Sack Lunch Seminar (SLS)
Sack Lunch: Lynne Talley - University of California
Date |
Time |
Location |
December 9th, 2009 |
12:10pm-1:00pm |
54-912 |
Simplified Meridional Overturning Circulation and its Relation to
Heat and Freshwater Transport
The ocean's heat and freshwater transports are described in terms of various components of the
ocean's circulation, including the shallow gyres and deeper overturns, and vice versa. Salinity and hence
freshwater transport, which is set by the atmosphere's water vapor transport, is a central control on the grossest
aspects of the global overturn. The presence of Drake Passage creates the difference between northern and southern hemisphere overturn.
Freshwater transport through Bering Strait strongly affects the weak North Pacific Intermediate Water overturn,
but has only a small impact on North Atlantic Deep Water properties. A simplified global overturning schematic delineates
the equivalent impacts of the Atlantic (NADW production), Indian and Pacific
(upwelling from bottom waters into deep waters), and the Southern Ocean (upwelling of deep waters to the
surface and production of bottom water).