GEWEX SRB Release 4: Full Timeseries Analysis

The NASA/GEWEX Surface Radiation Budget (SRB) project produces 3-hrly shortwave and longwave surface and top of atmosphere radiative fluxes for the 1983-near present time period. The new Release 4 uses the newly recalibrated and processed ISCCP HXS product as its primary input for cloud and radiance data, replacing ISCCP DX with a ninefold increase in pixel count (10km instead of 30km). This version of SRB retains a 1-degree resolution; future releases may go to 0.5-degree. ISCCP also provides an atmospheric temperature and moisture dataset known as nnHIRS which we use here.

In addition to the input data improvements, several important algorithm improvements have been made since Release 3. These include recalculated SW atmospheric transmissivities and reflectivities yielding a less transmissive atmosphere. The calculations also include variable aerosol composition, allowing for the use of a detailed aerosol history from the Max Planck Institut Aerosol Climatology (MAC). Ocean albedo and snow/ice albedo are also improved from Release 3. Total solar irradiance is now variable, averaging 1361 Wm^-2.

Here we analyze the new SW and LW SRB datasets, comparing them to the previous Release 3, BSRN and PMEL surface measurements, and ERBE and CERES satellite datasets.