|Evaporative cooling at a local Phoenix emporium during my layover.|
Many hot dry states like Arizona, Nevada, Southern California, New Mexico utilize water misters at restaurants. shops and pubs. Why? The process of evaporation requires heat.
Because energy is needed to overcome the molecular forces of attraction between water particles, the process from a parcel of water to a parcel of vapor requires the input of energy causing a drop in temperature in its surroundings. Translation...the air cools.
It's why you feel cool when you get out of a shower or pool even on a hot day. It's why you sweat. The sweat evaporates causing your body to cool.
So the nearby air is cooled from the mist evaporating into the dry air. It also gets on your body and it causes cooling. As well, it also increases the relative humidity making you feel more comfortable. Remember we are talking near desert air with very low relative humidities. It's why aircraft are stowed in these desserts...it imposes less wear and tear on the aircraft.
When I taught Weather 101 for new pilots, I asked the question....does rain reduce visibility? (I'd always ask smart ass questions knowing full well they would not get them.
Cruel....I know). Actually, rain refracts but it does not reduce visibility. It's the fog in between the rain droplets formed from evaporation which reduces the visibility. It's called rain induced or frontal fog.
So while we capitalized on happy hour...meteorology was at play. Actually, I also asked my weather 101 class why a cloud forms in the neck of a freshly opened beer (coke if you don't drink) bottle? It's due to adiabatic expansion. You are releasing a compressed gas, expanding it and thus cooling it. Much like how clouds are formed.
All of this meteorology talk is making me thirsty.
So there you have it. Meteorology on my last layover. :))))