top of page
  • brewtoch

The Hajj is Getting Hotter (and so is everything else)!

Updated: Aug 7, 2022

This week's blog is about climate change and how it will affect the Hajj in the coming years. I have run across four academic/institutional studies that suggest specific outcomes that will affect the pilgrims that attend the Hajj. The Saudis have done an excellent job of being caretakers and hosts of the pilgrimage to Mecca, but their work is not done. The bad news is that the temperature is getting hotter, affecting the desert kingdom and all those countries in the Middle East. The good news is that they have approximately 30 years to improve facilities that will enhance and protect the Mecca-bound pilgrims. The Hajj is one of the largest religious pilgrimages reaching upwards of three million pilgrims annually. The Hajj also affects geopolitical relations between numerous countries that allow their citizens to go on the pilgrimage. Incidents that cause harm and death to other countries' citizens can cause sour political ties. It is in the Saudi's best interest to address the problems now if they know what they are.

Study #1:

A 1989 study entitled "Temperature and aggression: Ubiquitous effects of heat on occurrence of human violence" by C.A. Anderson was published in the journal Psychological Bulletin, 106 (1), 74-96. As the title indicates, the study shows a correlation between heat and aggression. Aggression is measured as violent crime, spousal abuse, and horn-honking. Saudi Arabia already knows the impact that hot temperatures can have. The deadliest stampedes during Hajj both occurred during days with extreme heat and humidity. On July 2, 1990, the temperature reached 41.7° C (107° F), and 1,426 pilgrims died in a stampede. Twenty-five years later, on September 24, 2015, temperatures reached 48.3° C (119° F), and more than 2,000 pilgrims again died in a stampede. Outside the Middle East, there are documented cases where riots occurred during heat waves in both America and India.

Study #2

In 2017, another study about heat waves in India came out. "Increasing probability of mortality during Indian heat waves" was written by 12 scientists from the University of California, Irvine. Their paper appeared in the journal Science Advances vol 3(6). They proclaim that temperatures in the Middle East will increase by 2.2 to 5.5 degrees Celsius (4 to 10 degrees F) by the end of the 21st century. The average temperature in Mecca during the past 30 years has increased by 2° C (3.8° F). Their main finding was that slight increases in outside temperatures caused exponential increases in heat stress among the young, elderly, and poor.

Study #3

It's not the heat; it's the humidity. Most people know that humid heat is more brutal to handle than dry heat. Mecca is located 45 miles inland from the Saudi city of Jeddah, which lies on the Red Sea. When winds blow out of the west, humid air from the Red Sea penetrates inland, raising the heat stress to dangerous levels. This study, entitled "Potentially Fatal Combinations of Humidity and Heat Are Emerging Across the Globe," published in 2020 by Raymond et al. in Science Advances, identified numerous situations in which humidity combines with heat to kill humans. Research shows that temperatures above 29.1° C (84.4°F) with 45% relative humidity can be fatal if experienced for 6 hours or more. What happens is that the human body can no longer cool itself via sweat because it is so hot that sweat doesn't evaporate properly. Pilgrims under these extreme conditions would be at serious risk of heat stroke and even death. Imagine the temperature 10 to 20 degrees hotter with the same humidity. It would be like cooking a person to death.

Study #4

This last study comes out of MIT, a prestigious U.S. university. A 2019 paper by MIT scientist Suchul Kang and colleagues, "Future Heat Stress During Muslim Pilgrimage (Hajj) Projected to Exceed Extreme Danger Levels," painted a very concerning picture for future Hajj pilgrimages in a warming climate.

The floor of the Great Mosque, its covered areas, and the tent city in Mina are air-conditioned. So are the buses that take pilgrims to different locations. However, there are parts of the Hajj where pilgrims spend about 20 to 30 hours outdoors over five days. The main outdoor activities are:

  • Praying outside the Great Mosque Al Haram for a few hours on two different occasions.

  • Standing on Mount Arafat where the Prophet gave his farewell sermon. This activity lasts one day between sunrise and sunset and is the most important part of the Hajj.

  • Stoning of the Devil near Mina, an activity that requires a lot of walking, is repeated over three days.

The satellite photo of Mecca comes from the MIT study.

These activities, as well as the indoor rituals, take place over five days identified on the Muslim calendar. The Muslim calendar follows the lunar cycle and is shorter than the solar calendar by an average of 11 days per year. The Hajj moves up 11 days on the calendar year after year. For example, in 2021, the Hajj was July 17-22. In 2022, the Hajj was July 7-12. Next year in 2023, the Hajj will start sometime during the last week in June. Given the predictability of when the Hajj will begin in future years, it's easy to calculate when the Hajj will be in the summer months again.

The study by MIT ran a simulation estimating when the deadly combination of humidity and temperature would hit the Arabian desert. They estimated that between 2045 and 2053, the summer temperatures with high humidity would exceed dangerous levels 20% of the time. Fast forward to 2079 to 2086, and harmful conditions will expand to 42% of the summer.

What to do?

There are several ways to go about this. One possibility is to change the rules by restricting the elderly and the young. In 2022, an age cap of 65 was implemented, penalizing wealthy and Western pilgrims who have worked all their lives to earn money for this trip. Another possibility is to change the Hajj dates or make year-round pilgrimages acceptable except for the summer months. Another option is building facilities that will encapsulate the sacred places and protect them from the outside furnace. The technology is there, but another question is whether the capital exists.

Islam is the world's fastest-growing major religion and is projected to continue. The number of pilgrims will grow, and the requirement for the Hajj is not going away. It will be interesting to see how Saudi Arabia handles the challenge.

Thanks to Tommaso.sansone91 for his 2019 climate change icon via Wikipedia Commons.

16 views0 comments

Recent Posts

See All


bottom of page