Frozen rain is often heard in weather forecasts in an area. How did the freezing rain come? Why isn't it snow? Today, let's learn about the freezing rain。
Frozen rain and rain
Frozen rain consists of a mixture of ice water, which collides with immediately frozen precipitation at temperatures below 0°c, and is a catastrophic weather seen at the beginning of early winter or the beginning of spring. Raindrops below 0°c are able to remain cold in air at a temperature of slightly less than 0°c and have the same appearance as ordinary raindrops. When they reach objects below 0°c, they freeze immediately to a smooth and transparent ice layer known as rain。
Causes of freezing rain
The formation of “frozen rain” and the smooth landing of cooling drops to the ground often depend on specific weather conditions: the atmosphere structure of the air layer, which is about 2,000 metres near the ground, is slightly below 0°c; the air layer, which is between 2,000 and 4,000 metres above 0°c, is warmer; and the upper layer, which is below 0°c, makes the perfluorinated water droplets, crystals and snowflakes in the upper clouds, all of which fall into a warmer layer, becoming liquid droplets. It's going down again, and it's going into the middle of the freeze. When it continues to decline, preparing to freeze, it has reached cold objects in the form of cooling, creating solid “frozen rain”。
Frozen rain features
Climate characteristics
The thickness of the freezing rain is typically 10-20 mm and the thickest is 30-40 mm. When freezing rains occur, the wind is often greater。
Time features
Most of the freezing rains occurred in the first half of january and more than a month in the middle of february, starting with early and late north and south, with early and late mountainous areas and the opposite end date. In high-lying mountainous regions, freezing rains begin early and end late, with a slightly longer period. In the case of the yellow hills, the freezing rain generally began in early november and ended in early april of the following year for five months。
Geographical characteristics
Frozen rains are frequent in mountainous and lake areas; more and less in the south; and more and more arid in the humid areas
Less; mountains are larger than plains and the highest. According to statistics, the cold rain in the river basin was seen two to three years in the direction of the river and seven to eight years in the south of the river. In the mountains, however, there is a large difference between valleys and hilltops, and in parts of the mountains there is virtually no freezing rain, which occurs almost every year at the height of the mountains。
The hazard of freezing rain
Frozen rain is a catastrophic weather, with massive freezes and accumulations that can break power lines and telephone lines, severe freezing rains that crush houses, and when planes fly in clouds with cold drops, mr. Tan's geo-working room consolidates wings and propellers and accumulates water, causing accidents affecting the aerodynamic performance of aircraft。
Test link
I. Single topics
Freezing rain is a weather phenomenon in winter. When raindrops fall from the air, because of the low temperature near the ground and the freezing of a thin layer of ice on the surface of the ground, this weather phenomenon is called “frozen rain”. Read the forecast of our frozen rain zone on a given day and finish the next issue accordingly。
The main reason for the high incidence of freezing rain in the graphic area is
Air convection b. Cyclone control
C. Warm front affects d. The terrain
References
1. D
Test analysis: the cold air from the north-west and the warm and wet air from the indian ocean collide with the low surface of the cloud highlands due to the obstruction of the cloudy highlands in the early winter, the late winter and the early spring, forming a quasi-silient front, indicating areas on the side of the quasi-silient cooling band, with low temperatures near the ground and prone to freezing rain。
The cause of a weather disaster。
[knowledge expands] frozen rain and its causes:
1. The phenomenon: frozen rain is a weather phenomenon seen in the early winter or the early spring of the winter. When the colder air is exposed to a warm and wet flow southward, the cold air is inserted like wedges below the warm air, temperatures in the near-earth layer are drastically reduced to below zero degrees, wet warm air is lifted and cloudy. When raindrops fall from the air, due to the low temperatures on the near surface, a thin layer of crystall ice is frozen on utility poles, trees, vegetation and the surface of roads, a phenomenon known by weather as “frozen rain”。
2. Causes: in the south of china, early winter or late winter, when warm air comes to the fore and warmer air is strong, air temperatures are lower (less than 0°c) near the ground level, with air or clouds above 0°c on top and ice crystals below 0°c on top. The vertical structure of the atmosphere is cold above and below. The snowflakes that fall from the crystals melt into raindrops as they pass through the warmer layer, and when it enters the cooling zone near the ground, the raindrops cool quickly, and the temperature has fallen below 0°c, creating a cold drop, or “frozen rain”. When the freezing rain reaches the cold surface, it freezes and becomes what we see
3. Time: most of the freezing rains occur in the first half of january to the first half of february and more than a month in mid-february, starting with early and late north and south, with early and late mountains and plains and ending days. In high-lying mountainous regions, freezing rains begin early and end late, with a slightly longer period。
4. Distribution: the highest incidence of freezing rain in the country is found in guizhou province, followed by hunan, jiangxi, hubei, henan, anhui, jiangsu, shandong, hebei, shuxi, gansu and southern liaoning, where the mountains are more mountainous than the plains and the highest。
5. Disasters: when electrical cables are frozen, the effects of cold contractions, combined with the weight of frozen rain, are severed. In some cases, lined poles were pulled down, disrupting telecommunications and transmission. Road traffic is hampered by ice on the ground and traffic accidents have increased. Daejeon is frozen and will freeze cold winter wheat or seedlings of crops planted in the early spring. In addition, freezing rains can cause extensive damage to juvenile forests, frozen fruit trees, etc。
Ii. Comprehensive issues
Read our map of frozen rain in the south and answer the following questions (12 minutes)
2. The provincial abbreviations for the main distribution of freezing rain are b, c
3. A region is higher than the latitude of the freezing rain zone, and the historical impact of the freezing rain on a is largely due to the fact that
With regard to the cause of the freezing rain, the error in the description is
The increase in winter winds in the country, affected by the la niÑa phenomenon, has caused long periods of rain and snow weather in the south of the country
B. The cooling gas stream in the north meets the hot and wet current in the south and creates cold weather
C. El niÑo's early summer wind landing was the main cause of this freezing rain
In january, the sun was launched directly in the southern hemisphere, with a small solar altitude in the southern part of the country and a sudden drop in temperature to form a freezing rain
5. In addition to freezing rain, what are the meteorological hazards that characterize agricultural development in the region
The majority of the province of 6. B is located in the terrain, characterized by multi-distributional landscape types, mainly geological formation。
Frozen rain is the immediate freezing of precipitation when ice water mixtures collide with objects at temperatures below 0°c, and is a catastrophic weather in our country during the winter. On 29 january 2015, guizhou was hit by the first widespread cold rain weather this year, with freezing rain and freezing electricity lines in 20 counties and municipalities。
(1) briefly describe the hazards of frozen rain in guizhou。
(2) briefly describe the measures taken to combat freezing rain。
2. 黔 or 贵, 湘 (2 minutes)
3. The terrain of the basin is blocked in the north by the qinqing great baa mountain and is less affected by winter winds. (2 minutes)
4. Cd (2 minutes)
5. Low-temperature rain, summer floods, drought (2 minutes)
6. Cloud highlands; rugged terrain; caste landscape; water erosion (4 minutes)
Question analysis:
2. Based on the geographical location shown in the figure, the prefectures with the main distribution of the freezing rain are known as b and c。
The area of a is higher than the latitude of the freezing rain zone, and the primary reasons for the historically minimal impact of the freezing rain on a are: a is the basin terrain, the northern part is blocked by the qinqing baa hill, and is less affected by winter winds。
4. This freezing rain was caused by the prolonged rainy and snow weather in the southern part of the country, caused by the intensification of winter winds; the cooling air in the northern part fell southward and met with the warm and humid gas in the northern part of the south, creating cold weather. So this topic chooses the cd option。
In addition to freezing rain, agricultural development in the region includes low-temperature spring rains, summer floods and drought。
6. Province b is the province of guizhou, most of which is situated in the topography of the yunju plateau and is characterized by rugged terrain and multi-distributed caste landscape types, which consist mainly of water erosion geological formation。
Point of view: provinces of china; main factors affecting climate。
Point assessment: the issue is not difficult and requires a comprehensive analysis of the causes of climate impacts in the context of regional knowledge。
7.(1) loss of life or injury; 2 property losses: freezing of crops or even crop failure; extensive destruction of juvenile forests, frozen fruit trees, etc. By freezing rain. Social instability: disruption of telecommunications and electricity. Road traffic was hampered by ice on the ground and traffic accidents increased. Environmental damage to resources. That's all right. That's four points
(2)1 strengthen monitoring and forecasting of freezing rain disasters. Increased public awareness and awareness of disaster prevention and mitigation. 3. Strengthening winter agricultural crops against cold. Establishment of a sound policy and regulatory framework for disaster reduction. 5 preparation of contingency plans. Improving the rescue system. Six points to three, that's all
Question analysis:
(1) the risks to humans caused by the freezing of rain should be captured in two main areas: loss of life and injury and loss of property. Property losses can be answered in both agricultural and social terms. Frozen rains cause crop injuries and reduced production of cash crops; they affect telecommunications and grid facilities and the normal production of people's lives; road surfaces are affected by freezing rains, which can cause traffic accidents; and some biological resources and living environments are destroyed。
(2) natural disasters should focus on three different phases before, during and after disasters. The modules are as follows: pre-disaster monitoring and forecasting, awareness-raising, public awareness of disaster prevention and mitigation, winter agricultural crops against the cold, disaster policy and regulatory frameworks for sound disaster reduction and contingency planning, and post-disaster response systems。
The threat and the response to natural disasters。
Ping's on the subject of temperature
