Parts of the world currently inhabitable will become unlivable. In particular, Dubai, which is one of the most inhospitable places I've ever been on earth (combination of humidity + high temperature) - becomes lethal by 2100 in some projections - http://edition.cnn.com/2015/10/27/world/persian-gulf-heat-cl...
Hot temperatures are much more difficult to handle than cold temperatures for humans. With proper clothing/goggles/face masks, I've been downright cozy at -43 celsius in northern British Columbia - spent hours completely comfortable. In Dubai, on a hot, humid day in September, I can manage maybe 15 minutes of exertion before I have to escape back to air-conditioning.
Hot temperatures are much more difficult to handle than cold temperatures for humans. With proper clothing/goggles/face masks, I've been downright cozy at -43 celsius in northern British Columbia - spent hours completely comfortable. In Dubai, on a hot, humid day in September, I can manage maybe 15 minutes of exertion before I have to escape back to air-conditioning.