The authors wish to acknowledge the contributions from several colleagues. Mr. Richard Frey studied the relative contributions of cloud fraction or cloud emissivity with AVHRR and HIRS data. Mr. Harold Woolf contributed many hours toward maintaining reliable access to the HIRS data used in this study; Mr. Geary Callan acquired the necessary ancillary data to complete the dataset for cloud studies. Ms. Kathy Strabala compiled many of the cloud datasets for investigating geographical and temporal trends and contributed to many lively discussions of the results. This work was supported by the National Environmental Satellite Data and Information Service of the National Oceanic and Atmospheric Administration (NOAA/NESDIS), which provided the HIRS data and support under Contract 50-WCNE-8-06058. Additional support came from Grants N00014-85-K-0581 and N00014-87-K-0436 from the Office of Naval Research; Grants NAG1-553 and NAG1-1830 and Contract NAS5-31367 from the National Aeronautics and Space Administration; Grant ATM-8703966 from the National Science Foundation; and Grant F19628-91-K-0007 from the United States Air Force Geophysics Laboratory.
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