human population could be exposed to periods of life-threatening climatic conditions arising from coupled impacts of extreme heat and humidity by 2100 . Cities in mid-latitudes are potentially subject to twice the levels of heat stress compared with their rural surroundings under all RCP scenarios by 2050, for example Belgian cities . A disproportionate level of exposure exists in subtropical cities subject to year-round warm temperatures and higher humidity, requiring less warming to exceed 'dangerous' thresholds, for example Nairobi  and São Paulo . It is expected that more than 90% of the 300 million people who will be exposed to super- and ultra-extreme heatwaves in the Middle East and North Africa will live in urban centres , while the
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report