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 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.
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.
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.
Source: The economist
