Wait, what?: If it's "totally doable" for me to live in a 90 F. degree house right now, how exactly would a 63 F. world be too hot for my grandchildren?

Americans urged to end their reliance on air conditioning as heat wave endures - Winnipeg Free Press

And it's a vicious circle: the reliance on A.C. is contributing to global warming, Cox says, which in turn creates more of a demand for it.

Americans have to wean themselves off a modern-day phenomenon that Cox says has not only affected population and electoral maps in the U.S. — more people have moved south knowing they can stay cool 24/7— but is also contributing to obesity rates by keeping them indoors and inactive.
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"I am indeed surviving without A.C.," said [Meredith Modzelewski] who works for an organization that helps large school districts serve healthier, sustainably produced food to students.

"I think it's totally doable for many people. I like having a climate-controlled environment while I am at work. But at home, I enjoy feeling the real temperature, and it makes the heat easier to deal with overall when you allow your body to be used to it and to truly feel it," she said.