Study shows climate change making hajj hotter, less safe

The annual hajj pilgrimage in western Saudi Arabia, one of the largest religious gatherings globally, is becoming increasingly dangerous due to rising temperatures linked to climate change. According to a study by the Britain-based World Weather Attribution, May temperatures in Mecca now mirror summer conditions from the 1980s, shrinking the safe window for pilgrims. The hajj’s timing, dictated by the Islamic lunar calendar, shifts back by about 11 days each year in the Gregorian calendar, meaning this year’s event took place at the end of May, while the 2027 hajj is expected in mid-May. Researchers warn that while the pilgrimage will gradually move closer to winter, this will not offset the overall temperature rise. Climate change has extended extreme heat into historically cooler months, with average temperatures above 32°C—once typical of summer between 1970 and 1990—now occurring almost yearly in May. The study attributes a 3.5°C increase in these averages since pre-industrial times to climate change. The hajj’s mainly open-air rituals, a cornerstone of Islam, expose hundreds of thousands of pilgrims to severe heat risks. After over 1,300 deaths during the 2024 pilgrimage in temperatures exceeding 50°C, Saudi authorities introduced stronger anti-heat measures, primarily through widespread air conditioning. A 2019 study in *Geophysical Research Letters* projected that heat stress during the hajj could again surpass the 'extreme danger threshold' between 2047–2052 and later between 2079–2086, underscoring the growing challenge of climate change for future pilgrimages.