A study of vertical liquid water profiles of clouds from in-situ measurements

Vertical profiles of liquid water in supercooled frontal stratiform clouds have been studied to estimate liquid water path. The vertical soundings of the liquid clouds were obtained using the National Research Council of Canada Convair-580 equipped by Environment Canada for cloud microphysical measurements. The data were collected during five flight campaigns (CFDE 1, CFDE 3, AIRS 1, AIRS 1.5 and AIRS 2). In total 584 vertical LWC profiles were analyzed. A statistical summary has been prepared from the profiles of the liquid water path, liquid water content, temperature, and cloud depths. Statistical distributions of cloud depths, liquid water paths, and maximum liquid water content are presented. It was found that for clouds with the cloud depth over 500 meters the average liquid water content does not depend on the cloud depth and it stays constant. The cumulative distribution of liquid water path from in-situ observations was wound in a good agreement with ground based microwave radiometer measurements. Based on the analysis of the vertical profiles it is hypothesized that the characteristic vertical scale of the circulation cells in the frontal clouds is of the order 300-500 meters. The obtained results can be utilized for validation of GCM and weather models.