South India may see early, intense heatwaves thanks to El Nino and global warming

Early heat in southern part of country, even as the north reports colder than normal temperatures
Photo for representation: iStock
Photo for representation: iStock
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The combined impact of global warming and ongoing El Nino conditions in the equatorial Pacific Ocean has started showing heightened temperatures across many regions of the northern hemisphere, including south India. This could lead to an early and intense heatwave in these regions. 

Parts of Africa, southeast Asia, central America, Europe and Asia are also witnessing a rise in temperatures, with some even undergoing heatwaves.

In many of these regions, the heat has arrived much earlier than normal. For Europe, which is already suffering from severe drought conditions, this would be the seventh year of heatwaves in either the spring or summer seasons. Heatwaves have been reported across the continent every year since 2018.  

Daily maximum temperatures in southern India are 4-8 degrees Celsius above normal. The worst affected areas are in western and central Maharashtra, Rayalaseema in Andhra Pradesh and northern Karnataka, according to India Meteorological Department (IMD) data for February 10 and 11, respectively. 

While the heat is rising in southern parts of the country, north India continues to experience below-average temperatures and even coldwaves in some areas — a trend that began in January.

On February 11, large parts of northwest India, such as Uttarakhand, Punjab, parts of Haryana, Himachal Pradesh, northern Rajasthan and western Uttar Pradesh, experienced minimum temperatures 5°C-6°C below normal.

In parts of Himachal Pradesh and Jammu, the deviation from normal was 6-7 degrees Celsius. In Ladakh and Kashmir, the night time temperatures were below normal by 7°C-10°C.

Meanwhile, the IMD predicted above-normal minimum temperatures for most parts of the country.

Down To Earth (DTE) earlier reported about the possibility of early heatwaves in March and April in northwest India, especially in the mountain states that received less than normal snowfall this season. Northwest India experienced the second driest January in the last 124 years, in 2024, according to IMD. 

Maximum temperatures in many parts of India began rising in February for the last two years as well.

In 2023, the temperatures started increasing around mid-February in central, eastern and southern India. However, this time, southern India has been experiencing higher temperatures much earlier — in some cases since the first week of February.

2022 saw heatwaves from March 11, which continued into early June. In 2023 they started on March 3 and continued into the third week of May.

The 2022 heatwaves had resulted in a decrease in the production of wheat and other Rabi crops throughout northwest and central India. In some regions, the decline was as high as 30-40 per cent. The higher day temperatures impacted the crop approaching the reproductive growth period, which is sensitive to temperature.

The heatwaves had also affected the mountainous states of Uttarakhand, Himachal Pradesh and Jammu and Kashmir. Himachal Pradesh experienced heatwaves on 29 days from March 11 to June 6, the third highest in the country, according to a DTE analysis.

The heatwaves in 2023 were tempered by frequent western disturbances that brought down temperatures, brought some relief to northwest India and also decreased their impacts, especially in May.

Western disturbances are extratropical storms that travel to India from the Mediterranean region and bring most of north India’s rainfall and snowfall.

Following a lull during the winter season, western disturbance activity has increased this year, beginning at the end of January. If this trend continues, temperatures may fall over the next few months. But predicting the occurrence of western disturbances is extremely difficult.

With El Nino conditions still ongoing in the equatorial Pacific Ocean and likely to continue till April, temperatures in India and in many other regions in the northern hemisphere may increase drastically.

El Nino is the warmer than normal phase of the El Nino Southern Oscillation phenomenon and is known to increase temperatures across many regions globally.

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