No longer polar opposites? Similarities in recent Arctic and Antarctic sea ice change

Le résumé fourni par la source

Until recently, trends in sea-ice cover in the Arctic and Antarctic seemed to follow opposite pathways. While Arctic sea ice showed a strong and prolonged decrease, Antarctic sea ice displayed a small but significant increase. Yet, in 2015, Antarctic sea ice experienced a sharp decline to an unprecedented summertime low in 2016 and a subsequent year-round minimum in 2023. These series of events have suggested the start of a sustained decline in Antarctic sea ice, similar to that in the Arctic. Meanwhile, the Arctic sea ice is transitioning towards a seasonal regime that resembles that of the Antarctic sea ice. These ongoing changes motivated the workshop on {\it The Role of Sea Ice and its Variability in the Climate System}, which brought together the Arctic and Antarctic research communities in July 2024 at the Abdus Salam International Centre for Theoretical Physics (ICTP) in Trieste, Italy. Here, we synthesize the discussions that took place during the workshop on changes in sea-ice properties as well as on oceanic and atmospheric drivers of these changes. We acknowledged that understanding these drivers requires enhanced observations of sea-ice parameters, such as thickness, improved process representation in models, such as ocean mesoscale eddies, and a more integrated approach to studying both polar regions. Our ability to predict sea ice changes, and hence assess future climate risks, depends on this refined understanding.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.