Assessment of Global Cloud Datasets from Satellites: Project and Database Initiated by the GEWEX Radiation Panel

• DOI: 10.1175/bams-d-12-00117.1
• Publication Date: 2013-07-15T14:53:13Z
• Authors: C. J. Stubenrauch; W. B. Rossow; S. Kinne; S. Ackerman; G. Cesana; H. Chepfer; L. Di Girolamo; B. Getzewich; A. Guignard; A. Heidinger; B. C. Maddux; W. P. Menzel; P. Minnis; C. Pearl; S. Platnick; C. Poulsen; J. Riedi; S. Sun-Mack; A. Walther; D. Winker; S. Zeng; G. Zhao
• Keywords: Cirrus; Cloud top; Cloud fraction; Water cycle; Earth's energy budget; Effective radius

Clouds cover about 70% of Earth's surface and play a dominant role in the energy water cycle our planet. Only satellite observations provide continuous survey state atmosphere over entire globe across wide range spatial temporal scales that compose weather climate variability. Satellite cloud data records now exceed more than 25 years; however, must be compiled from different datasets can exhibit systematic biases. Questions therefore arise as to accuracy limitations various sensors retrieval methods. The Global Energy Water Cycle Experiment (GEWEX) Cloud Assessment, initiated 2005 by GEWEX Radiation Panel (GEWEX Data Assessment since 2011), provides first coordinated intercomparison publicly available, standard global products (gridded monthly statistics) retrieved measurements multispectral imagers (some with multiangle view polarization capabilities), IR sounders, lidar. properties under study include amount, height (in terms pressure, temperature, or altitude), thermodynamic phase, radiative bulk microphysical (optical depth emissivity, effective particle radius, path). Differences average properties, especially amount high-level clouds, are mostly explained inherent instrument measurement capability for detecting and/or identifying optically thin cirrus, when overlying low-level clouds. long-term variations these requires consideration many factors. gridded database presented here facilitates further assessments, studies, evaluation models.