As the saying goes, snow does not freeze into snow. How to explain this scientifically?

What is the relationship between snow or melting snow and environmental temperature in real life? On the other hand, the physical laws of ice, snow and water conversion remain unchanged, but due to the different temperatures in the morning and evening of a day, the temperatures in different places (such as two places and white light) at the same time are also different. In addition, snow and dirty eyes have different abilities to absorb heat. Even if the ambient temperature is higher than 0oC, there is a process of eye melting, and there is also the influence of wind speed and humidity. This makes the problem of "whether it snows or not cold" very complicated. To scientifically judge whether it snows, we must first make clear what is the first snow and what is the melting snow. But at this time, the ground temperature is always above 0oC. So the snow melted as soon as it landed. Although it is snowing, the snow will melt with it, and the temperature is always above 0oC. Even if this situation is considered as snow, will the snow melt?

According to the data of the snowfall process in Nanchang in recent years 10, it is calculated that the average maximum temperature in snowy days is -2.76oC, the climate temperature in uniform snow is -0.63oC, the average maximum temperature is 3.2oC, the average minimum temperature is-1.8oC, and the average temperature is 0.7oC. Generally speaking, the temperature in snowy days is lower than that in snowmelt climate.

So the so-called "snow is not cold" is not established in physics. It's snowing, and the climate is lower than that in China. Why do you say it snows, but it's not cold? In addition to the negative explanation at the beginning of this article, the author also collected the following explanations. 1, boring insulation theory; 2. Hua Xuefeng said; 3. Radiation cooling theory; 4. Correct mistakes and speak positively. Below, let's analyze these explanations one by one. First, stuffy heat preservation theory: This concept holds that when it snows, the air humidity is low and stuffy, and the heat preservation function of air and clothes is relatively good. When it snows, the air humidity is relatively high, and the air is thermoelectric, which makes people feel cold.

The warmth of clothes is also worse. Therefore, this slight humidity change will not produce obvious "eye, cold, snow and cold" effects. It is reasonable to help the above claims, but the basis seems to be still insufficient. Hua Xuefeng said loudly. "When the snow melts, the wind blows hard and looks very cold." According to the recent climate statistics in Nanchang, the average wind speed in snowy days is 2.3m/s and 1. 1m/s ... So this theoretical basis is insufficient. "Snowy days are usually the sun, and there are no branches. In this way, the heat on the ground is easy to be lost at night, so the lowest temperature in snowy days is lower than that in snowy days. " According to Nanchang's calculation, the average temperature in snowy days is -2.76oC, the average temperature in snowy days is-1.8oC, the lowest temperature is still snowing, and the sky is very low, so this theory is not valid. Fourth, the correction said: "The eyes are not cold, the eyes are not cold. Mainly to correct the ancient theory that it is still cold in order to pay attention to snow. In fact, snow is still colder than flower snow. " According to this revision, there are many climate proverbs in China, which are "18 autumn tigers are fiercer after beginning of autumn".