MOISTURE DETECTION ABOVE CONVECTIVE STORMS UTILIZING THE METHOD OF BRIGHTNESS TEMPERATURE DIFFERENCES BETWEEN WATER VAPOR AND IR WINDOW BANDS, BASED ON 2008 MSG RAPID SCAN SERVICE DATA
Abstract
The BTD method based on the Brightness Temperature Difference between WV and IR window bands has been used in previous studies to document the presence of water vapor above the tops of convective storms. This lower stratospheric moisture (LSM) can either be advected above the storms from remote locations, or injected into the lower stratosphere by the storm itself.
Previous studies either addressed cases observed by polar orbiting satellites (thus being only "snapshots"), or presented individual cases documented by MSG/SEVIRI 15-min. data. The present study focuses on this topic using a large dataset of cases collected during the 2008 season, documenting the hypothesized above-storm-LSM by means of MSG Rapid Scan Service 5-min. data.
Besides the detection and statistics of LSM based on this dataset, we will also try to determine if any particular storm type tends to generate enhanced LSM, including the life cycle of these storms, and at what time the storm becomes the most efficient at generating LSM.