Comparison of airborne in-situ, airborne radar-lidar, and spaceborne radar-lidar retrievals of polar ice cloud properties sampled during the POLARCAT campaign
International audience This study illustrates the high potential of RALI, the French airborne radar-lidar instrument, for studying cloud processes and evaluating satellite products when we have satellite overpasses. We demonstrate, for an Arctic Nimbostratus ice cloud collected on 1 April 2008 durin...
Published in: | Journal of Atmospheric and Oceanic Technology |
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Main Authors: | , , , , , , , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2013
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Subjects: | |
Online Access: | https://hal.science/hal-00730535 https://hal.science/hal-00730535/document https://hal.science/hal-00730535/file/%255B15200426%2520-%2520Journal%2520of%2520Atmospheric%25.pdf https://doi.org/10.1175/JTECH-D-11-00200.1 |
Summary: | International audience This study illustrates the high potential of RALI, the French airborne radar-lidar instrument, for studying cloud processes and evaluating satellite products when we have satellite overpasses. We demonstrate, for an Arctic Nimbostratus ice cloud collected on 1 April 2008 during the POLARCAT campaign, the capability of this synergistic instrument to retrieve cloud properties and to characterize the cloud phase at scales smaller than a kilometer which is crucial for cloud process analysis. A variational approach, which combines radar and lidar, is used to retrieve IWC, extinction and effective radius. We show that the combination of radar and lidar provides better retrievals than stand-alone retrievals, and that in general the radar overestimates and the lidar underestimates IWC. As the sampled ice cloud was simultaneously observed by CloudSat and CALIPSO satellites, we show a new way to assess satellite cloud products by combining in-situ and active remote sensing measurements. It was then possible to compare RALI to three satellite ice cloud products: CloudSat, CALIPSO and DARDAR. |
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