Global heating is making hajj ever more dangerous, report finds

The hajj involves walking long distances outside over five days, often in scorching temperatures. Photograph: Anadolu/Getty Images

Global heating has “fundamentally altered” the climate of Mecca and is exposing millions of hajj pilgrims to extreme and dangerous heat even in months outside summer, new analysis has found.

Carbon dioxide emissions from fossil fuels means scorching temperatures of 40C (104F) are now regularly experienced in May, the study showed. In past decades, such peaks would only have occurred in summer. The researchers said that hajj, the annual Islamic pilgrimage to Mecca, would take place amid dangerous heat almost all year round by the end of the century without a rapid transition away from fossil fuels.