Evaluation of INSAT-3DR sounder derived wind index using radiosonde observation over India

Rapid advancements in the field of forecasting demand in-depth study across various climate fields, including wind-derived products. The wind index is a highly valuable parameter that exhibits significant variability and intermittence across various timescales due to its dependence on weather conditions. Therefore, accurate wind index observation is acknowledged as a vital contribution to trustworthy large-scale Thunderstorm forecasts. Nevertheless, the satellite-derived wind index observations are often associated with errors and require extensive evaluation before their use in operational forecasts. The present study aims to assess the wind index retrieved from the Infrared (IR) sounder data from the Indian National Satellite System (INSAT)-3DR using in-situ radiosonde data. It was found that the results closely resemble the unfavourable skew of the satellite data. The assessment shown in the present study is carried out for years 2020, 2021 and 2022 or different stations spread over vast India. Furthermore, this paper emphasizes the Wind Index accuracy for helicopter operation. However, wind index information is derived by satellite but always missing by Radiosonde. The proposed method is applied to the estimating Radiosonde wind index. This study mainly focuses on calculating wind index from different radiosonde parameters and then validating INSAT 3DR with Radiosonde WI.