Retrieval of effective cloud field parameters from radiometric data
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Clouds play a key role in establishing the Earth’s climate. Real cloud fields are very different and very complex in both morphological and microphysical senses. Consequently, the numerical description of the cloud field is a critical task for accurate climate modeling. This study explores the feasibility of retrieving the effective cloud field parameters (namely the cloud aspect ratio and cloud factor) from systematic radiometric measurements at high frequency (measurement is taken every 15 s). Two different procedures are proposed, evaluated, and discussed with respect to both physical and numerical restrictions. None of the procedures is classified as best; therefore, the specific advantages and weaknesses are discussed. It is shown that the relationship between the cloud shade and point cloudiness computed using the estimated cloud field parameters recovers the typical relationship derived from measurements.
This work was partially supported the by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI – UEFISCDI, project number PN-III-P2-2,1-PED-2016-0592, by the CVUT (Czech Technical University in Prague, Czech Republic) institutional resources for research and by the long-term strategic development financing of the Institute of Computer Science (Czech Republic RVO 67985807)
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