Annular Modes and Stratospheric Memory
Contact: Edwin Gerber (gerber@cims.nyu.edu)
Summary: The annular mode patterns of variability can be used to characterize the coupling between the stratospheric polar night jets and the tropospheric mid-latitude jets and storm tracks. Variations in the planetary wave activity emanating from the troposphere drive variability in the strength of the stratospheric vortex, while stratospheric conditions in turn appear to influence the position of the tropospheric storm tracks. Within this DynVar Research Group, we are particularly interested in potential for the long time scales in the lower stratosphere, "stratospheric memory", to affect the persistence of tropospheric weather regimes. Can this coupling affect seasonal forecasts, and how important is it to the overall climate of the troposphere and stratosphere? We would also like to better understand the mechanism(s) behind the coupling.