Derivation of improved surface and TOA broadband fluxes using CERES-derived narrowband-to-broadband coefficients

Satellites can provide widescale coverage of a number of climatically important radiative parameters, including broadband shortwave and longwave fluxes at TOA (Top of Atmosphere) and surface. GOES (Geostationary Operational Environmental Satellite) satellites provide the capability of measuring narrowband fluxes at 15-minute to hourly intervals, but in order to be climatically useful these parameters must be converted to broadband fluxes. Narrowband-to-broadband flux conversion can be facilitated by making comparisons of the broadband fluxes from CERES (Clouds and the Earth's Radiant Energy Budget) to the narrowband fluxes available from the GOES satellites. The VISST (Visible Infrared Solar Split-Window Technique) satellite retrieval algorithm facilitates derivation of broadband fluxes from GOES satellite data, but their accuracy is dependent in part on the validity of the narrowband-to-broadband conversion coefficients. These coefficients are currently based on 1986 ERBE (Earth's Radiant Energy Budget)-GOES6 comparisons. The CERES (Clouds and the Earth's Radiant Energy Budget) has much improved ADMs (Angular Distribution Models) and resolution compared to ERBE, so new narrowband-to-broadband coefficients derived from CERES and the GOES suite are expected to yield better accuracy. New coefficients are derived for the Southern Great Plains area (SGP) using GOES-8 and GOES-10 data from 2000-2005, and the Tropical Western Pacific (TWP) using GOES-9 for 2004-2005.

Validation of the VISST-derived TOA fluxes using the new coefficients is performed. Additionally, improved TOA shortwave fluxes improve the shortwave surface fluxes, also calculated using the VISST products. The impacts of the improved narrowband-to-broadband coefficients on derived surface fluxes, using the Li-Leighton method, Langley Parameterization Shortwave Algorithm and Langley Parameterization Longwave Algorithm, are examined.