Climate crisis link to India’s spring heatwave

A heatwave will sweep large swathes of India over the next 4-5 days, extending from the west and northwest India to the east, weather officials warned on Tuesday, as an unusual heat blast hitting the country since last month seems set to intensify.

Last month, India recorded its warmest March since records were maintained and one of the driest spring seasons, with dry warm winds plunging much of North India into summer temperatures sooner than usual.

Experts said the trends are yet another indicator of the effects of climate crisis, which now puts hundreds of millions of people at greater health risk and trigger productivity loss.

“India’s current heatwave has been made hotter by climate change that is the result of human activities like burning coal and other fossil fuels. This is now the case for every heatwave, everywhere in the world. Until net greenhouse gas emissions end, heatwaves in India and elsewhere will continue to become hotter and more dangerous”, said Friederike Otto, senior lecturer in Climate Science at the Grantham Institute, Imperial College London, according to a statement by the institute. Otto leads the World Weather Attribution group.

This follows freak weather conditions recorded in other parts of the world this year. In March, both of Earth’s polar regions experienced unprecedented simultaneous heat waves – in Antarctica, the average temperature was 4.8°C warmer than average, while in the Arctic, the average was 3.3°C higher than normal, AP reported last month.

For India, experts point to a cyclical weather phenomenon in the Pacific Ocean, the La Nina, which has led to affects that are unusual from the typical influence it is known for.

La Nina, a condition when the sea surface temperature in eastern and central Pacific Ocean is lower than usual, alters a planet-wide wind system and typically leads to a harsher winter, a somewhat more intense summer, and a rainier monsoon in India in the following period. But this year, it seems to have eaten into the spring season entirely, triggering summer-like conditions much sooner.

“In India, the phenomenon is mostly associated with wet and cold winters. Therefore, the current impact of La Niña on the spring and summer season in India is completely unexpected,” said Raghu Murtugudde, a climate scientist at the University of Maryland, according to a statement by the Centre for Science and Environment (CSE).

The early heat waves of 2022 started on March 11 and have impacted 15 Indian states and Union territories (as of April 24), according to data from IMD, which was analysed by CSE. Rajasthan and Madhya Pradesh have suffered the most among the states, with 25 heat wave and severe heat wave days each during this period.

“It is extremely unusual… Heatwaves started very early this year in March and over a large region. Now again severe heatwaves are likely over large areas in north and east India during the next two weeks,” said M Rajeevan, former secretary, ministry of earth sciences. “These cannot be due to local meteorological features, but linked to large-scale atmospheric and oceanic conditions, which require analysis,” he added.

In a silver lining, however, Rajeevan added that the monsoon may not be affected. “Thankfully, this year El Nino (which saps the monsoon) is unlikely to impact us. This year either La Nina or ENSO neutral conditions are likely to persist, which will help the monsoon.”

ENSO neutral conditions refer to those periods in which neither El Nino nor La Nina is present. These weather phenomena in the Pacific Ocean affects ambient temperatures and rainfall over South Asia.

La Nina conditions are likely to persist till mid-monsoon, according to IMD. “La Nina continues in the tropical Pacific, with the current forecast favouring the continuation of La Nina through the summer, with a slightly lower chance into the fall,” the research wing of National Oceanic and Atmospheric Administration tweeted on Sunday.

A second reason why the unusual affect may be happening is that the La Nina-triggered wind patterns lead to clear skies and what is known as an anti-cyclone system. “This is causing incursion of dry, very hot winds from the western region,” said DS Pai, director at the Kottayam-based Institute for Climate Change Studies.

Such weather is already stressing India in several ways. The country is grappling with a power crisis, with surging demand triggering a clamour for coal to feed thermal power plants. On Monday, India breached its all-time peak power demand of 201.066 GW, surpassing a past record that was set on July 7 last year, which was much further into the typical summer season.

The early hot spell has also hit wheat yield, one of the mainstay winter crops harvested in spring. Traders and analysts have in recent days said it is clear from procurement trends that the country will have a smaller crop this year than previously predicted.

This could further fuel food inflation, adding to a price rise pressure that has now persisted for several months.

The weather is also a risk to public health. More frequent hot days and intense heat-waves increase heat-related deaths in Asia, the Asia factsheet of Intergovernmental Panel on Climate Change’s “Climate Change 2022: Impacts, Adaptation and Vulnerability” report said in February.

“Extreme heat puts additional load on the circulatory system which has to do additional work to cool the body via perspiration. This may lead to dehydration and increased metabolism. Excess heat may be linked to increase or exacerbation of complications of diabetes due to dehydration and increased metabolism. Infant mortality will rise because children are not able to control their body temperature well,” said Dilip Malvankar, director, Indian Institute of Public Health, Gujarat had said in February.

But the larger picture is clear: the climate crisis has likely begun leading to affects that are unpredictable.

“The recent high temperatures in India were made more likely by climate change. Before human activities increased global temperatures, we would have seen the heat that hit India earlier this month around once in 50 years. But now it is a much more common event – we can expect such high temperatures about once in every four years. And until net emissions are halted, it will continue to become even more common,” said Mariam Zachariah, research associate at the Grantham Institute, Imperial College London, in a statement to Climate Trends, a climate communications organisation.