To add my two cents to the discussion, there's a good debate in the economics literature on the rise of the sunbelt. There's some good evidence that it's not a preference for warm weather or sun that's driving growth in the sunbelt. Rather, the automobile and air conditioning led to increased productivity in the South up until the '80s, but now it seems that housing supply growth (due to ample land and lax zoning) is driving the shift in population. (
http://www.nber.org/papers/w13071)
One of the co-authors of that paper, Harvard urban economist Ed Glaeser, wrote up a nice summary for the NYTimes:
https://economix.blogs.nytimes.com/2...ulation-shift/
We also need to stop taking it for granted that people hate the cold and love the heat. In fact, it seems that people actually have a stronger aversion to heat than to cold. The "sweet spot" for the average American is around 65 degrees Fahrenheit.
http://davidalbouy.net/climatewelfare.pdf