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https://medium.com/the-infinite-universe/new-experimental-wet-bulb-globe-temperature-to-help-us-know-when-it-is-safe-to-brave-the-heat-710f2d68c002>
"Global warming means that each summer is hotter than the last and each year
deadly heat spreads further north. Yet, heat in itself isn’t what kills. It is
rather when the weather interferes with the ability of the human body to get
rid of heat. This is called the wet bulb temperature.
Put simply, the wet bulb temperature is the temperature down to which something
can be cooled by evaporative means, i.e., by water evaporation. You measure it
by wrapping a wet cloth around the mercury bulb of an ordinary thermometer. As
long as the cloth stays wet, it will carry heat away from the thermometer,
similar to how sweat carries heat away from the human body.
Although digital solutions are preferred nowadays, a simple device called a
sling psychrometer can tell the wetbulb temperature.
While the absolute temperature is a factor in wet bulb temperature, so is
humidity. The more humid it is the less water the air can absorb. Once you
reach 100% humidity, the air cannot absorb anymore and evaporative cooling
ceases. At that point, other forms of cooling such as convection currents and
radiation continue as long as your body is warmer than its surroundings. These
are, unfortunately, far less efficient.
If the body cannot get rid of heat efficiently, the core temperature rises and
you get heat stroke which can lead to death.
Wet bulb temperature is always lower than the actual temperature, unless it is
100% humid, in which case it is the same. And it can be deceptive how safe the
heat actually is."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
