International scientists report that the disastrous severe heat wave in India and Pakistan recently was made more likely by climate change.

They also say that such weather is likely to become more common.

World Weather Attribution is a group of weather scientists from Britain, France, India, the Netherlands, Switzerland, the United States, and the Red Cross. It released its report May 23.

The report says heat waves that affect a large area of Earth are rare --- happening once every 100 years. But it said climate change now makes big heat waves 30 times more likely.

The scientists said if the atmosphere's average temperature increases to 2 degrees Celsius more than pre-industrial levels, big heat waves could happen twice every hundred years or more, says Arpita Mondal, a climate researcher at the Indian Institute of Technology in Mumbai. She suggests heat waves as often as every five years are possible.

"This is a sign of things to come," the scientist said.

Conservative results

The results are conservative in comparison to others. Last week, Britain's Meteorological Office said the heat wave was probably made 100 times more likely by climate change.

Friederike Otto of the Imperial College of London also worked on the World Weather Attribution report.

"The real result is probably somewhere between ours and the (U.K.) Met Office result for how much climate change increased this event," the climate scientist said.

The heat wave has been very damaging. Indian cities and Pakistan reported temperatures above 45 degrees Celsius in the past weeks. Pakistan reported temperatures over 50 degrees Celsius in some places like Jacobabad and Dadu. Parts of India's capital New Delhi reported temperatures of 49 degrees this month.

India recorded the hottest March in the country since 1901, when such record-keeping began. April was the warmest on record in Pakistan and parts of India.

The effects have been widespread. A glacier burst in Pakistan, causing floods. The heat also damaged wheat crops in India. The problem forced the government to stop exports to nations facing food shortages linked to Russia's war in Ukraine. The heat wave also resulted in earlier than usual demand for electricity. The coal supply shrank leading to power shortages affecting millions of people.

‘What can we do?'

The effects on human health were also damaging. At least 90 people have died in the two countries. Scientists suggest the number is higher because deaths are not always officially recorded.

The Associated Press (AP) studied information from Columbia University's climate school. It found that South Asia is the most affected by heat stress. India is home to more than one third of the world's population that lives where temperatures are increasing.

Children and old people are most at risk from heat stress. Heat is also harder on the poor who do not have cooling systems, like air conditioners. Many poor people live in crowded, dirty neighborhoods in large cities.

Rahman Ali is a 42-year-old ragpicker in New Delhi. Ragpickers remove trash from people's homes and search through it for anything of value to sell. The job is very hard on his body and earns Ali less than three dollars a day.

"What can we do? If I don't work...we won't eat," said the father of two.

Some Indian cities have tried to find answers. The western city of Ahmedabad was the first in South Asia to design a heat wave plan for its population of over 8.4 million in 2013. The plan includes an early warning system that tells health workers and residents to prepare for heat waves. It permits administrations to keep parks open so that people can keep out of the sun. And it provides information to schools so they change class hours.

Dr. Dileep Mavalankar heads the Indian Institute of Public Health in the western Indian city of Gandhinagar. He helped design the 2013 plan. He said the city has also been experimenting with materials that may help cool the tops of houses. The aim is to build roofs that do not hold the sun's heat. Some people use white paint or low-cost materials like dried grass to protect their homes from the heat.

Most Indian cities are less prepared. India's federal government is now working with 130 cities in 23 states to develop similar plans.

Earlier this month, the federal government also asked states to train health workers in treating heat-related illnesses. It also asked that ice, chemical treatments, and cooling devices be available in hospitals.

Public health expert Mavalankar was not part of the group study. But he pointed to a lack of official warnings about extreme heat in most Indian cities. He said the local governments have just not, in his words, "woken up to the heat."

I'm Mario Ritter Jr. And I'm Faith Pirlo.

Aniruddha Ghosal reported this story for the Associated Press. Mario Ritter Jr. adapted it for VOA Learning English.