First results for diurnal cycles derived from the Earth Radiation Budget Experiment (ERBE) are presented for the combined Earth Radiation Budget Satellite (ERBS) and NOAA-9 spacecraft for April 1985. Regional scale longwave (LW) radiation data are analyzed to determine diurnal variations for the total scene (including clouds) and for clear-sky conditions. The LW diurnal range was found to be greatest for clear desert regions (up to about 70 W · m−2) and smallest for clear oceans (less than 5 W · m−2). Local time of maximum longwave radiation occurs at a wide range of times throughout the day and night over oceans, but generally occurs from noon to early afternoon over land and desert regions.
1 Atmospheric Sciences Division, NASA Langley Research Center, Hampton, VA 23665-5225.
2 Planning Research Corporation, Aerospace Technologies Division, Hampton, VA 23666.
3 ERBE Science Team Principal Investigators: B. R. Barkstrom, ERBE experiment scientist and science team leader, Atmospheric Sciences Division, NASA Langley Research Center; R. D. Cess, State University of New York at Stony Brook; Y. Fouquart, LOA, University of Lille, France; A. Gruber, NOAA/NESDIS; D. L. Hartmann, University of Washington; F. B. House, Drexel University; R. S. Kandel, LMD/CNRS, Palaiseau, France; M. D. King, ERBE project scientist, NASA Goddard Space Flight Center; A. T. Mecherikunnel, NASA Goddard Space Flight Center; A. J. Miller, NOAA/NMC; V. Ramanathan, University of Chicago; J. Coakley, NCAR; E. Raschke, University of Cologne, Germany; G. L. Smith, NASA Langley Research Center; W. L. Smith, University of Wisconsin, Madison; and T. H. Vonder Haar, Colorado State University. A complete listing of ERBE Science Team members is given in Barkstrom (1984).