#Widespread rain and snow will sweep through the central and eastern regions# #Guangdong will be colder than the New Year in the coming week# 【Landing on the ground into ice! The third round of large-scale rain and snow weather process since February this year is affecting the mainland, and from the night of February 18 to 19, there may be significant freezing rain in parts of central and northern Guizhou. Freezing rain is a meteorological disaster with strong destructive power, which has a greater impact on transportation, agricultural production, and power communication. How does freezing rain form? How harmful is it? Which places are most vulnerable? China Weather Network will answer you one by one.
Freezing rain disasters are distributed in both the north and south of the continent, and mountainous areas are more likely to occur
Freezing rain generally begins in November and continues until March of the following year, with January to February each year being the highest incidence of freezing rain.
On the mainland, frozen rain exists in both the north and south, showing a distribution pattern of more south and less north. In the south, most of Jianghuai, the northern and eastern parts of the southwest region, including High Altitude areas in Guizhou, Sichuan, Jiangxi, Hubei and Fujian, have experienced freezing rain. Among them, Guizhou is the area where freezing rain occurs most frequently, and Weining is the city most endangered by freezing rain, with an average of 41.6 days of frozen rain per year, with the title of "frozen rain town". The station with the largest number of frozen rain days on the mainland is Mount Emei in Sichuan, and from the observational data from 1991 to 2020, the average number of frozen rains will occur on more than 110 days per year.
In the north, there is no shortage of frozen rain, the eastern part of Inner Mongolia, the three northeastern provinces, Beijing-Tianjin-Hebei, Shandong, Henan and other places and the northern region of Xinjiang have been affected by freezing rain, but they are basically distributed in high-altitude areas such as mountainous areas.
Falling to the ground into ice? A picture to understand how freezing rain is formed
Frozen rain is the product of the intersection of cold and warm air, generally at this time, the cold air force between the two is stronger than the warm and humid air flow, the temperature near the ground plummets below the freezing point, and the warm air is lifted and becomes a cloud to cause rain. Although the name is frozen rain, its formation process is not simply freezing the raindrops, but the process of water vapor changing with the change of altitude.
At altitudes above two kilometers, water vapor is "frozen" and exists in the state of snowflakes or ice crystals. However, at lower altitudes of one to two thousand meters, controlled by the warm and humid air flow, the temperature reaches above the freezing point, while the near-ground temperature is below the freezing point, below the high-altitude temperature, forming an inversion layer. Ice crystals or snowflakes pass through the inversion layer, melt into water droplets, and when they reach the ground, they are quickly cooled into supercooled water droplets again, reaching the surface of objects, such as telephone poles, plants, trees, etc. Because the surrounding environment is below the freezing point, a layer of ice shell will be formed, which is called freezing rain in meteorology.
Rain glaze, rime stupid can't tell the difference between ice crystal tree hanging?
Rain is the product of frozen rain, that is, we often see ice crystal trees hanging, houses, bridges, trees covered by ice shells, like an ice age. In some areas of the south, people figuratively call it "lower ice ling", and in the north, it is called "ground oil". Freezing rain is not the only reason for the formation of rime, but freezing rain will definitely form a rime.
People often confuse rain glaze with rime, but the difference between the two is still very large. Both the rime and the rime are tree hangings, but the "material" is different. The rime is an ice shell formed by supercooled water droplets attached to the surface of the object, the surface is hard, and has a certain weight, and the density is larger; the rime is a milky white ice crystal deposit, more similar to frost, with small density and light weight. In addition to the form, the conditions for the formation of rime and rime are also different, the birth of rime is inseparable from the weather process, requiring the participation of cold and warm air, but rime is due to the surrounding environment for a long time low temperature, a large amount of water vapor condensation and formation.
Freezing rain weather is harmful This most comprehensive defense guide please put away
Freezing rain weather is harmful, often causing adverse effects on transportation, agriculture, electricity and other aspects. When the freezing rain comes, the tree hanging formed by falling on the surface of the object has a certain weight, which can cause the roof to collapse and the power pole and tree to be broken. In addition, road icing can also cause traffic travel to be greatly affected. In January 2008, there were four severe low-temperature rain and snow weather processes in the southern part of the mainland, which caused nearly 20 provinces (autonomous regions and municipalities) in the south of the mainland to suffer a rare freezing disaster in history, and transportation, energy supply, power transmission, agriculture and people's lives were extremely seriously affected.
In terms of traffic travel, when the freezing rain weather comes, the road is very easy to freeze, pedestrians should minimize travel, if you need to travel to do a good job of anti-slip measures, be careful and slow. If traveling by car, it is best to put snow chains on the tires, leaving enough braking distance to prevent the vehicle from slipping and rolling over. When freezing rain comes, the near-ground temperature is usually below freezing, and air transport is often affected by engine icing. Therefore, the relevant departments need to keep abreast of the weather forecast information, in case of freezing rain, check and confirm that the de-icing equipment can operate normally.
In agriculture, in addition to the attachment of ice shells that often damage crops, cold rainy weather also causes frost damage to crops due to low temperatures. Farmers and friends need to strengthen the management of field insulation, and timely pull up plastic sheds, plastic sheets and other covering items to protect crops. In addition, it is necessary to strengthen the regular inspection of vegetable greenhouses and livestock pens during the high incidence of freezing rain and repair them in time to prevent losses.
In terms of power communications, the rain glaze formed by freezing rainy weather often causes the poles to be crushed, and if the main power transmission lines are destroyed, it will cause large-scale power outages in the surrounding townships. In areas prone to freezing rain, it is necessary to strengthen the maintenance of the main power transmission system lines and key mobile base stations, and in case of freezing rain, timely organize personnel to carry out de-icing work.
Freezing rain weather is a kind of meteorological disaster with strong destructive power, which is distributed in the north and south of the mainland, and the above freezing rain defense guidelines need to be remembered, and advance defense measures need to be done. In addition, the China Weather Network especially reminds you that after the freezing rain, the temperature rises, and the ice covering the object falls off, which is very easy to hurt people. Therefore, pedestrians should pass through billboards, trees and buildings when they go out, so as to avoid being hit by falling ice from a high altitude. (Text/Jiang Yi Design/Chen Yujie Data Support/Li Liang Hu Xiao)
