The Impact of Tropical Indian Ocean Warming on Southern Hemisphere Polar Climate


Dr. Judith Perlwitz
NOAA/CIRES
The impact of two distinct anthropogenic forcings on the Southern Hemisphere's (SH) polar climate is investigated using idealized climate model simulations. Chemical constituent changes are shown to drive a cooling of the polar stratosphere during spring and summer. Tropical Indian Ocean warming, itself a response to chemical constituent changes, drives a warming of the polar stratosphere, opposite to the local radiatively driven cooling. Our model experiments suggest that warming of the tropical Indian Ocean initiates a potent dynamical mechanism for changing high latitude climate, one that must be considered for accurate attribution of SH polar climate change.