|MadSci Network: Earth Sciences|
It's not that people sweat more in humid weather, it's that the sweat isn't able to evaporate as quickly. With the air already loaded with moisture, the perspiration on the skin cannot be absorbed by the air nearly as readily. Sweating is the body's reaction to heat, not humidity. On a hot, dry, breezy day, perspiration rates may be rapid, but it can also be drawn away from the skin quickly. On a cold, humid day, you'll notice that you don't sweat, unless you're working hard. Then the same thing happens - even though the temperature is low, the saturated air still makes the sweat linger, and you can get as soaked working hard at near-freezing temperatures as you can just lying in the sun when it's really hot.
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