How hot is too hot? How does “too hot” compare to “too cold?” We all have our own preferences and our own experiences, coloring the debate. Yet, it is worth noting that people, given their druthers in a modern society, with cost-efficient building and vehicle climate controls, choose warmer over colder climates. So “too hot” has meaning within the context of our ability to modify our experience of the local environment.

Back in the day, before the invention and wide availability of home and commercial property cooling systems, people who could escape the Desert Southwest heat did so by decamping for the summer to higher altitudes. Indeed, the wealthy citizens of Tucson, Arizona would trek up the nearest mountain to a seasonal community they named “Summerhaven.” They essentially closed up their primary residences, leaving a caretaker servant presence in the frying pan of the desert valley floor.

Because of the very low humidity, and the development of reliable municipal water systems, the denizens of the desert developed an energy efficient cooling system long before compressor-driven air conditioning became affordable. Informally, and sometimes derisively, called “swamp cooling,” evaporative cooling systems made dry summer heat into breathable and cool interior air.