The perfect water temperature

posted: October 4, 2019

tl;dr: The hot, dry summer in the Valley of the Sun has some unexpected pleasures...

Yes, summers are quite hot in the Valley of the Sun (although it is usually a dry heat), but they have certain advantages. One of them is that outdoor pools heat up to what I consider to be the perfect temperature.

All my life prior to moving to Arizona, whenever I’ve gotten into a pool, pond, lake, stream, river, or ocean to do some swimming or merely splash about, I’ve experienced a bracing chill upon first encountering the water. Sometimes I gradually wade in, slowly acquainting my lower extremities with the cool water; at other times I resign myself to the full body shock of jumping all in at once. Soon the body becomes accustomed to the water temperature, unless it is especially cold. There is another episode of chills later, upon exiting the water, as the cool air reacts with the water beading on the body’s surface. A towel is a must, to remove the water and provide some shelter from the cool air.

At a certain point during summer in the Valley, this experience transforms. The water in the pools heats up to the point where there is not the slightest bit of chill upon entering it, with nary a goosebump to be found. The water is neither too cold nor too hot; as Goldilocks would say, it is just right. An even more wondrous thing happens upon exiting the pool into the even warmer, dry air: again there is not the slightest bit of chill nor a single goosebump. A towel is not needed, either to dry off or to warm up: the water quickly evaporates, without inducing a chill.

After more than five decades of being chilled upon entering and exiting swimming pools, I was amazed the first time this happened to me. Swimming pools do not have to induce chills upon entering and exiting; one can instead enter and exit them seamlessly, without a shock to the system. This was an unexpected side benefit of the well-known Arizona summer heat.

For most of the existence of humankind, our species has known how to create heat, primarily by burning things: wood, coal, oil, natural gas. This has the unfortunate side effect of raising carbon dioxide levels in the atmosphere, leading to greenhouse effect warming. This technology, crude as it is, has enabled humans to live in cold environments where there was sufficient fuel to produce localized heat.

Yet it has been only recently, through the development of refrigeration and air conditioning, that humankind has had the technology to enable us to live in hot environments that require localized cooling. This has obviously led to major population growth in Arizona and other so-called Sun Belt states. If we are able to generate the electricity needed to power refrigeration and air conditioning equipment without burning fuels, we’ll have enabled humans to live comfortably in both hot and cold environments without putting greenhouse gases into the atmosphere. Arizona, because of its plentiful sunshine, is actually well-positioned to achieve this goal. I am optimistic.

Alas, summer 2019 is over and, even in the Valley of the Sun, it has started to cool down a bit. The water in the neighborhood pool has cooled slightly, so there is a slight chill upon entering it. At some point in the months ahead, since the pool is unheated, it will be too unpleasant to enter. Unheated pools in Arizona are not always at the perfect temperature year round, but they do achieve that ideal state during the hot, dry heat of summer.