Extreme heat in April made worse by climate crisis: Study
In the larger South Asia region, an extremely warm April is a somewhat rarer event, with a 3% probability of happening in a given year
Extreme heat events in April over large parts of South Asia were made 45 times more likely and 0.85°C hotter by the climate crisis, an analysis by World Weather Attribution (WWA), a global team of climate scientists said on Tuesday.
These results align with WWA’s previous studies in 2022 and 2023 focused on the South Asia region which found that climate change made extreme heat in March and April about 30 times more likely and at least 1°C hotter.
In the larger South Asia region, an extremely warm April is a somewhat rarer event, with a 3% probability of happening in a given year – but it has become more common in recent years.
Two previous WWA studies focused on extreme heat events in the region: the 2022 spring heat wave in India and Pakistan and the 2023 humid heatwave that hit India, Bangladesh, Lao PDR and Thailand. For this year’s analysis, WWA considered the area covering India, Bangladesh, Myanmar, Lao PDR, Vietnam, Thailand and Cambodia.
“In South Asia, there has been a succession of hot spring periods in recent years including multiple direct attribution studies... these studies are commensurate with an extensive literature documenting observed and projected increases in heat extremes in the region due to anthropogenic influence,” the analysis said.
“In South Asia, a region that we have studied twice in the last two years, our analysis was simpler and based only on observations. Similarly to what we found in previous studies, we observe a strong climate change signal in the 2024 April mean temperature. We find that these extreme temperatures are now about 45 times more likely and 0.85ºC hotter,” the analysis added.
The team used historical temperature data and models to analyse how current warming of around 1.2°C over pre-industrial levels is influencing these events.
The WWA scientists suspect there may have been thousands of deaths during the period, but which went grossly underreported. There were at least 28 deaths in Bangladesh, five in India and three in Gaza during April, while surges in heat deaths have also been reported in Thailand and the Philippines this year.
“These are only preliminary figures and because heat-related deaths are notoriously underreported, it is likely there were hundreds or possibly thousands of other heat-related deaths in Asia during April. The heat also led to crop failure, loss of livestock, water shortages, mass die-off of fish, widespread school closures, and the heat has been linked to low voter turnout in Kerala, India,” WWA said.
Extreme heat has forced thousands of schools to close in South and Southeast Asia. These regions have previously also incurred school lockdowns during Covid-19, increasing the education gap faced by children from low-income families, enhancing the risk of dropouts, and negatively impacts the development of human capital, the scientists said in a statement.
Further, heat impacts certain groups like construction workers, transport drivers, farmers, fishermen etc disproportionately. Existing heatwave action plans and strategies are challenged by rapidly growing cities, increase in informal settlements and exposed populations, rise in energy demand. Many cities are implementing solutions such as cool roofs, nature based infrastructure design, better building codes, there is limited focus on retrofitting and upgrading of existing buildings and settlements, they added.
WWA scientists said India has comprehensive heat action plans in place, yet to protect some of the most vulnerable people, these must be expanded with mandatory regulations, such as scheduled rest breaks at workplaces with exposed workers, fixed work hours, and rest-shade-rehydrate programs (RSH) etc.
HT reported on May 4, that heatwave to severe heatwave conditions have been prevailing over Odisha since April 15, Gangetic West Bengal since April 17, Jharkhand and sub-Himalayan West Bengal, Rayalaseema since April 24 and Bihar since April 26 and similar temperatures were recorded across South Asia including Bangladesh, Myanmar and Philippines.
“The lingering heat from El Nino (that is now dissipating) riding on the background global warming during the peak of summer makes it hotter than usual,” Roxy Mathew Koll, climate scientist at Indian Institute of Tropical Meteorology said on May 4.
“Climate change is bringing more days with potentially deadly temperatures to Asia every year. This result is unsurprising, but important for highlighting the dangers of extreme heat in Asia. Unless the world takes massive, unprecedented steps to reduce emissions and keep warming to 1.5 degree C, extreme heat will lead to even greater suffering in Asia,” said Mariam Zachariah, Researcher at the Grantham Institute – Climate Change and the Environment, Imperial College London in a statement.