How will the haj change as global temperatures rise?
Keeping pilgrims safe will become harder and costlier as the world gets hotter
Al-Maqdisi, a medieval Islamic geographer, described the Hejaz region in Saudi Arabia as an area of “suffocating heat, deadly winds and clouds of flies”. It is an inhospitable spot. But it is also the site of the haj, the annual pilgrimage that is one of the five pillars of Islam and that every Muslim who is able must complete once in their lifetime.
Before the pandemic led to a temporary cap on numbers, 2.5m pilgrims attended each year. By 2030 the Saudi government wants 6m. Today the pilgrimage is made possible by mitigating the heat with technology and infrastructure. But as the world warms, keeping hajis safe will be harder and costlier.
Even in winter, average temperatures near Mecca rarely fall below 20°C. In large crowds the press of bodies makes it harder for each individual to dispel heat. But July to October, when the air is hottest and still damp, is most dangerous. The combination of heat and humidity gives the “wet-bulb” temperature. The higher it is, the less organisms can avoid overheating by sweating since moisture evaporates more slowly.
Maximum wet-bulb temperatures around Mecca, °C
Projected daily average by month
18
24
26
28
29.5
20
22
2020
2030
2040
2050
2060
2070
2080
2090
Jan
Months of the haj
Jun
Danger
Extreme danger
Dec
*CMIP5 multi-model mean based on current emissions trajectory (RCP4.5)
Sources: WMO Regional Climate Centre at KNMI; The Economist
At wet-bulb temperatures of more than about 29°C, almost any activity outside becomes treacherous. At 35°C scientists think it becomes impossible for humans to cool down, meaning they effectively cook (testing this on actual people is, for obvious reasons, tricky). At these levels, even a young, healthy person with unlimited water and shade is expected to die in about six hours. The fatal threshold for the elderly or those with medical conditions is much lower. The average haji spends about 20 to 30 hours outdoors.
Roughly one in every 1,000 religious visitors to Mecca dies, many from cardiorespiratory attacks. The highest wet-bulb temperature recorded during the haj was 27°C in September 2015. That year hundreds, probably thousands of pilgrims perished in a crush: doctors reported many deaths from heat stroke.
But the Arabian Peninsula is heating up significantly faster than the average for the rest of the globe. Even if all countries meet their current commitments to cut greenhouse-gas emissions—a big if—climate models project that wet-bulb temperatures could exceed 29°C on 15% of haj days between 2045 and 2053, and 19% between 2079 and 2086. It may get much worse.
Serious efforts have already been made to protect pilgrims from the heat. Tents to sleep in are air-conditioned. Significant tracts of the pilgrimage are conducted inside vast climate-controlled tunnels. Walkways and prayer sites are lined with fans pumping out water vapour. At least 4,000 hospital beds and 25,000 medics are made available and further hospital areas are being built within the Grand Mosque complex in Mecca. Wealthier pilgrims can travel by air-conditioned trains—which run for just seven days a year. Those with less money take crowded buses (or walk).
The logistics of the modern haj are mind-boggling. During the five official days of the haj, millions of pilgrims carry out multiple rituals in five locations, spread over around 170 square kilometres.
The Grand Mosque
Google, © 2022 Maxar Technologies
Before the haj begins, pilgrims go to the Grand Mosque in Mecca to perform the tawaf: circling seven times around the Kaaba, a cube-shaped black shrine.
Many then perform the sa’i, walking or running between two hills seven times (repeated later). Covering a total of 5km, the sa’i now occurs entirely within vast air-conditioned tunnels.
On the first day of the haj proper, pilgrims travel to the Mina encampment, 8km away. Most take buses, some the train. Others walk through climate-controlled tunnels. Mina’s 100,000 communal tents are now air-conditioned, but pilgrims on more expensive packages get roomier—and cooler—accommodation.
At dawn of the second day, pilgrims depart for Mount Arafat, walking about 2km outside to catch buses or trains. Some hike the whole 12km, believing that to be a holier endeavour, along the largest pedestrian road in the world. Though uncovered, the road has asphalt which is specially coated to stop it absorbing heat.
The day is then spent in prayer on the Arafat plains, mostly under shade or in tents (the priciest have the best cooling systems). Many pilgrims scale the peak of the mountain.
At sunset pilgrims go to Muzdalifah, a rocky patch of desert near Mina. Unlike the journey to Arafat, almost everyone walks this 9km stretch, to emulate the Prophet Muhammad. Buses, though, are available for the old or infirm.
The night at Muzdalifah is spent outside: no tents allowed. High night-time temperatures can be particularly dangerous, as the body doesn’t get its usual respite from heat.
On the morning of the third day, pilgrims gather stones from the ground around Muzdalifah before they walk to the Jamarat complex near Mina, around 4km away.
At Jamarat, pilgrims throw pebbles at pillars representing the devil, either from the ground or from a footbridge overlooking them. At its peak, some 300,000 pilgrims pass over the main bridge per hour. The pillars and the area around them are enclosed under a huge, air-conditioned canopy, but the press of people can still send temperatures soaring.
From there pilgrims return to Mecca and the Kaaba, for another tawaf and sa’i. They sleep back in Mina.
On the fourth and fifth days, pilgrims return to Jamarat to stone the devil again. Pilgrims’ hair is cut and animal sacrifices are carried out on their behalf in remote slaughterhouses.
On the sixth and final day, pilgrims leave the Mina camp for Mecca once more, and perform a final tawaf. The haj is over. Many people travel on to Medina, Islam’s second-holiest city. The main mosque there is now shaded by an enormous lattice of mechanical canopies.
Many poorer Muslims must save for years and go on the haj when they are older and more vulnerable. In future, demand may rise in cooler years, pushing prices up and forcing the poor to go in the cheapest but most dangerous months (based on a lunar calendar, the haj’s dates of the pilgrimage shift forward by about 11 days each year). One solution in very hot years could be an age limit, as was imposed during the pandemic.
The haj has persisted for many centuries; it will not disappear. One haji, in 1807, rhapsodised about pilgrims’ forbearance, “through a thousand dangers” and “fatigues of every description”. But as temperatures increase, so too, for some, will the difficulties of devotion. ■
Sources: A.Abbas/Magnum, AP, Alamy, Getty Images