, F., Lu, F., Morioka, Y., and Bushuk, M.: The relative role of the subsurface Southern Ocean in driving negative Antarctic Sea ice extent anomalies in 2016–2021, Commun. Earth Environ., 3, 302, https://doi.org/10.1038/s43247-022-00624-1, 2022.
Zunz, V., Goosse, H., and Massonnet, F.: How does internal variability influence the ability of CMIP5 models to reproduce the recent trend in Southern Ocean sea ice extent?, The Cryosphere, 7, 451–468, https://doi.org/10.5194/tc-7-451-2013, 2013.
Short summary
Until recently, satellite data showed an increase in Antarctic sea ice area since 1979, but climate models simulated a decrease over this period. This mismatch was one reason for low confidence in model projections of 21st-century sea ice loss. We show that following low Antarctic sea ice in 2022 and 2023, we can no longer conclude that modelled and observed trends differ. However, differences in the manner of the decline mean that model sea ice projections should still be viewed with caution.
Until recently, satellite data showed an increase in Antarctic sea ice area since 1979, but...
