Reconstructing Southern Ocean sea-ice dynamics on glacial-to-historical timescales

This special issue arises from the efforts of an international PAGES working group called Cycles of Sea-Ice Dynamics in the Earth System (C-SIDE), which aims to (a) reconstruct sea-ice conditions in the Southern Ocean over the last 130 000 years, (b) compare these reconstructions with complementary paleo-environmental data documenting changes in the Southern Ocean, and (c) use these data along with model simulations to improve our understanding of Earth system processes. The C-SIDE working group has chosen the last glacial–interglacial cycle (or last 130 000 years) as a focus because this timescale allows us to evaluate the role of sea ice on major climate transitions including glacial inception, when carbon was sequestered in the ocean, and deglaciation, when ocean carbon reserves were released to the atmosphere. The time frame also encompasses the penultimate interglacial when Antarctica was c. 2 °C warmer than today – a useful “process” analogue for future warming scenarios. At this time, the working group has held two workshops (October 2018 in Vancouver, Canada, and August/September 2019 in Sydney, Australia) to achieve these goals.

> Impact of Southern Ocean surface conditions on deep ocean circulation during the LGM: a model analysis

Fanny Lhardy, Nathaëlle Bouttes, Didier M. Roche, Xavier Crosta, Claire Waelbroeck, and Didier Paillard

Clim. Past, 17, 1139–1159, https://doi.org/10.5194/cp-17-1139-2021, 2021

> Sea ice dynamics in the Bransfield Strait, Antarctic Peninsula, during the past 240 years: a multi-proxy intercomparison study

Maria-Elena Vorrath, Juliane Müller, Lorena Rebolledo, Paola Cárdenas, Xiaoxu Shi, Oliver Esper, Thomas Opel, Walter Geibert, Práxedes Muñoz, Christian Haas, Gerhard Kuhn, Carina B. Lange, Gerrit Lohmann, and Gesine MollenhauerClim. Past, 16, 2459–2483, https://doi.org/10.5194/cp-16-2459-2020, 2020