We're going to find out soon enough.

Almost half of the global population will be living with extreme heat by 2050 if the world reaches 2C of global warming above preindustrial levels, according to a University of Oxford study published in January. India will have the largest affected population, says urban climatologist Radhika Khosla, an associate professor who co-authored the study.

People shift to working indoors, and for outdoor work at night. I’m sure economies like the Middle East and Palm Springs already have this sort of thing worked out.