Impact of Assimilation of INSAT-3D Sounding Profile on Thunderstorm Prediction over the Eastern India
Abstract
Data assimilation is a method of improving the initial condition of the atmosphere in weather research and forecasting model (WRF). The weather-based INSAT-3D satellite provides the meteorological parameters over India sub-continents at every 30 min about 10 km coverage. Therefore, the present study assesses the impact of assimilation of INSAT-3D atmospheric profiles (temperature and relative humidity profile) on the simulation of severe thunderstorm events during the pre-monsoon season over eastern India. Two different numerical experiments, EXP-CN (without assimilation) and EXP-IN (with assimilation), were conducted using the three-dimensional variational data assimilation technique with WRF. The results indicate that after assimilation, the forecast of the surface fields - 2m-temperature, 2m-relative humidity, and 10m-wind speed has improved at the mature stage (30%, 20°C, and 70 ms-1) compared to EXP-CN. The time, duration, and magnitude of updrafts and downdrafts improved in EXP-IN. After assimilation, out of 11 cases, 5 showed improvement in the thunderstorm duration, and 6 showed improvements in magnitudes in EXP-IN runs. The high value of the critical success index and the lower false alarm ratio for different rainfall thresholds indicate that the assimilation of INSAT-3D data enhances the rainfall prediction skill in thunderstorm study. The results highlight that the INSAT-3D profile data is a viable source of data assimilation for the improved forecast of thunderstorms over eastern India.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.A41E..03K
- Keywords:
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- INSAT-3D;
- WRF-3DVar;
- thunderstorm;
- data assimilation