IMD study finds northwest India growing drier and south peninsula wetter over seven decades

Key facts

• A new study by the India Meteorological Department (IMD) and Indian Institute of Tropical Meteorology, published in IMD's peer-reviewed journal Mausam, finds northwest India has turned drier and the south peninsula wetter over the past seven decades.
• In northwest India, the hot semi-arid zone expanded from about a quarter of the region's area in 1951-1980 to a third in 1991-2020, while the temperate zone shrank from about a quarter to less than a fifth, shifting roughly 7% of the region into the drier zone.
• The dry climate zone, which once ended in western Uttar Pradesh, has extended eastward into the state, and scientists warn the change could affect paddy cultivation in the north.
• In peninsular India, the hot semi-arid zone shrank from about 30% of the region to 16%, with most of that land shifting to the tropical savannah zone, which now covers three-quarters of the peninsula due to rising rainfall over southern India.
• Marathwada and west Vidarbha in Maharashtra moved into the hot semi-arid zone, while the tropical monsoon zone extended along the Konkan coast, coastal Karnataka and Kerala.
• The study compared India's climate map decade by decade from 1951 to 2020; its lead author Ananya Karmakar said the clearest change was the hot, dry zone pushing east into Uttar Pradesh, a key farming region where sowing and harvesting timings need close watching.