Five Year Mean Bottom to Surface Temperature Differences in the Northern Gulf of Mexico for 2005 through 2009

These images were created by combining the estimates of the mean bottom to surface temperature differences to produce seasonal representations for winter, spring, summer and fall. Winter includes the months of January, February and March; spring includes the months of April, May and June; summer includes the months of July, August and September; fall includes the months of October, November and December. Estimates of bottom to surface temperature differences (Delta t) were originally obtained from the Naval Research Laboratory at the Stennis Space Center (NRL/SSC). NRL/SSC derived these estimates from a reanalysis of NRL/SSC Intra-Americas Sea Ocean Nowcast/Forecast System (IASNFS). The NRL IASNFS is a 3-dimensional circulation model based on the Navy Coast Model (NCOM) (Ko et al. 2003). The model has a 1/24 degree resolution or about ~5.8 km at the northern Gulf of Mexico and 40 vertical layers. It covers the Gulf of Mexico and Caribbean Sea and uses Navy Global NCOM for the open boundary conditions. IASNFS assimilates satellite altimeter data from GFO, Jason-1, ERS-1/2, EnviSat and TOPEX and sea surface temperature from NOAA AVHRR and MODIS (Ko et al. 2008). The surface forcing includes wind, heat fluxes and sea level air-pressure derived from Navy operational global weather forecast model NOGAPS. The temperature differences were calculated from temperature at surface layer and at bottom layer or to 100 m depth and interpolated onto a 2 minute grid for northern Gulf Coast.