Gala Wind

Comparison of the MODIS Collection 5 Multilayer Cloud Detection Product with CALIPSO

CALIPSO, launched in June 2006, provides global active remote sensing measurements of clouds and aerosols that can be used for validation of a variety of passive imager retrievals derived from instruments flying on the Aqua spacecraft and other A‐Train platforms. The most recent processing effort for the MODIS Atmosphere Team, referred to as the Collection 5 scream, includes a research‐level multilayer cloud detection algorithm that uses both thermodynamic phase information derived from a combination of solar and thermal emission bands to discriminate layers of different phases, as well as true layer separation discrimination using a moderately absorbing water vapor band. The multilayer detection algorithm is designed to provide a means of assessing the applicability of 1D cloud models used in the MODIS cloud optical and microphysical product retrieval, which are generated at a 1 km resolution. Using pixel‐level collocations of MODIS Aqua, CALIOP, we investigate the global performance of multilayer cloud ...

Comparison of Cloud Top Altitudes from Passive and Active Remote Sensors onboard ER‐2 during TC4

Cloud altitude is one of the key properties for the Earth radiation budget. There still exist large uncertainties on cloud altitude as well as optical and microphysical properties for high altitude clouds, in particular. Targeting the high altitude clouds around tropical tropopause transition layer (TTL), the Tropical Composition, Clouds and Climate Coupling (TC4) Experiment was carried out, based on Costa Rica during July and August 2007. In this campaign, NASA’s high altitude airplane, ER‐2, made remote sensing observation, and we obtained precious data with both passive and active remote sensors, such as Imager, Sounder, LIDAR, Radar, and so on. In this study, we compare cloud top altitudes using colocated datasets with Imager, LIDAR, and Sounder onboard the high altitude airplane. We have preliminary results, which are generally consistent with the former field campaign based on Hawaii during February and March 2003. We discuss the consistency between IR sounding and LIDAR backscattering measurements,...

Mulitlayer Cloud Detection in the MODIS Collection 5 Cloud Product

Multilayer cloud detection using, in part, a water vapor absorption band at 0.94 µm has been implemented in the recent MODIS Collection 5 processing stream. Evaluation with active sensor(s) will be discussed.