Cloud optical depths and TOA fluxes: Comparison between satellite and surface retrievals from multiple platforms

Performances of two cloud property retrieval schemes are assessed by compar ison with each other. The study is limited to liquid phase clouds. Two para meters are assessed: cloud optical depth in the visible band and broadband shortwave (SW) flux at the top-of-atmosphere (TOA). Retrievals are based on look-up tables for a variety of conditions using an adding-doubling code c oupled with LOWTRAN-7 transmittance models. Comparisons of cloud optical de pths retrieved from sound measurements with those from ISCCP DX data agree better than previously reported comparisons with the original ISCCP CX data Likewise, good agreement is obtained between retrieved and inferred TOA SW fluxes. Differences fall within uncertainties of input parameters, as well as shortcomings in the use of a plane-parallel radiative transfer model an d in the inversion schemes themselves.