Intellectual merit: This project focus on three related activities: first, the reanalysis of a previously unpublished mooring program in the western Gulf of Mexico which included six moorings and AXBT flights; second, analysis of a set of mooring data in Yucatan Channel not previously known widely; and third, incorporation of new results of a mean near-surface flow in the Gulf in collaboration with numerical modelers and SSH analysts. The older experiments were designed and analyzed with the understanding that the Gulf was dominated by the Loop Current and a single large anticylonic ring shed from it. The modern understanding is that the Gulf (and the rest of the ocean) is essentially filled with eddies both small and large and of both signs, as well as with the topographic Rossby waves relevant here. Analyses of older experiments were seriously hampered by the failure to include such possibilities; the present reanalysis will be able to include ideas that have emerged since. The effects of including modern ideas is particularly evident with the data in Yucatan Channel, where the understanding of the flow pattern was changed markedly by the measurements of the joint industry-Navy-Mexico (Deep Star) program there. Incorporating this new mean-flow understanding into both SSH maps and numerical models could be a major step forward, with the potential merit of providing a fundamental improvement for these widely-used scientific tools.
Broader impacts: Historical data currently in unpublished files and master?s theses will be brought out into the open, published literature and will be made available for much wider application. The western Gulf experiment included approximately 350 expendable temperature profiles, which will add a great deal to the existing database for a time period that was seriously under-sampled. Data for the moorings in the Yucatan experiment have not previously been seen at all in the open literature. The heat budget of the upper Gulf of Mexico is important for understanding hurricane models. Improving our understanding of the upper-layer flow and the deep water exchange between the Gulf and the Caribbean Sea is a crucial link in this, as the exchange of cold deep water has to be understood if the heat budget is to be balanced. Finally, a graduate student will be trained and mentored by the principal investigator in conducting independent research.
