edu.ucar.opensky::articles:25599 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T20:07:33.803193 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7kh0s20 https://doi.org/10.1594/PANGAEA.943275 https Related Dataset #1 Southern Ocean marine sediment core sea-ice records for the last 150,000 years https://doi.org/10.7265/N5K072F8 https Related Dataset #2 Sea Ice Index, Version 3 Antarctic sea ice over the past 130 000 years – Part 1: A review of what proxy records tell us 2022-08-02T00:00:00Z publication https://n2t.org/ark:/85065/d7kh0s20 https://doi.org/10.5194/cp-18-1729-2022 Crosta, X. author Kohfeld, K. E. author Bostock, H. C. author Chadwick, M. author DuVivier, Alice K. author Esper, O. author Etourneau, J. author Jones, J. author Leventer, A. author Müller, J. author Rhodes, R. H. author Allen, C. S. author Ghadi, P. author Lamping, N. author Lange, C. B. author Lawler, K. author Lund, D. author Marzocchi, A. author Meissner, K. J. author Menviel, L. author Nair, A. author Patterson, M. author Pike, J. author Prebble, J. G. author Riesselman, C. author Sadatzki, H. author Sime, L. C. author Shukla, S. K. author Thöle, L. author Vorrath, M. author Xiao, W. author Yang, J. author UCAR/NCAR - Library publisher Antarctic sea ice plays a critical role in the Earth system, influencing energy, heat and freshwater fluxes, air-sea gas exchange, ice shelf dynamics, ocean circulation, nutrient cycling, marine productivity and global carbon cycling. However, accurate simulation of recent sea-ice changes remains challenging and, therefore, projecting future sea-ice changes and their influence on the global climate system is uncertain. Reconstructing past changes in sea-ice cover can provide additional insights into climate feedbacks within the Earth system at different timescales. This paper is the first of two review papers from the Cycles of Sea Ice Dynamics in the Earth system (C-SIDE) working group. In this first paper, we review marine- and ice core-based sea-ice proxies and reconstructions of sea-ice changes throughout the last glacial-interglacial cycle. Antarctic sea-ice reconstructions rely mainly on diatom fossil assemblages and highly branched isoprenoid (HBI) alkenes in marine sediments, supported by chemical proxies in Antarctic ice cores. Most reconstructions for the Last Glacial Maximum (LGM) suggest that winter sea ice expanded all around Antarctica and covered almost twice its modern surface extent. In contrast, LGM summer sea ice expanded mainly in the regions off the Weddell and Ross seas. The difference between winter and summer sea ice during the LGM led to a larger seasonal cycle than today. More recent efforts have focused on reconstructing Antarctic sea ice during warm periods, such as the Holocene and the Last Interglacial (LIG), which may serve as an analogue for the future. Notwithstanding regional heterogeneities, existing reconstructions suggest that sea-ice cover increased from the warm mid-Holocene to the colder Late Holocene with pervasive decadal- to millennial-scale variability throughout the Holocene. Studies, supported by proxy modelling experiments, suggest that sea-ice cover was halved during the warmer LIG when global average temperatures were ∼2 ∘C above the pre-industrial (PI). There are limited marine (14) and ice core (4) sea-ice proxy records covering the complete 130 000 year (130 ka) last glacial cycle. The glacial–interglacial pattern of sea-ice advance and retreat appears relatively similar in each basin of the Southern Ocean. Rapid retreat of sea ice occurred during Terminations II and I while the expansion of sea ice during the last glaciation appears more gradual especially in ice core data sets. Marine records suggest that the first prominent expansion occurred during Marine Isotope Stage (MIS) 4 and that sea ice reached maximum extent during MIS 2. We, however, note that additional sea-ice records and transient model simulations are required to better identify the underlying drivers and feedbacks of Antarctic sea-ice changes over the last 130 ka. This understanding is critical to improve future predictions. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. None eng geoscientificInformation