Record-shattering temperatures this summer have scorched countries from Morocco to Saudi Arabia and beyond, as climate experts warn that the severe weather could be a harbinger of worse to come.

In coming decades, U.N. officials and climate scientists predict that the mushrooming populations of the Middle East and North Africa will face extreme water scarcity, temperatures almost too hot for human survival and other consequences of global warming.

If that happens, conflicts and refugee crises far greater than those now underway are probable, said Adel Abdellatif, a senior adviser at the U.N. Development Program’s Regional Bureau for Arab States who has worked on studies about the effect of climate change on the region.

“This incredible weather shows that climate change is already taking a toll now and that it is — by far — one of the biggest challenges ever faced by this region,” he said.

These countries have grappled with remarkably warm summers in recent years, but this year has been particularly brutal.

Parts of the United Arab Emirates and Iran experienced a heat index — a measurement that factors in humidity as well as temperature — that soared to 140 degrees in July, and Jiddah, Saudi Arabia, recorded an all-time high temperature of nearly 126 degrees. Southern Morocco’s relatively cooler climate suddenly sizzled last month, with temperatures surging to highs between 109 and 116 degrees. In May, record-breaking temperatures in Israel led to a surge in ­heat-related illnesses.

Temperatures in Kuwait and Iraq startled observers. On July 22, the mercury climbed to 129 degrees in the southern Iraqi city of Basra. A day earlier, it reached 129.2 in Mitribah, Kuwait. If confirmed by the World Meteorological Organization, the two temperatures would be the hottest ever recorded in the Eastern Hemisphere.

The bad news isn’t over, either. Iraq’s heat wave is expected to continue this week.

Stepping outside is like “walking into a fire,” said Zainab Guman, a 26-year-old university student who lives in Basra. “It’s like everything on your body — your skin, your eyes, your nose — starts to burn,” she said.

Guman has rarely left home during daylight hours since June, when temperatures started rising above 120 degrees and metal objects outside turned into searing-hot hazards.

About that time, Aymen Karim also began feeling trapped.

The 28-year-old engineer at a government-run oil company in Basra said employees were ordered to stay home for several days in the past month. He and his family try not to go outside before 7 p.m.

“We’re prisoners,” Karim said.

Bassem Antoine, an Iraqi economist, said the weather has inflicted serious damage to the country’s economy. He estimates that Iraq’s gross domestic product — about $230 billion annually — has probably contracted 10 to 20 percent during the summer heat.

Iraqi officials say scores of farmers across the country have been struggling with wilting crops, and general workforce productivity has decreased.

Hospitals, meanwhile, have seen an uptick in the number of people suffering from dehydration and heat exhaustion.

Tens of thousands of Iraqis displaced by battles between government forces and Islamic State militants have endured the heat in tents and other makeshift shelters. Humanitarian organizations have been unable to reach all of them because of budget constraints, restrictions by Iraq’s government and risks associated with operating in war zones.

“A lot of these people are probably dying, but it’s hard to know,” said an official at an aid organization who was not authorized to discuss the issue publicly and so spoke on the condition of anonymity.

In Baghdad, the capital, the temperature measured at the international airport has reached 109 degrees or higher nearly every day since June 19. The city has been 10 and even 20 degrees warmer than normal for this time of year.

The government has declared multiple mandatory official holidays because of the heat. When that happens, many public employees turn up to work anyway because of the air conditioning available at government offices.

Most Iraqi homes and businesses suffer daily power cuts for 12 hours or more, and most Iraqis — unlike their rich neighbors in Kuwait and Saudi Arabia — are too poor to afford 24-hour air conditioning anyway. Such a luxury requires paying expensive fees for gas-powered generators.

During daylight hours, Baghdad’s streets are empty, but some businesses remain open. It’s either sweat at work or starve at home, said Eissa Mohsen, who owns a fruit stand in the Karrada area of downtown Baghdad.

“Look over there! That’s an air-conditioning unit, but I can’t afford to pay the generator fees to run it,” he said at his shop on a recent day.

The immediate cause of all this misery is a stubborn ­high-pressure system, but a fundamental shift in the country’s weather patterns appears to be taking place, said Mahmoud ­Abdul-Latif, spokesman for Iraq’s meteorological department. In Baghdad, he said, the number of days with temperatures at 118 degrees or higher has more than doubled in recent years.

“If you look back 40 years ago, you’d have these temperatures for four or five days, but then the wind would kick up dust and that would cool the surface. That’s just not happening now,” he said.

Climate scientists say this shouldn’t be surprising.

A study published by the journal Nature Climate Change in October predicted that heat waves in parts of the Persian Gulf could threaten human survival toward the end of the century. Researchers at the Max Planck Institute for Chemistry and the Cyprus Institute in Nicosia recently predicted a similarly grim fate for the Middle East and North Africa, a vast area currently home to about a half-billion people.

The region’s governments are generally not prepared to deal with rapidly growing populations and climactic shifts, said Francesca de Châtel, an Amsterdam-based expert on Middle Eastern water issues. For years, she said, they have failed to address these problems adequately despite warnings from climate experts and U.N. agencies, and it may be too late now.

The United Nations predicts that the combined population of 22 Arab countries will grow from about 400 million to nearly 600 million by 2050. That would place tremendous stress on countries where climate scientists predict significantly lower rainfall and saltier groundwater from rising sea levels. Already, most countries in the region face acute water crises because of dry climates, surging consumption and wasteful agricultural practices.

Analysts point to inadequate government handling of an unprecedented drought in Syria as a trigger for the country’s devastating civil war, which has produced extraordinary refugee flows that have spilled into Europe.

Last year, Iraqis rallied in Baghdad against their government’s inability to provide enough electricity during another scorching summer heat wave. Little, if anything, resulted from those demonstrations. According to some estimates, Iraq’s population of about 33 million people will nearly double by 2050.

“The countries in the region are not prepared to cope with the effects of climate change,” said de Châtel.

Such a blistering future doesn’t seem like a far-off possibility to 33-year-old Arkan Farhan, who lives with his family near Baghdad in a tin hut at camp for people displaced by the Islamic State.

Last month, he said, he contracted typhoid from a communal water source that has become particularly crowded — and filthy — this summer. To cool off, his sons use it to fill a pan for bathing.

This month, his 69-year-old father, Jassam, was taken to the hospital after passing out from the heat.

“Fortunately, he was only bruised. He didn’t break any bones,” Farhan said of his father while sitting in his sweltering shack. “Iraqis are strong people. But this heat is like a fire. Can people live in fire?”