Surface radiation budget data are presented for the midseasonal months of July and October of 1983 and January and April of 1984. These data allow examination for the first time of geographical and seasonal variations of the entire surface radiation budget from pole to pole. The latest flux estimation techniques have been used along with data from the International Satellite Cloud Climatology Project (ISCCP) and the Earth Radiation Budget Experiment (ERBE). Regional, zonal, and hemispheric distributions of the downward and net components of both shortwave and longwave fluxes and of the net total surface fluxes are determined. Seasonal flux variation per region, expressed as flux range, is illustrated for these components also. The estimated fluxes appear to be accurate to about 16 W m−2 on a global average, based on sensitivity analyses and comparisons with ground data. An analysis of flux errors showed that most of the error was attributable to errors in input data.

Shortwave radiative fluxes that reach the earth's surface are key factors that influence atmospheric and oceanic circulations as well as surface climate. Yet, information on these fluxes is meager. Surface site data are generally available from only a limited number of observing stations over land. Much less is known about the largescale variability of the shortwave radiative fluxes over the oceans, which cover most of the globe. Recognizing the need to produce global-scale fields of such fluxes for use in climate research, the World Climate Research Program has initiated activities that led to the establishment of the Surface Radiation Budget Climatology Project with the ultimate goal to determine various components of the surface radiation budget from satellite data. In this paper, the first global products that resulted from this activity are described. Monthly and daily data on a 280-km grid scale are available. Samples of climate parameters obtainable from the dataset are presented. Emphasis is given to validation and limitations of the results. For most of the globe, satellite estimates have bias values between ±20 W rrr 2 and rms values are around 25 W nrr 2. There are specific regions with much larger uncertainties however.

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Abstract. Analytic expressions for the bidirectional reflectance functions are formulated and fit to the Earth Radiation Budget Experiment (ERBE) operational models, which were developed using Nimbus 7 ERB data. The analytic bidirectional reflectance distribution functions (BRDFs) are based on theoretical considerations and are functions of viewing geometry and scene type. The models consist of a Rayleigh scattering term and a term for scattering due to clouds and surface. The darkness of the ocean permits the empirical determination of the Rayleigh component of scattering from the atmosphere. The models have the advantage that they are smooth in terms of view and solar zenith angles and relative solar azimuth angle and satisfy reciprocity. Results are presented for the ERBE scene types. The analytic functions closely model the reflectances in the forward scatter direction, but in the backscatter direction, the analytic models are slightly more limb brightened than the ERBE operational models. The model was also fit to the Dlhopolsky/Cess BRDF for clear ocean, which provides a finer angular resolution than the ERBE BRDFs. The results of this study provide a set of BRDFs for ERBE scene types in terms of a set of simple equations and few coefficients for each scene type. These