Relatively warm, nutrient-rich Circumpolar Deep Water (CDW) can be found near the continental shelf break around most of Antarctica. Transport of this water onto continental shelves has important effects on physical and biological processes. For example, CDW exchange provides macro, and perhaps micro, nutrients that can stimulate primary production. Changes in either the temperature or quantity of CDW moving onto the continental shelf have been proposed as a possible mechanism in some areas for increases in the basal melt rate of the floating ice shelves at the edges of the West Antarctic Ice Sheet.

A high-resolution (4 km) regional ocean/sea-ice/ice shelf model of the west Antarctic Peninsula coastal ocean is used to examine the mechanisms of CDW intrusions onto the continental shelf. The model solutions suggest that intrusions are at least partially related to short duration wind events. The effects of possible changes in the winds on the CDW transport and ice shelf basal melt have also been examined. Increases in winds and Antarctic Circumpolar Current transport led to increases in the amount of CDW advected onto the continental shelf. However, these did not necessarily lead to increased CDW flux underneath the nearby ice shelves and the basal melt underneath some of the deeper ice shelves actually decreased with increased wind strength. The different winds also led to differences in the supply of nutrients from the CDW into the upper water column, which could have impacts on surface biogeochemical processes.

After spending several years writing software for flight simulators, Mr. Dinniman went back to school where he received a M.S. in Meteorology from the University of Maryland, College Park, where he first learned about ocean modeling. He then worked for two years at the NASA Goddard Space Flight Center before coming to CCPO in 1999. Mr. Dinniman's research interests are in the area of using computer models to study different bodies of water, ranging from the Pacific Ocean to regional seas around Antarctica to educational models of the Chesapeake Bay and Lake Superior.

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