"Rising heat will kill more people by 2050, but people will also adapt. Researchers at the Climate Impact lab projected future 'mortality costs,' reflecting both the economic value of lives lost and the expense of adaptations such as air-conditioning. Geography, age distribution, and income all affect the projections. Many rich, colder cities will see net benefits but most of the world's population, in hot cities without the means to adapt, will see 'costs' -- and deaths -- rise."