This article was originally published by The Guardian and is reproduced here as part of the Climate Desk collaboration.

A pilgrim at the Great Mosque of Mecca in Mecca, Saudi Arabia. Ali Mansuri via Wikipedia

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

Carbon dioxide emissions from fossil fuels mean scorching temperatures of 104 degrees F (40 degrees C) are now regularly experienced in May, the study showed. In past decades, such peaks would only have occurred in summer.…