Guangxi Xiangdu Frost Festival Composition

Since there is frost when there is frost (sometimes there is no frost, it is called black frost), so autumn frost and spring frost are collectively called frost.

Frost solar term means that the weather is getting colder and frost begins to fall. In southern areas with latitudes that are more southerly, the average temperature is around 16°C, and there are still three solar terms left before the first frost date. In the river valleys of southern South China, frost can only be seen in the middle of winter. Of course, even in places with the same latitude, due to differences in altitude and terrain, the temperature and humidity of the air close to the ground are different, so the first frost period and the number of frost days are also different. During the frost season, the cool autumn wind has blown into the flower city of Guangzhou. The average temperature in northern Northeast China, eastern Inner Mongolia and most of northwest China is already below 0℃.

"Frost begins with frost" reflects the climate characteristics of the Yellow River Basin. In terms of frost days throughout the year, some places on the Qinghai-Tibet Plateau have frost and snow even in summer, with more than 200 frost days per year, making it the place with the most frost days in my country. Eastern Tibet, southern Qinghai, Qilian Mountains, Western Sichuan Plateau, northwest Yunnan, Tianshan Mountains, Altai Mountains, western mountainous areas of Northern Xinjiang, Northeast China and eastern Inner Mongolia have more than 100 frost days per year. The areas south of the Huaihe River and Han River and the eastern slope of the Qinghai-Tibet Plateau have more than 100 frost days per year. The vast area to the east has less than 50 frost days, south of 25° north latitude and the Sichuan Basin only has about 10 days, the south of Fuzhou and the coastal areas of Guangdong and Guangxi have an average annual frost day of less than 1 day, while Xishuangbanna, Hainan, southern Taiwan and the South China Sea Islands It is a place where there is no frost.

The first frost in autumn is called the first frost. The earlier the first frost occurs, the greater the damage to crops. The first frost in various parts of our country is gradually delayed from north to south, from mountains to plains. Except for areas with frost throughout the year, the earliest frost is in the northern part of the Daxinganling Mountains, usually at the end of August; the first frost is mostly in September in most of the Northeast, Inner Mongolia and northern Xinjiang; in early October, frost has already appeared in Shenyang, Chengde, Frost can already be seen from Yulin, Qamdo to Lhasa in early November from Shandong Peninsula, Zhengzhou, Xi'an to northwest Yunnan; frost will not start to appear until early December in areas around 30° north latitude in eastern my country, Hanshui River, and Yunnan Province at around 2° north latitude; It is already early January after the New Year when frost occurs in areas from Xiamen and Guangzhou to Baise and Simao.

Frost is the condensation of water vapor on the ground when it encounters cold weather, so frost does not mean falling frost, but means that the weather is cold and the ground will produce the first frost. From a scientific perspective, the saying "dew turns into frost" is inaccurate. Frozen dew is formed by freezing dew drops into small, hard ice beads. Frost refers to the freezing damage to crops caused by a sharp drop in temperature. The damage temperature varies depending on the crop, variety and growth period. To form frost, the temperature of the ground or surface must drop below 0°C, and The water vapor content in the air in the underlying formation must reach a certain level. Therefore, when frost occurs, frost does not necessarily occur, and when frost occurs, frost does not necessarily occur. However, because the temperature is already relatively low when frost occurs, if it continues to cool, it will easily lead to frost.

"Frost kills all grass", plants that have been hit by severe frost have no vitality at all. This is because the liquid in the plant freezes into ice crystals due to frost, proteins precipitate, and the water in the cells leaks out, causing the protoplasm to become severely dehydrated and deteriorate. "The wind, the sword, and the frost are fiercely pressing each other" shows that frost is ruthless and cruel. In fact, although frost and frost are closely related, it is "freeze" and not "frost" that harm crops. Someone once experimented: Put two leaves of a plant in boxes with the same low temperature. One leaf was covered with frost, and the other leaf was not covered with frost. As a result, the frost-free leaf was severely damaged, while the frost-covered leaf was only Minor signs of frost damage. This shows that frost can not harm crops. On the contrary, when water vapor condenses, it can also release a large amount of heat. When 1 gram of water vapor at 0°C condenses into water, the heat of vaporization is 667 calories, which will turn heavy frost into light frost. , light frost turns into dew, avoiding freezing damage.

Instead of saying "frost kills all grass", it is better to say "frost kills all grass". Frost is a sign of cold weather, and freezing is the enemy that kills crops. Since there is frost when there is frost (sometimes there is no frost, it is called black frost), so autumn frost and spring frost are collectively called frost.