Northwest and central India recorded the highest average maximum temperatures in April since 1900 as there would be no respite for the region in May, the weather office said on Saturday.
Releasing the monthly outlook for temperature and rainfall for May, India Meteorological Department Director General Mrutyunjay Mohapatra said most parts of the country, barring parts of southern peninsular India, were likely to experience warmer nights in May.
With scanty rains owing to feeble western disturbances, northwest and central India experienced the hottest April in 122 years with average maximum temperature touching 35.9 degrees Celsius and 37.78 degrees Celsius, respectively.
The northwest region had previously recorded an average maximum temperature of 35.4 degrees Celsius in April 2010, while the previous record for the central region was 37.75 degrees Celsius in 1973.
“Most parts of northwest India – J&K, Himachal, Punjab, Haryana, Rajasthan, Gujarat – are expected to experience above normal temperatures in May,” Mohapatra said.
“The average rainfall in May 2022 over the country is most likely to be above normal,” Mohapatra said.
However, parts of northwest and northeast India as well as the extreme southeast Peninsula are expected to get below normal rainfall in May, Mohapatra said.
Mohapatra did not rule out parts of western Rajasthan reporting temperatures more than 50 degrees Celsius.
“I cannot make that forecast, but it is climatologically possible as May is the hottest month,” Mohapatra said to questions on whether temperatures would top 50 degrees Celsius this summer season.
Banda in Uttar Pradesh had recorded a high of 47.4 degrees Celsius on previous Saturday, the highest in the country.
According to Mohapatra, average temperatures observed pan-India for April was 35.05 degrees, which was the fourth highest since 1900, when the weather office started keeping weather data.
The high temperatures in March and April were attributed to “continuously scanty rainfall activity”, he said.
In March, northwest India recorded a deficit in rainfall of around 89 per cent, while the deficit was nearly 83 per cent in April, mainly on account of feeble and dry western disturbances, Mohapatra said.
North India witnessed six western disturbances, but they were mostly feeble and moved across the higher parts of the Himalayas, he said adding that the last three western disturbances caused strong winds in parts of Delhi and dust storms over Rajasthan in April.
WORST YET TO COME FOR INDIA, PAKISTAN:
The devastating heatwave that gripped India and Pakistan over the last two months is unprecedented, but worse — perhaps far worse — is on the horizon as climate change continues apace, top climate scientists said.
Even without additional global warming South Asia is, statistically speaking, ripe for a “big one” in the same way that California is said to be overdue for a major earthquake, according to research published this week.
Extreme heat across much of India and neighbouring Pakistan in March and April exposed more than a billion people to scorching temperatures well above 40 Celsius (104 Fahrenheit). The hottest part of the year is yet to come.
“This heatwave is likely to kill thousands,” tweeted Robert Rohde, lead scientist at Berkeley Earth, a climate science research non-profit.
The number of excess deaths, especially among the elderly poor, will only become apparent in hindsight.
Heatwave mortality in India has increased by more than 60 percent since 1980, according to the country’s Ministry of Earth Sciences.
But “cascading impacts” on agricultural output, water, energy supplies and other sectors are already apparent, World Meteorological Organisation chief Petteri Taalas said this week.
Air quality has deteriorated, and large swathes of land are at risk of extreme fire danger.
Power blackouts last week as electricity demand hit record levels served as a warning of what might happen if temperatures were to climb even higher.
For climate scientists, none of this came as a surprise.
“What I find unexpected is most people being shocked, given how long we have been warned about such disasters coming,” said Camilo Mora, a professor at the University of Hawaii.
“This region of the world, and most other tropical areas, are among the most vulnerable to heatwaves.”
The new normal
In a benchmark 2017 study, Mora calculated that nearly half the global population will be exposed to “deadly heat” 20 days or more each year by 2100, even if global warming is capped under two degrees Celsius, the cornerstone target of the Paris Agreement.
To what extent is climate change to blame for the scorched Earth temperatures just now easing up in India and Pakistan? Scientists at Imperial College London’s Grantham Institute led by Friederike Otto, a pioneer in the field of attribution science, are crunching the numbers.
“How much more likely and intense this particular heatwave has become is something we’re still working on,” she told AFP.
“But there is no doubt that climate change is a huge game changer when it comes to extreme heat,” she added. “What we see right now will be normal, if not cool, in a 2C to 3C world.” Earth’s surface, on average, is 1.1C above preindustrial levels. National carbon cutting pledges under the Paris Agreement, if fulfilled, would still see the world warm 2.8 degrees.
In India and Pakistan, “more intense heat waves of longer durations and occurring at a higher frequency are projected,” the Intergovernmental Panel on Climate Change (IPCC) said in a recent landmark report.
“Before human activities increased global temperatures, we would have seen the heat that hit India around once in 50 years,” said Marian Zachariah, a researcher at Imperial College London.
“But now we can expect such high temperatures about once ever four years.” Continued global warming, in other words, guarantees greater heat extremes in the coming decades.
Sunburn inside the body
But things may get worse even sooner, according to a new study in Science Advances.
A team led by Vikki Thompson of Bristol University ranked the world’s most severe heatwaves since 1960. Their benchmark, however, was not maximum temperatures, but how hot it got compared to what would be expected for the region.
Surprisingly, South Asia was nowhere near the top of the list.
“When defined in terms of deviation from the local norm, heatwaves in India and Pakistan to date have not been all that extreme,” Thompson explained in a commentary.
By that measure, the worst scorcher on record over the last six decades was in Southeast Asia in 1998.
“An equivalent outlier heatwave in India today would mean temperatures over 50C across large swathes of the country,” Thompson said.
“Statistically, a record-breaking heatwave is likely to occur in India at some point.” What makes extreme heat deadly is high temperatures combined with humidity, a steam-bath mix with its own yardstick: wet-bulb temperature (WB).
When the body overheats, the heart ups the tempo and sends blood to the skin where sweating cools it down. But above a threshold of heat-plus-humidity this natural cooling system shuts down.
“Think of it as a sunburn but inside your body,” said Mora.
A wet-bulb temperature of 35C WB will kill a healthy young adult within six hours. Last week, the central Indian city of Nagpur briefly registered 32.2 WB.
“The rise in heatwaves, floods, cyclones and droughts that we have seen in this region so far are in response to just one degree Celsius,” Roxy Mathew Koll, a climate scientist at Indian Institute of Tropical Meteorology, told AFP.
“It is difficult for me to even imagine the impacts when the increase in global temperatures are doubled.”