How does humidity work? Right now, where I live it is 73% humity and 75 degrees and it doesn’t feel humid. In Costa Rica, the numbers were similar and it felt like I was in a shower. I know it has to do with humidity, temps, and dewpoint. I just can’t wrap my brain around it.
In: Planetary Science
Humidity is a percentage or how much water is in the air, relative to how much it can handle. At 100% it is as moist as it can get. At 0% there’s no water at all.
The trick is, how much water fits in the air varies by temperature. The hotter it is, the more water (as measured by counting water molecules or whatever, in a given amount of space) you can have in the air. So at 70 degrees it might be 100% humid… but as the temperature rises, the humidity percent goes down since the warmer air can tolerate more water.
Which leads us to the opposite effect – when the air *cools*. The dew point is just the temperature when humidity reaches/might exceed 100%.. obviously that can’t happen, and it forces water out of the air. You see things like the grass and your car are wet even though it didn’t rain. From the previous example, the dew point would simply be 69-70 degrees.
On any day that isn’t *dry*, grab a cold beverage out of the fridge and just let it sit. The can/bottle/container gets wet all on its own. That’s dew, because the temperature of said beverage is lower than the dew point, and so water forms on it. It’s also why air conditioners often drip water.
Your body sweats as a means of cooling itself. Sweat evaporates, which naturally cools the body from the evaporation itself, but it can only evaporate if the air is dry enough to accept that sweat as more humidity. On a hot day, or if you’re out in the sun exercising with 100% humidity, sweating doesn’t work. With a humidity of 90% it works very slowly. If you’re in a situation of high humidity and you’re sweating, yeah, it’s a problem and you’re gonna get soaked, but more to the point it means you’re not cooling yourself properly – take precautions as heat stroke is a real threat.
Latest Answers