How Extreme Heat Is Proving a Major Challenge for Hajj

Amid sweltering temperatures in Saudi Arabia, concerns are mounting about the welfare of pilgrims flocking to Mecca this week to perform the annual Hajj, one of the five pillars of Islam.

More than 8,400 people have been treated for heat stroke or exhaustion, according to data compiled by the Saudi Gazette. The mercury has regularly topped 44°C (111°F) this week, weather data from Saudi Arabia’s National Center for Meteorology shows.

Islam follows a lunar calendar, meaning that the timing of Hajj changes every year. But it will continue to fall in Saudi Arabia’s hottest months until 2026. What makes authorities fret this year, however, is the scale of pilgrims arriving.

The kingdom has billed this year’s Hajj—which runs from June 26 to July 1—as “the largest in history” and is set to welcome over 2 million Muslims. That dwarfs the 10,000 pilgrims who arrived in 2020, the 60,000 in 2021, and the 1 million in 2022, when COVID-19 restrictions were loosened that year.

A maximum age limit of 65, which was introduced during the COVID-19 pandemic, has also been scrapped this year—raising further concerns about vulnerable elderly people.

But experts say that Saudi authorities take the safety and well-being of Hajj pilgrims dearly. “The government of Saudi Arabia, for all their flaws, takes their duty as the hosts of Hajj very seriously. And so it may be that, partially for PR purposes, they don’t want significant mass casualty or injury events at Hajj,” says Yara Asi, assistant professor of global health at the University of Central Florida. “This is supposed to be a holy time, a gathering of global Muslims, a once in a lifetime opportunity. They want it to go well.”

As pilgrims descend on Mecca, here’s what to know about the risks of extreme heat underpinning the pilgrimage.

Why are temperatures so high?

“It’s well over 40°C [104°F] now, but, of course, that’s not automatically attributable to climate change because it’s a desert,” says Jos Lelieveld, a professor at the Max Planck Institute for the Advancement of Science. “But we know from measurements—meteorological measurements—and from our modeling studies that things are getting really hot in the Middle East, especially in the Gulf region.”

Even winter temperatures in Mecca rarely fall below 20°C (38°F), and when crowds are involved, the concentrations of human bodies makes it harder to dispel heat. From July to October, air is both hot and damp there, which gives way to “wet-bulb” conditions—a combination of dry air temperature and humidity that can make it harder for bodies to cool down.

Wet-bulb temperatures have risen on average nearly 2°C (3.6°F) over the past three decades, according to Yale Climate Connections, a multimedia nonprofit focused on climate change. Temperatures in the Middle East are warming twice as fast as the rest of the world, meaning that it is becoming increasingly hotter than when the Prophet Muhammad first inaugurated the Hajj in the 7th century.

“For many in the world, climate change is still a relatively abstract concept depending on where you live,” Asi says. “However, for the Middle East and especially, you know, the area around the Gulf, the Levant, it is already happening.”

What safety measures has Saudi Arabia put in place?

In previous years, stampedes and crowd control issues have been the most pressing public safety concern, with hundreds dying at a time in several incidents throughout the 1990s to the 2010s. Saudi authorities are now increasingly focusing on extreme heat as well.

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To tackle the issue, the kingdom has put in place some measures to minimize the chances of heat stroke and other ailments. Worshippers at the Grand Mosque are being sprayed with water via automatic cooling systems, and free bottles and umbrellas are being distributed. Additionally, over 32,000 health workers have been enlisted to treat anyone who feels unwell, while more hospital beds have been made available, according to Al Jazeera.

But Asi says this may not be enough. “Especially for elderly people, people with comorbidities—people with Type 2 diabetes, people with weak hearts with, you know, previous chronic conditions—they are the primary targets for this and they are the least likely to be able to quickly find and reach help, especially if they’re there without family,” she says.

Unless Saudi authorities step in to decide who is not healthy enough to participate in Hajj—a major administrative undertaking—there is not much they can do to protect all pilgrims. “I would expect that especially vulnerable people will have real problems with this heat and there [will] even be deaths,” Lelieveld says.

What does the future of Hajj look like?

As climate change accelerates, it could force more elderly away. “At some point, we may see a decrease in the vulnerable populations traveling to Hajj,” Asi says, noting that hospital admissions for heat exhaustion and heat stroke typically affect over 55s.

“Even though Hajj tends to be a lifetime goal you save up for, people may try to go when they are younger to prevent this kind of incident,” Asi adds. With awareness, she says, families may be more likely to leave behind vulnerable family members such as grandparents.

But as both Asi and Lelieveld note, these are only stopgap measures in a warming climate. Saudi Arabia remains a top-10 emitter given its oil-reliant economy.

“We see this a lot in the Gulf where their governments deal with climate initiatives and green buildings or whatever the latest trend is but what they won’t do is cut off their dependence and the world’s dependence on their fossil fuels,” Asi says. “So they’re going to put as many bandages on this injury until the wound is simply too large.”