Evaluation of convective instability of the atmosphere in the cases with squalls, tornadoes and large hail events according to satellite observations and ERA5 reanalysis data
A.N. Shikhov1,2, A.V. Chemokulsky2,3, A.A. Sprygin2,4, Yu.I. Yarinich2,5
a:2:{s:4:"TYPE";s:4:"HTML";s:4:"TEXT";s:449:"1Perm State National Research University, Perm, Russia 2A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences, Moscow, Russia 3Institute of Geography RAS, Moscow, Russia 4Russian Federal Service on Hydrometeorology and Environmental Monitoring Research and Production Association «Typhoon», Obninsk, Russia 5Lomonosov Moscow State University, Moscow, Russia";}
Keywords: convective hazardous weather event, squall, tornadoe, MODIS satellite data, convective instability, precipitable water vapor, ERA5 reanalysis
Abstract
We consider the usefulness of satellite data to estimate atmospheric instability and precipitable water vapor for the cases with severe convective events occurred over the European Russia and the Ural region. The initial sample includes 305 squalls, tornado, and large hail events. We evaluated the values of the instability parameter Lifted Index (LI) and precipitable water vapor (PW) using MODIS Atmospheric Profile Product data as well as the ERA5 reanalysis data. It was found that the median values of LI and PW according to the MODIS and ERA5 data are rather close, while the extreme values substantially differ. Local areas with very strong instability and high PW were identified from MODIS data, but not detected according to the reanalysis data. We found major limitations of the MODIS data associated with rather low frequency of imagery and the lack of information on the instability parameters for cloudy pixels. In particular, it reduced the sample size from 305 to 95 cases.
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