A comparison of surface flux products from GEWEX Surface Radiation Budget with ECMWF ERA-40, NCEP/NCAR Reanalysis and CERES SRBAVG

Recently, a global 21.5-year (July 1983 - December 2004) climatology of shortwave (SW) and longwave (LW) radiative flux products has been produced by the NASA/GEWEX Surface Radiation Budget (SRB) project at NASA Langley Research Center. Inputs to the SRB flux algorithms include cloud properties derived from ISCCP pixel level (DX) data, temperature and humidity profiles from Goddard Earth Observing System version 4.0.3 (GEOS-4) long-term meteorological reanalysis and column ozone from TOMS and TOVS archives.

In this presentation, the SRB flux products are compared with similar products available from ECMWF ERA-40, NCEP/NCAR Reanalysis and the CERES SRBAVG for the period from March 2000 through February 2003. Both LW and SW fluxes are compared. When available, select meteorological inputs to the algorithms are also compared and related to the flux differences. Global, zonal, and regional maps of selected months will illustrate the extent of the differences that will be taken as an indication of how the uncertainty in the meteorological fields affects the resulting fluxes. Finally, the fluxes from each of the algorithms will be compared to surface sites of the Baseline Surface Radiation Network (BSRN) and other high quality measurement sites to provide a quantitative comparison between the flux products and input differences. The results will have implications regarding the uncertainties limiting the estimate of surface fluxes.