A global 9-yr biophysical land surface dataset from NOAA AVHRR data

Global, monthly, 1 degrees by 1 degrees biophysical land surface datasets f or 1982-90 were derived from data collected by the Advanced Very High Resol ution Radiometer (AVHRR) on board the NOAA-7, -9, and -11 satellites. The A VHRR data are adjusted for sensor degradation, volcanic aerosol effects, cl oud contamination, short-term atmospheric effects (e.g., water vapor and ae rosol effects less than or equal to 2 months), solar zenith angle variation s, and missing data. Interannual variation in the data is more realistic as a result. The following biophysical parameters are estimated: fraction of photosynthetically active radiation absorbed by vegetation, vegetation cove r fraction, leaf area index, and fraction of green leaves. Biophysical retr ieval algorithms are tested and updated with data from intensive remote sen sing experiments. The multiyear vegetation datasets are consistent spatiall y and temporally and are useful for studying spatial, seasonal, and interan nual variability in the biosphere related to the hydrological cycle, the en ergy balance, and biogeochemical cycles. The biophysical data are distribut ed via the Internet by the Goddard Distributed Active Archive Center as a p recursor to the International Satellite Land Surface Climatology Project (I SLSCP) Initiative II. Release of more extensive, higher-resolution datasets (0.25 degrees by 0.25 degrees) over longer time periods (1982-97/98) is pl anned for ISLSCP Initiative II.