Outgoing longwave radiation and its diurnal variations from combined Earth Radiation Budget Experiment and Meteosat observations 2. Using Meteosat data to determine the longwave diurnal cycle

For April and July 1985, applying the narrow to broadband conversion of part 1 to Meteosat observations obtained at 3-hour intervals (ISCCP B2 data), we determine the monthly mean radiant exitance as well as the mean diurnal variation, over 2.5° x 2.5° latitude-longitude regions of tropical Africa and the neighboring Atlantic Ocean. We compare these determinations with those obtained directly from the ERBS and NOAA 9 Earth Radiation Budget Experiment (ERBE) data for this month, for which the time sampling is sparser and not so uniform. We consider the possible improvements in diurnal interpolation procedures, but note that there is no general way to remove bias resulting from inadequate time sampling. -from Authors