Abstract

The CMIP5 climate models simulate a robust poleward shift and strengthening of the main eddy-driven belt of Southern Hemisphere (SH) mid-latitude near-surface westerly winds (hereinafter referred to as the ‘westerly jet’ or ‘jet’) in response to future scenarios of increased greenhouse gas concentrations. Such changes have wide-reaching implications both regionally and globally relating to impacts on, for example, uptake of thermal energy and CO2 in the Southern Ocean and ice-ocean interactions around Antarctica. However, there is a large inter-model spread in the magnitude of jet responses.

In this talk, recent and current research will be presented on impacts of sea ice retreat and ocean surface temperature change on the Southern mid-latitude tropospheric storm track and associated westerlies. New results will be shown that indicate robust aspects of responses across a range of different climate models. A look ahead to what might be expected from the CMIP6 models will also be presented.