Increasing pre-monsoon rain days over four stations of Kerala, India

• Published in: Acta geophysica Vol. 70; no. 2; pp. 963 - 978
• Main Authors: Umakanth, Nandivada, Kalyan, S. S. S., Satyanarayana, Gubbala China, Gogineni, Rajesh, Nagarjuna, Ayachithula, Naveen, Ramisetti, Rao, Kokkerapati Ramachandra, Rao, Myla Chimpiri
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-04-2022; Springer Nature B.V
• Subjects: Convective available potential energy; Daily rainfall; Dew point; Dew point depression; Earth and Environmental Science; Earth Sciences; Geophysics/Geodesy; Geotechnical Engineering & Applied Earth Sciences; Global precipitation; Humidity; Humidity indexes; Moisture effects; Monsoon rainfall; Monsoons; Potential energy; Precipitable water; Precipitation; Precipitation patterns; Rain; Rainfall; Relative humidity; Research Article - Atmospheric & Space Sciences; Structural Geology; Weather; Weather conditions; Wind; Wind direction; Kerala India; India; Convective system; Precipitation; Dew point depression; Analysis
• DOI: 10.1007/s11600-022-00742-6
• EISSN: 1895-7455
• ISSN: 1895-7455; 1895-6572

The climate of India varies greatly by region, as seen by wind patterns, temperature and rainfall, seasonal rhythms and the degree of wetness or dryness. During the several seasons, the weather conditions change. Changes in meteorological factors (temperature, pressure, wind direction and velocity, humidity and precipitation, etc.) cause these changes. The pre-monsoon season (PRMS) comprises of March, April and May months. The precipitation patterns observed in PRMS are crucial because it affects a variety of crop-related operations across the country. The lifting index (LI), K index (KI), total totals index (TTI), humidity index (HI), improved k index, improved total totals index, total precipitable water (TPW) and convective available potential energy (CAPE) are studied at four locations in Kerala during PRMS. These variables were examined on rain day (RD)’s and no rain day (NRD)’s. The four stations we chose for our investigation were Thiruvananthapuram, Kochi, Alappuzha and Kannur. The GPM IMERG (Integrated Multi-satellite Retrievals for Global Precipitation Measurement) daily rainfall datasets have been utilized for this analysis. Fifth-generation ECMWF atmospheric reanalysis (ERA5) daily data for the PRMS of 2021 were used to measure all rainfall-related variables. During PRMS, all metrics clearly distinguished the RD and NRD. The rise in relative humidity and observations of dew point depression indicates that there is enough moisture for convective rain. In May, there were more negative VV values than in April.