Observational Study of Nisarg Cyclone Winds using Phased Array Doppler Sodar at Atigre, Kolhapur, India

Abstract One of the most important parameters in meteorology is the mean wind profile in the tropical cyclone boundary layer. The signature of the Nisarg cyclone is reported in the Phased Array Doppler Sound Detection and Ranging (SODAR) data installed at the Center for Space and Atmospheric Science (CSAS), Sanjay Ghodawat University, Kolhapur (16.74° N, 74.37° E; near India's western coast). The vertical profile of wind speed and wind direction measured from the sodar system clearly reveals the signature of Nisarg cyclone during 2- 3 June 2020. Our analysis revealed that, the maximum mean wind speed was 17 m/s on 3rd June 2020 at 10:00 IST. It also shows the change in the wind direction from southwest to southeast on 2nd June 2020 and 3rd June 2020. Daily high-resolution reanalysis in the domain, 0-25°N, 65-110°E, during the period from 31st May-5th June 2020 shown the variation in atmospheric pressure of the Nisarg cyclone from 1000 to 1008 hPa, sea surface tremperature (SST) between 30 and 31°C, outgoing longwave radiation (OLR) varied between 100 and 240 Wm−2, wind speed between 3 and 15 m/s and low values of vertical wind shear (VWS) was observed to the north of the track Nisarg. These findings could aid in better understanding and forecasting in this region. The present results are initial measurements of sodar system.