Some Aspects of Ocean-Atmosphere Interactions and Associated with Land-falling Hurricane Katrina Over the Gulf of Mexico

Previous studies by Reddy etal. (2006) have indicated strong interactions of ocean and atmosphere through surface fluxes (heat, momentum and latent heat) associated with the formation and development of tropical cyclone/hurricane activity over the warm pool area of Gulf of Mexico. We extend these investigations to study the ocean-atmosphere interactions and associated hurricane Katrina using satellite data and numerical models. Hurricane Katrina began to strengthen reaching Category 5 on 28th August, 2005 and it's winds reached peak intensity of 175 mph and the pressure fell to 902 MB, making landfall in Plaquemines Parish, Louisiana just South of Buras on 29th August 2005. Weather Research Forecast (WRF) Mesoscale Model simulations are used for better understanding of the structure and dynamics of hurricane Katrina activity and compared model output with observations. The model is run on a doubly nested domain centered over the central Gulf of Mexico, with grid spacing of 90 km and 30 km for 6 hr periods, from August 28th to August 30th. The model is capable of simulating surface features, intensity change and track associated with hurricane Katrina. The study suggested strong heat and latent heat fluxes with heaviest rainfalls as Katrina changes its intensity while making landfall. We are extending these results to compare with other models including NMM and HWRF models.