ABSTRACT:

Polar oceans play a crucial role in the response to climate change by taking up and redistributing excess heat and anthropogenic carbon produced by human activities, thus greatly mitigating the increase in global mean surface temperatures. Over recent decades, polar oceans have experienced significant changes including increases in air temperature, glacial melt and winds that are expected to further intensify over the 21st century. These changes have the potential to greatly impact anthropogenic carbon and heat uptake, with dramatic consequences for global sea level rise and warming.

In this presentation, I will focus on the Southern Ocean and give you a tour of some recent and ongoing projects on (i) the transport of heat, carbon and nutrients across the strong fronts of the Antarctic Circumpolar Current, (ii) the performance of models in representing the Southern Ocean carbon sink, and (iii) the response of Antarctic sea ice cover to climate change. These studies highlight some new challenges for numerical modelling and observational programs.

Though the Arctic Ocean shares some commonalities with the Southern Ocean, it also displays some major differences. I will conclude on how studying in more details these differences could shed some light on the respective responses of the Southern Ocean and Arctic Ocean to climate change.