Wednesday, May 27, 20153:00 PM - 4:00 PMCNLS Conference Room (TA-3, Bldg 1690)|
North Atlantic Vorticity Budget and the Gulf Stream Separation
Joseph SchoonoverFlorida State University
The Gulf Stream separation is a notoriously difficult feature to accurately simulate in general circulation models. The Community Earth System Model suffers from sea-surface temperature biases upwards of 7 K in the mid-Atlantic
Bight due to the unphysical northward separation of the modeled Gulf Stream. Results from an inter-model comparison study are presented which motivate the hypothesis that the Gulf Stream separation relies on local dynamics as opposed
to global vorticity and mass balance constraints. Models which produce a more northerly separation are shown to exhibit more viscous local vorticity balances. Of the local mechanisms suggested in oceanographic literature, it is argued that the steepening of the continental shelf in the vicinity of Cape Hatteras plays a pivotal role in the Gulf Stream separation.
Host: Wilbert Weijer