Xinjiang is snowing and having snowball fights in August. Why does it snow in August?

Subconsciously, everyone thinks that it only snows in winter. In fact, there are differences between the north and the south. When it snows in the north and people wear winter coats, people in the southern islands still wear short clothes and short sleeves.

Why is this? xiangnel will decipher for you: Why does it snow in August?

Snow

Snow is precipitation composed of a large number of white opaque ice crystals (snow crystals) and their polymers (snow masses).

Snow formation conditions

Water vapor saturation

The maximum amount of water vapor that the air can contain at a certain temperature is called the saturated water vapor amount. The temperature at which air reaches saturation is called the dew point. When saturated air cools to a temperature below the dew point, excess water vapor in the air turns into water droplets or ice crystals. Because the saturated water vapor content of the ice surface is lower than that of the water surface, the water vapor saturation required for the growth of ice crystals is lower than that of water droplets. In other words, water droplets must grow when the relative humidity (relative humidity refers to the ratio of the actual water vapor pressure in the air to the saturated water vapor pressure of the air at the same temperature) is not less than 100%; as for ice crystals, the relative humidity is often less than 100% It can also grow over time. For example, when the air temperature is -20°C and the relative humidity is only 80%, ice crystals can grow. The colder the temperature, the less humidity required for ice crystals to grow. Therefore, in high-altitude and low-temperature environments, ice crystals are more likely to be generated than water droplets.

There are condensation nuclei in the air

Some people have done experiments. If there are no condensation nuclei, the water vapor in the air will be supersaturated to a relative humidity of more than 500% before it can condense into water droplets. But such a large supersaturation phenomenon does not exist in the natural atmosphere. Therefore, without condensation nuclei, it would be difficult to see rain and snow on our earth. Condensation nuclei are tiny solid particles suspended in the air. The most ideal condensation nuclei are those material particles that absorb water the most. For example, particles of sea salt, sulfuric acid, nitrogen and other chemicals. That’s why we sometimes see clouds in the sky but no snowfall. In this case, people often use artificial snowfall.

Is it true that it snows in August?

As evidenced by pictures, this is indeed true. As can be seen from the pictures provided by netizens on Weibo, the man on the left taking the photo above is wearing short-sleeved shirts, and the man wearing a shirt in the upper right corner of the photo is also wearing short-sleeved shirts. Due to the difference in temperature between morning and evening in Xinjiang, other people were wearing jackets, which is more in line with Xinjiang’s climate characteristics in August.

Why does it snow in August?

Altitude reasons

High altitude areas are more prone to snow. Generally speaking, the higher the altitude, the lower the temperature. Because the main direct heat source of the tropospheric atmosphere is the ground, the farther away from the ground, the less ground radiation we get and the lower the temperature. For every 100 meters of altitude increase, the temperature drops by 0.6 degrees Celsius (vertical temperature lapse rate).

Although the temperature in August is the highest in the whole year, the temperature in high altitude areas will also be lower.

Based on the characteristic that for every 100 meters of elevation, the temperature drops by 0.6 degrees Celsius, we conclude that

at an altitude of 1,000 meters, the temperature drops by 6 degrees Celsius

at an altitude of 2,000 meters , the temperature dropped by 12 degrees Celsius

At an altitude of 3,000 meters, the temperature dropped by 18 degrees Celsius

At an altitude of 4,000 meters, the temperature dropped by 24 degrees Celsius

At an altitude of 5,000 meters, the temperature dropped by 30 degrees Celsius

At an altitude of 6,000 meters, the temperature dropped by 36 degrees Celsius

At an altitude of 7,000 meters, the temperature dropped by 42 degrees Celsius

At an altitude of 8,000 meters, the temperature dropped by 48 degrees Celsius

< p>The place where the snow occurred is located in the Duku Highway Tunnel. The spectacular and winding Duku Highway passes through the "Tielimai Tida Ban" at an altitude of 3,700 meters in the Tianshan Mountains. The Hasilgundaban Tunnel, with an altitude of 3,390 meters, is the highest tunnel in China. There is also a 100-meter snow-proof corridor built on the highway to prevent avalanches of snow from the cliffs from falling into deep ditches beside the highway.

Cold air and humidity

This can be said to be related to the greater latitude. In low latitudes, cold air has a smaller impact, while in high latitudes, cold air has a greater impact on temperature.

According to information provided by the Dalian Meteorological Observatory forecaster, the local area has been affected by a strong cold air, and the temperature has generally dropped. There is widespread rainfall in the surrounding areas and short-term convective air.

?

So, as long as the conditions for snow are met, it has nothing to do with the month. When it is summer in the northern hemisphere, it is already winter in the southern hemisphere. While the summer is scorching in the plains, Mount Everest is still covered with snow.