Friday 8th April, 2005
1:00 pm, M345 Building 28

 

Southern Ocean Circulation and Climate - model perspectives of the past, present and future

Dr. Matthew England
University of New South Wales
The role of the Southern Ocean in the Earth's climate system is assessed. This first involves exploring a series of simulations with a coupled model employing different geometries in the Drake Passage (DP) gap. We find that the North Atlantic thermohaline circulation depends not only on the existence of a DP throughflow, but also on the depth of the sills in the Southern Ocean. In contrast, Southern Hemisphere climate is highly sensitive to the existence of the DP, with the depth of the DP sill of secondary importance. Beyond this paleo-perspective, I will assess the Southern Ocean's role in regional climate and climate change on time scales of years to centuries. Of particular interest is: (i) the response of the climate system to latitude shifts in the subpolar westerly winds, (ii) Antarctic water-mass variability and its role in climate and (iii) the response of the Southern Ocean to Antarctic meltwater changes.