Roof lakes will become an important air-conditioning method.



Waldemar Kaempffert : Science writer
In 1950, Popular Mechanics printed an article forecasting what everyday life would be like in AD 2000, including such luxuries as the use of inches of water on roofs to cool houses.


Waldemar Kaempffert, "Miracles You’ll See In The Next Fifty Years", Popular Mechanics. Feb 1950.


http://blog.modernmechanix.com/miracles-youll-see-in-the-next-fifty-years/5/#mmGal