HEATWAVE OCCURRENCES INCREASES IN INDIA

HEATWAVE OCCURRENCES INCREASES IN INDIA

Context:

A recent analysis by the Mahamana Center of Excellence in Climate Change Research (MCECCR) at Banaras Hindu University (BHU), in collaboration with the Department of Science and Technology and the Ministry of Earth Sciences, has found a spatial shift of heatwaves in India, with this weather event now occurring in new regions in the country.

What are Heatwaves?

• Heatwaves are described as prolonged episodes of extreme temperature over any region.
• In addition to temperature, humidity is an important parameter that is considered to declare heat-related stress.

Key Findings of the Study:

• The MCECCR study looked at pre-rainy (March-May) and early summer (June-July) annual temperature data from the India Meteorological Department, covering 65 years from 1951-2016, a monthly survey, monthly, seasonal, decadal and long-term trends in the country heatwaves.
• It found a warming pattern above the northwest and southern India, while the cooling phase continued in the northeast and southwest parts of the country.
• The study has shown a “spatio-temporal shift” when heatwave events occur, with a sharp increasing trend in three prominent heatwave prone regions — northwestern, central, and south-central India, with the highest being in west Madhya Pradesh (0.80 events/year).
• Interestingly, the study has also found a significant decline in heatwaves in the eastern region, namely Gangetic West Bengal (-0.13events / year).