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.