Warm winds have been blowing in from the Arabian Sea towards northwest India, a consequence of the record-breaking warmth that the sea has absorbed in the past couple of years
On May 29, 2024, India Meteorological Department’s (IMD) Mungeshpur automated weather station in north Delhi recorded a hard to believe temperature of 52.9°C. If confirmed, this would be the highest temperature ever recorded in India. As soon as the news broke out, it spread like wildfire.
The IMD released a statement on the evening of May 29, explaining that the anomalous temperature “could be due to error in the sensor or the local factor”. The weather agency is currently investigating the event.
The rest of Delhi and the National Capital Region (NCR) recorded temperatures between 45.2°C and 49.1°C. At many of the weather stations, the recorded temperatures were actually a bit lower as compared to May 28 and it even rained in the evening of May 29. IMD cites these observations for highlighting the unlikelihood of the temperature record.
Whether the record-breaking temperature in Mungeshpur is confirmed or not, north, northwest and central India have been under an intense heatwave spell for the past 15 days or so.
Gujarat and Rajasthan are the worst-affected states, having suffered from 12 and 11 heatwave days respectively between May 16 and May 26. More than 60 people have died in Rajasthan due to the intense heat, according to media reports.
There have been two spells of heatwaves in India in May. The first was from May 1 to May 7 when Odisha, Gangetic West Bengal, the southeast Peninsular region and interior parts of Karnataka experienced heatwaves on 5-7 days, according to data from the IMD.
The second spell began on May 16 and is still ongoing. During this time, Rajasthan, Gujarat, Delhi-NCR, south Haryana, southwest Uttar Pradesh, Punjab and Assam recorded heatwaves.
Many other states in northwest, central and south India have also experienced heatwaves in this period. Many cities across the country such as Chandigarh have also broken their all-time temperature records in May. Chandigarh recorded a maximum temperature of 46.7°C on May 29, breaking its previous record of 46.5°C set on May 28, 1988.
In the month of May, northwest and central regions of India are generally prone to heatwaves. But the current heatwaves seem exceptionally punishing as has been witnessed in Delhi.
The immediate meteorological reason for the heat are the hot winds blowing from the Arabian Peninsula in West Asia towards Rajasthan and the rest of northwest India.
The other cause are warm winds blowing in from over the Arabian Sea, a consequence of the record-breaking warmth that the sea has absorbed in the past couple of years, building on the increasing ocean heat content in the past few decades.
“The winds are sweeping in from the warm Arabian Sea and hot West Asia. So Delhi is getting cooked,” Raghu Murtugudde, professor of climate studies at the Indian Institute of Technology, Bombay and emeritus professor at the University of Maryland, told Down To Earth.
The Arabian Sea has warmed by around 1.2°C to 1.4°C in the past few decades, according to a research paper published in the journal Earth Science Reviews in March 2022. The World Meteorological Organization (WMO) stated recently that the sea surface temperatures (SSTs) in all global ocean basins have been on a record-breaking streak for the past 13 months.
Copernicus Climate Change Service of the European Union also pointed out that “the record-high SSTs were associated with marine heatwaves around the globe, including in much of the North Atlantic Ocean, parts of the Mediterranean Sea, Gulf of Mexico and the Caribbean Sea, Indian Ocean and North Pacific Ocean.”
The El Nino climatic phenomenon is another factor that is often cited as a reason for record-breaking temperatures on land and in the oceans. But the current El Nino event that began in July 2023, is in its waning phase with a good possibility of a La Nina event, which generally cools down global temperatures, to begin any time between July and September.
But how rare is this occurrence of record-breaking heatwaves over northwest India and what would be its frequency in a rapidly warming world?
“Will it happen again soon? Hard to say if such a combination will happen anytime soon in terms of warm 2023 and the continued warm 2024. Volcano, El Nino , cleaner air and global warming combined to spike the hot temperatures beyond expectations,” explained Murtugudde.
“We may return to the rates of warming before 2023 especially if a strong La Nina kicks in and stays for a few years. Unfortunately, we are not good at predicting these. Hence, saying this is the new normal is a bit dangerous,” he cautioned.
The heatwaves though may continue in the month of June for northwest and central India, while the southern states remain cooler because of the rains from the southwest monsoon.
The much-awaited monsoon made an onset over Kerala and most of the Northeastern states on May 30, two days earlier than normal and one day earlier than predicted by the IMD.
But the monsoon winds will probably take around a month to reach Delhi and northwest India. The normal date of monsoon onset over Delhi is June 30, if the winds do not stall — a condition that has been observed in the past few years.
IMD also expects above normal heatwave days for much of northwest and central India in June 2024, while it also predicts below normal rainfall in the same period, according to the second long range monsoon forecast issued by the weather agency on May 27.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
