The March-April period was the hottest on record for that time of year in Pakistan and India.
Paris:
The debilitating heat wave that ravaged India and Pakistan in March and April was made 30 times more likely by climate change, experts quantifying the impact of global warming on extreme weather events said in a quick-response report Monday.
Before the onset of human-induced climate change, the odds of such an event occurring would have been about once every 3,000 years, senior author Friederike Otto, a scientist at the Grantham Institute at Imperial College London, told AFP.
Global warming of 1.2 degrees Celsius to date has shortened the so-called return period for extreme heat of comparable duration and intensity in South Asia to once a century, they and colleagues at the World Weather Attribution (WWA) found – consortium.
But as the planet continues to warm, the interval between such killer heat waves will shrink even further.
If Earth’s average surface temperature rises another four-fifths of a degree to 2C above pre-industrial levels, “a heat wave like this would be expected as much as once every five years,” they concluded.
A world of 2°C is a disturbingly plausible scenario: Current national commitments to curb carbon pollution under the Paris Agreement would lead to global warming of 2.8°C.
“Whether today’s most impactful heatwaves could have occurred in a pre-industrial climate is quickly becoming an outdated question,” Otto said.
“The next frontier for attribution science is to inform decision-making about adaptation in the face of unprecedented future heat,” she said by email.
“This means the most important aspect of our research is what it says about a 2C world.”
The March-April period was the hottest on record for that time of year in Pakistan and India.
It will be months before the full toll in lost lives and economic damage can be calculated, including hospitalizations, lost wages, missed school days and reduced working hours.
More than 90 deaths have been directly attributed to the heat wave, but previous hot spells in the past decade suggest the number will rise much higher, perhaps in the thousands.
One of the consequences was immediate.
The devastating heat combined with 60 to 70 percent less rain than usual turned what promised to be a great wheat crop in India into an agricultural disaster.
– ‘Existential threat’ –
As a result, India last week blocked millions of tons destined for sale abroad, pushing up world prices already hard hit by Ukraine’s war-torn crippled wheat exports.
The unprecedented duration of the heat wave, which saw power outages as temperatures soared into the 40s, suggests climate-sensitive countries are racing against time to prepare for a climate-ravaged future, the report said.
Already, “the limits of adaptation for a large, poor population of the region are being exceeded,” Islamabad-based climate scientist and co-author Fahad Saeed warned.
“You can imagine how bad it would be even for a world with a temperature of 1.5 degrees Celsius,” he said, referring to the ambitious goal of the Paris Agreement to cap the rise in global temperature.
Any warming above 1.5°C, he added, would pose an “existential threat” to vulnerable populations without access to air conditioning or other ways to stay cool.
The new report — which averaged daily maximum temperatures in March and April over much of northwestern India and southern Pakistan — may underestimate the frequency of such heat waves, today and in the future, the authors said.
Indeed, a review by the UK’s Met Office using slightly different methods concludes that warming has so far increased the probability of the India/Pakistan scorcher 100-fold.
Scientists have long predicted such effects, but only recently have more data, better models and increased computing power made it possible to calculate how much a given weather disaster is exacerbated by global warming.
For example, the WWA determined that the heat wave that gripped western North America last June — pushing temperatures in Canada to a record 49.6°C (121F) — would have been “virtually impossible.” without human-induced climate change.
“As long as greenhouse gas emissions continue, such events will become an increasingly common disaster,” Otto said.
Heat waves, she noted, are the deadliest of all extreme weather events today.
(Except for the headline, this story has not been edited by DailyExpertNews staff and has been published from a syndicated feed.)
