I was told that certain regions of the world are very humid like US south or Japan. However this doesn't seem to be the case...? I wouldn't describe my climate in Poland as humid yet it's at the top of the scale and higher than those aforementioned

So you just now realized americans are serial embellishers and japs are deluded?

>>213448433 (OP)
This is a map of relative humidity, i.e. the amount of water in the air over the max amount of water that the air can hold. The hotter the temperature is, the more water that the air can hold, so even though the relative humidity in the American south might be lower than in Poland, the amount of water in the air (the absolute humidity) is likely higher since the temperatures are higher.

>>213448597
i was told that this is the reason japanese people have only AC and no insulation whatsoever on their houses, because of the humidity and mold risk and their houses need ventilation instead of insulation hence they wear clothes indoors during winters and use space heaters

I can't speak for Japan and whatnot, but the humidity of the southeast here is usually stated in contrast to that of the southwest, specifically in conversations about wet heat vs dry heat. Most people care about humidity as it relates to the (in)ability to cool off, and the southeast is both hot and humid. Also, >>213448667

>>213448433 (OP)
>Many times, relative humidity can be misleading. For example, a temperature of 30 and a dew point of 30 will give you a relative humidity of 100%, but a temperature of 80 and a dew point of 60 produces a relative humidity of 50%. It would feel much more "humid" on the 80 degree day with 50% relative humidity than on the 30 degree day with a 100% relative humidity. This is because of the higher dew point.

for reference

>>213448433 (OP)
Humidity only becomes an unbearable problem on hot climate countries.