Description of the project

Context

Despite the progresses achieved over the last decade, many gaps in our knowledge of the processes that rule the variability of the sea ice extent in the Southern Ocean are still remaining. In particular, the recent positive trend in sea ice extent appears puzzling in a global warming context associated with a large temperature increase over the last 30 years and a strong decrease of the extent and volume of the large majority of the components of the cryosphere (snow cover, glaciers, Arctic sea ice, etc.). Several hypotheses have been proposed to explain this positive trend, partly attributing it to changes in the atmospheric circulation or in the oceanic stratification that would impact on the sea ice transport and the heat exchanges between the atmosphere, the ocean and sea ice. However, no clear conclusion has been obtained yet regarding the relative importance of various mechanisms.

Objectives

The goal of this project is firstly to improve our understanding of the mechanisms responsible for the recent changes in the Antarctic sea ice cover. Secondly, based on this improved understanding, we will be able to perform more accurate predictions and projections of the sea ice changes. Both predictions for the next decades and the projections for the end of the 21st century will be investigated. Decadal-scale is the main theme of this project but our results will also bring some new light on the longer term projections.