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. Saudi Arabia, which hosts hajj, is the world’s second biggest oil producer and a long-term obstructer of climate action. Muslims around the world are now celebrating the start of Eid al-Adha as devotees in Mecca finish their rituals during this year’s pilgrimage. Hajj follows the Islamic lunar calendar, which means it falls earlier each successive year.…