El Niño behind prolonged heatwaves across India, says IMD study

An IMD study published in MAUSAM has linked prolonged and intense heatwaves across India, including Telangana, to El Niño conditions. Researchers found that strong El Niño events significantly raise temperatures during pre-monsoon months and stressed the need for early Heat Action Plans.

Hyderabad: Wondering why this year’s heatwave across Telangana has been painful and a prolonged affair? Then you are not alone. The heatwaves across the country are becoming longer, stronger, and more frequent, especially during an El Niño year, according to India Meteorological Department (IMD).

A study published by a group of weather researchers from IMD, New Delhi, in MAUSAM, the international scientific journal, has indicated that El Niño years are not only known to trigger deficit rainfall but also are behind prolonged and stronger heatwaves.

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The study is relevant not only for India, since this year is an El Niño year, which is influencing southwest monsoons and turning ordinary summers into extended heat events.

The research paper, titled ‘Impact of El Niño-Southern Oscillation (ENSO) on extreme temperature events over India,’ analysed decades of climate data to paint a stark picture of the subcontinent’s changing weather patterns and its link to El Niño.

It points out that strong El Niño events trigger a significant rise in maximum temperature anomalies, specifically during the crucial pre-monsoon months of April, May, and June.

While the general public often associates El Niño with weak monsoons and its impact on agriculture, the IMD study went a step ahead and threw light on its impact on heatwaves.

El Niño is a natural climate phenomenon where the surface waters in the central and eastern Pacific Ocean become unusually warm. Normally, strong trade winds blow from east to west, pushing warm water toward Asia and allowing cold water to rise up near South America.

During an El Niño year, these trade winds weaken. The shift in ocean temperatures disrupts global weather patterns, alters the path of rainy weather systems away from places like India and Australia, leaving them prone to severe heatwaves and droughts.

According to the study, the geographic impact of this phenomenon is widespread and could be seen in Northwest, Central India, and Peninsular region of India, which stand out as susceptible to extreme heat.

The authors concluded that by predicting the intensity and duration of such heat waves months in advance, local governments can implement targeted Heat Action Plans and save lives through early warnings.