Southern India has become wetter over seven decades, IMD study finds
The area classified as hot semi-arid has nearly halved in the peninsula between 1951-1980 and 1991-2020.
A study by scientists from the India Meteorological Department (IMD) and the Indian Institute of Tropical Meteorology (IITM), Pune, found that Southern India has become wetter over the last seven decades. According to The Hindu, the region classified as having a hot semi-arid climate decreased from approximately 30 per cent to 16 per cent of the peninsula between the periods of 1951-1980 and 1991-2020.
The research, published in the journal MAUSAM, indicates that many hot semi-arid areas in the peninsula have moved into the tropical savannah climate zone. This zone is characterised by higher rainfall and a longer dry season and now covers almost three-fourths of peninsular India, up from about three-fifths in the 1950s.
The study used the Köppen-Geiger climate classification system and IMD rainfall and temperature observations from 1951 to 2020 to map shifts. Researchers noted that most changes in southern India occurred during the 1981-2010 and 1991-2020 periods due to rising rainfall.
In contrast, north-west India has seen the hot semi-arid zone expand from western to eastern Uttar Pradesh as rainfall declined. Additionally, day and night temperatures have risen across the country.
Lead author Ananya Karmakar of IMD Pune said the long-term rainfall increase in the peninsula is a vital factor for water and agricultural planning in Tamil Nadu. The researchers noted that climate zone changes could affect agriculture, specifically regarding sowing periods and suitable crops.
IMD Director-General of Meteorology Mrutyunjay Mohapatra, a co-author, said the department's seasonal forecasts and farmer advisories consider both seasonal variations and long-term climate trends.