KARACHI, Pakistan (AP) – The devastating heat wave that struck southern Pakistan last weekend is slowly subsiding but the toll was still climbing Thursday, to a total of 860 confirmed deaths, a senior health official said.

Pakistan’s deadliest heat wave on record comes just weeks after soaring temperatures caused nearly 2,200 deaths in neighboring India, raising fears that South Asia could be seeing some of the devastating effects of human-caused climate change.

The crisis centered in the southern port city of Karachi was worsened by poor local services, including a faulty power grid and shortages of potable water. And the heat wave struck as the city’s Muslim majority was observing the dawn-to-dusk fasting month of Ramadan.

Jam Mehtab Hussain, the provincial health minister in the southern Sindh province, of which Karachi is the capital, said that despite lower temperatures people were still being admitted to hospitals with heat-related ailments – though in smaller numbers than in previous days.

Ahmad Kamal, a spokesman for the National Disaster Management Authority, said authorities were providing free medical treatment to people in Karachi. He said the situation was improving due to lower temperatures.

On Thursday, the temperature dropped to 34 degrees Celsius (93.2 degrees Fahrenheit) in Karachi from a high of 45 degrees Celsius (113 degrees Fahrenheit) on Sunday.

TV footage showed ambulances transporting heatstroke patients to hospitals, where people held small rallies against power outages, which had exacerbated the effects of the heat wave.

Observant Muslims, who make up the majority of Karachi’s 20 million residents, were meanwhile abstaining from food and water during long summer days. A single sip of water invalidates the fast, but Muslims are discouraged from fasting if they are sick or if doing so would cause physical harm.

Allama Tahir Ashrafi, a Pakistani cleric, called on sick and elderly people to avoid fasting until the weather improves.

“Those people who cannot fast because of health reasons should not fast these days. There is no need to risk your lives,” he said. Volunteers were meanwhile distributing clean drinking water and juice throughout the day.

TV footage showed women crying over the bodies of loved ones who had died because of the heat.

Syed Mannan Ahmed said his father collapsed Tuesday while going to buy groceries from a nearby shop. He said his family rushed the 64-year-old to a hospital but could not get treatment in time because it was packed with victims. Then they found that most of the mortuaries were full as well.

Another Karachi resident, Mohammad Ayaz, said hundreds of people were sleeping outside because of long power cuts. Wakil Ahmed said the weather had improved from previous days, when it was so hot it became difficult to breathe. He said Thursday brought clouds and a slight breeze.

While climate scientists can’t blame human-caused global warming for Pakistan’s heat wave without a time-consuming study, several said it fits with what is expected from climate change.

“The deadly heatwave that has killed several hundred people in Karachi, Pakistan is clearly a harbinger of things to come with the changing climate,” said Saleemul Huq, director of the International Center for Climate Change and Development in Bangladesh and a prominent climate scientist.

“Even if this particular event cannot be unequivocally attributed to human induced climate change, we can certainly expect such heat waves with greater frequency in future.”

Numerous studies over the past three years show that the number of prolonged heat waves has soared, and scientists have calculated that about three quarters of record heat is due to human-caused climate change.

“I would estimate that the likelihood for such a heat wave in Pakistan would have increased several-fold due to global warming,” said climate scientist Stefan Rahmstorf at the Potsdam Institute for Climate Research in Germany. “More likely than not, it would not have happened without global warming.”


AP Science Writer Seth Borenstein in Washington, and Associated Press writers Muhammad Farooq in Karachi, Pakistan, and Munir Ahmed in Islamabad contributed to this report.

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