Observational evidence of the land cover effect on shallow cumulus clouds over the U.S. Southern Great Plains

Abstract:

The continental shallow cumulus clouds (ShCu) are tightly coupled with the land surface. The land covers (e.g forest, grassland, crops) with different albedo, surface roughness, soil moisture content and leaf area index, can impact the surface energy balance and the turbulent transfer of momentum, heat and water vapor, therefore the formation of clouds. However, the observational evidence of such impact is very limited. In this study, we use the cloud observation from stereo cameras at SGP, the reflectance data from Geostationary Operational Environmental Satellite (GOES-R), and high-res land cover data to study the coupling between land surface and shallow cumulus. This study will answer two questions (1) Are there any preferences of the ShCu occurrences over different homogeneous land covers? (2) Are there any differences of ShCu occurrences around the heterogeneous land cover boundaries? We find that during the summertime, ShCu prefer to occur more over forest than over grassland and more over boundaries between different land covers than over a homogeneous land cover. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. LLNL-ABS-812835.