Life-threatening heat waves sweeping the Middle East, southern Europe and the US have been made “five times more likely” thanks to climate change, according to Climate Central, the weather science NGO. Five hundred and fifty pilgrims have died from heat-related illnesses in Saudi Arabia during this year’s Hajj – more than twice the number reported last year. Around 10 tourist deaths have been reported in Greece since the weekend and an atmospheric heat dome trapping hot air over New York, Chicago, Washington and Boston all week is roasting 270 million people with temperatures around 35 degrees – enough to cause heat cramps and exhaustion. Midwestern cities in Ohio have cancelled outdoor exercise while wildfires erupted in California and New Mexico. Last year was the hottest in human history, according to the National Oceanic and Atmospheric Administration. This year looks ready to beat that record.