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Impact of Last Glacial Maximum sea-level and surface-forcing changes on
heat and freshwater transports in the Gulf of Mexico in an eddy-permitting
ocean model
ABSTRACT
One of the most prominent features of the circulation in the Gulf of Mexico
is the Loop Current. Especially the shedding of anticyclonic eddies by the
Loop Current is of interest as it supplies heat and freshwater into the
northern Gulf on the one hand and via the Gulf Stream from low latitudes
(subtropics) towards high latitudes on the other hand. For an assessment of
the circulation in the Gulf of Mexico during the Last Glacial Maximum (LGM)
we have reconfigured an existing hierarchy of high-resolution models of the
North Atlantic Ocean (FLAME) with increasing horizontal resolution>
(10,30,100 km), by forcing it with wind stress (taken from PMIPII database)
and lowered sea level (by 67 m and 110 m) representative for the LGM.
Our model results imply a continuous increase in eddy shedding from the LGM
to the Holocence. This increased eddy shedding is predominantly controlled
by the continuous deglacial rise in sea level. Changes in wind stress curl
related to the northward propagation of the ITCZ tend to produce larger
Yucatan and
Florida Strait throughflow but do not play a dominant role in controlling
the eddy shedding, and appear thus of minor importance for the regional
climate in the Gulf of Mexico.
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