Resolving the diurnal cycle in satellite derived sea surface temperatures and its significance on surface heat fluxes

In an effort to improve spatial and temporal resolution as well as accuracy of global sea surface temperatures for a multitude of applications, a new global field of diurnally varying sea surface temperatures will be generated and examined. A modified version of the original Fairall 1996 (F96) COARE one dimensional bulk model, called Profiles Of Surface Heating 2009 (POSH model) will be used to model the diurnal cycle of SST's. The POSH model simulates diurnal warming based on improvements of solar absorption at the near surface of the ocean, as well as adding the effects of dissipation of heat and momentum and incorporating a non-linear dependence of the temperature distribution on wind speeds (Gentemann et. al 2009). Winds from a multi-satellite gridded wind product and ISCCP radiative fluxes will be used to estimate the diurnal warming on SSTs (dSST) occurring every three hours on a global 1 degree by 1 degree grid. This final product can then be used to compute and examine surface heat fluxes over the global oceans in order indentify the significance of diurnally varying surface heat flux and SST changes. The examination of global plots of diurnal flux changes for different times of year will be used in order to make regional assessments of fluxes based on deviations from the mean SST flux field.

Gentemann, C. L., P. J. Minnett, and B. Ward, 2009: Profiles of Ocean Surface Heating (POSH): a new model of upper ocean diurnal warming. J. Geophys. Res., doi:10.1029/2008JC004825, in press