EESS Spring Seminar Series - Andrew Thompson, Assistant Professor, Environmental Science & Engineering, California Institute of Technology
EESS Spring Seminar Series - Andrew Thompson, Assistant Professor, Environmental Science & Engineering, California Institute of Technology, "The Antarctic Circumpolar Current in four dimensions", Abstract: In recent years, zonally-averaged theories of flow in the Southern Ocean has greatly improved our understanding of how eddy transport controls the stratification and meridional overturning of the Southern Ocean’s Antarctic Circumpolar Current (ACC). Yet, ocean GCMs and observations both show a large degree of zonal asymmetry in dynamical properties of the ACC. Eddy-mean flow interactions, which are responsible for generating and sustaining the characteristic heterogeneous frontal structure of the ACC, vary significantly along the path of the ACC with transitions between different regions largely controlled by topography. During this talk I will lay out a framework in which meridional transport in the Southern Ocean occurs in discrete locations determined by flow interactions with topography. A major ramification of this discrete view of the ACC is the potential sensitivity of global transport properties to local forcing changes. These localized "transport corridors" are also likely to play a leading order role in determining the ACC's longer term response to climate variations like the Southern Annular Mode.