IR Thermometer uses
Richard J Kinch wrote:
Point it up at the zenith of a clear, dark sky on a warm night. Brrr!
Inexpensive IR thermometers ignore water vapor (so people can use them
in boiler rooms full of steam), so this might also work on a warm
summer day.
Try it.
Don't misunderstand. You're reading the near-absolute-zero temperature of
outer space, through a thin veil of warmer air.
I understand that.
The integrated temperature is still below zero even on a warm night.
What's an "integrated temperature"? :-)
The clear night sky is a cold window.
Clear skies are, but water vapor and clouds absorb IR. So do windows...
"Ignore water vapor" is fantasy. Blackbody radiation is the same whether
it's a gas, liquid, or solid radiator.
Very wrong :-)
Nick
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