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.
The technology was very simple. Drip water over a fiber (straw then synthetic) pad, possibly with a small pump regulating the flow. Spin a fan to draw dry exterior air through the wet pad. The evaporation consumes heat energy. So, the fan blows cool moist air into the home or business.
The system depends on a significant difference between ambient humidity and the air being blown. So, you actually got a cooling advantage if your house was a bit leaky, rather than sealed air tight. Indeed, homes and apartments built to modern national specifications need to have a window cracked open for evaporative cooling to be its most effective.
A group of Arizona desert dwellers relocated to the Iraqi desert as summer approached in 2003. Unlike almost all other members of our merry band enjoying an all-expenses-paid Iraqi Vacation (hat tip National Lampoon), we knew exactly what those weird boxes on building roofs were. My supply officer quickly organized a run into the local economy and procured enough simple cooling units to make the days and nights bearable for the troops under my command.
Take a simple galvanized metal box, with three slatted sides holding straw evaporative pads. Spin a drum fan in the middle of the box, with the thrust pointing towards a large round hole in the fourth side. Mount and seal it up against an open window. Place a 55 gallon water drum above the cooling unit so you get gravity feed. Now you have effective cooling well inside the energy budget of the unit’s standard issue generators.
Sadly, the powers that be used the excuse of “taking care of Joe” to justify an outrageous abuse of the public purse, with massive expenditures on regionally leased generators and air conditioning systems. All of this required additional fuel, maintenance, and transportation, increasing risk to “Joes.” But senior people from temperate climates eventually got the comforts of their homes in an alien desert.
Until the leased equipment was distributed, our small desert native contingent enjoyed the distinction of taming an increasingly scorching summer. We stored, issued, transported and tested fuel, to the tune of a million gallons a day through-put. Our truckers improvised cooling on the road, making water drinkable after hours in convoy.
Take a long boot sock. Slide a water bottle into it. Soak the sock and tie it to the exterior mirror. The wind generated by the truck racing through the desert evaporates the water in the sock, keeping the water bottle at a drinkable temperature. Repeat as needed.
Why not just keep the water in the crew cab? Because military trucks had no crew-cooling systems, just heaters. So, soak your shirt before you put on your body armor or soak it with sweat as the sun turns the cab into a solar oven. It certainly felt like an oven. Indeed, the air temperature eventually felt like someone had opened an oven door.
Over a decade earlier, I had the additional duty of mess (food service) officer. I had also worked food service summer jobs. So, I had “160° F” embedded in my memory. That is the standard rule-of-thumb safe serving temperature. Whip out your food thermometer, sheathed in your shirt pocket, and check the food on the serving line.
Understand, home and regular office thermometers are built for “normal” ranges. “Normal” would be the expected temperatures in the United States. They are not marked as such. So, the day came when I was standing outside my headquarters with several staff members and looked at a thermometer hung in the shade. It read 150° F.
“That’s almost serving temperature!” I exclaimed. Eventually, we found the true temperatures were “only” around 126° F. If you are a steak aficionado, you may recognize 126° F as one of the values for “medium rare.” It was a rare service experience, indeed!Published in