Popular blogger Dmitry Sevastyanov easily explained a seemingly surprising paradox: why American schoolchildren (as can be seen from a photograph from Wisconsin) surprisingly many walk in the cold without hats and in some sweatshirts, while Russian students are usually wrapped up. The point, according to the author, is not only in temperature, but also in some other, equally important factors, since weather in general is an extremely complex concept, and can differ even in one small region, depending on the terrain or the movement of air masses.
And in fact - American schoolchildren look frozen, they hide their hands and walk shriveled. It's just that in America, school buses take children right from home, so they don't have time to chill too much. And the main thing: the concept of "weather severity". At the same air temperature (unless, of course, it is minus 60 or plus 50), it can vary greatly depending on humidity and wind strength. At minus 15, strong winds and high humidity, anyone, even the most hardened person, will freeze. In Wisconsin last week, when these photos were taken, the humidity averaged 60%. But in many regions of Russia it is significantly higher. For example, in Kazan, it is 90-100% all winter long, so even at minus 5 without gloves and warm clothes, you will instantly die. And it is unlikely in such conditions, even to the bus, American schoolchildren ran in some sweatshirts. Pneumonia would be provided!
The thing is that the air has a very weak thermal conductivity, so even the air gap in the double window will protect the home from the cold. But water is a very good heat conductor, and therefore it will quickly heat a person in the heat, for example, in Vietnam, and instantly cool it down in the frost in Kazan or St. Petersburg. The higher the humidity, the stronger the wind, the more severe any cold is. That's the whole answer.