MASS Seminar - Isla Simpson (LDEO)
Date Time Location
December 2nd, 2013 12:00pm-1:00pm 54-915
Title: "Understanding climate model biases in Southern Hemisphere mid-latitude
variability"

Abstract: The Southern Annular Mode (SAM) represents a latitudinal shifting of the
Southern Hemisphere (SH) jet stream and is the dominant mode of
variability in the SH mid-latitude circulation. A common bias among
global climate models is that they tend to exhibit SAM variability that
is much too persistent, particularly in the summer season. Many climate
forcings such as ozone depletion/recovery and increasing greenhouse gas
concentrations result in tropospheric circulation changes that project
strongly onto the SAM and therefore the inability of models to simulate
natural SAM variability correctly is of concern for the ability of such
models to accurately predict future circulation changes. Here the
underlying cause of this bias is investigated and results reveal a
common deficiency in the simulation of eddy-mean flow feedbacks in the
SH mid-latitudes.

Speaker's website: http://www.columbia.edu/~irs2113/