Case Analysis —— Low temperature and freezing disaster in southern China at the beginning of the year

(1) Overview of low temperature and freezing disasters in 2008

After 65438+ 10/0 in 2008, the weather situation in China has changed obviously. From sunny, warm and rainy weather since last winter to low temperature and rainy weather. From 65438+ 10/0 to February 2, the continuous low temperature, rain, snow and freezing weather caused great disasters to 20 provinces (autonomous regions and municipalities) such as Hunan, Hubei, Anhui, Jiangxi, Guangxi and Guizhou. Cold damage mainly caused large-scale water and power cuts, traffic jams, a large number of passengers stranded in roads, stations and airports, and the long-term saturated logistics and energy systems collapsed in extreme environments, resulting in 129 deaths and direct economic losses exceeding15 billion yuan (Figure 8- 1).

Figure 8- 1 2008 China Low Temperature and Freezing Disaster

(According to, 20 1 1 May 1)

The specific disasters are as follows:

1) power system: continuous heavy snow and freezing rain caused cable breakage and tower collapse, resulting in large-scale power outages in some areas of the above provinces (autonomous regions and municipalities). The weather is cold, the electricity consumption is soaring, and the power supply is in short supply.

2) Electric coal transportation: the pressure of electric coal transportation on roads, railways, aviation and ports such as Daqin Railway and Beijing-Hangzhou Canal has increased; Due to the traffic disruption in the south of the Yangtze River, it is difficult to transport coal from the north to the south, and the coal supply in the south is tight.

3) Transportation: The southern section of the Beijing-Guangzhou line and some sections of the Shanghai-Kunming line were stopped, the trains were delayed many times, and some sections of the Beijing-Zhuhai Expressway were closed, resulting in a large number of passengers stranded on roads and stations.

4) Communication: Several signal communication towers of China Mobile were crushed by continuous heavy snow and freezing rain, which caused some areas to be unable to communicate for a period of time, and the mobile phone had no signal.

5) Commodity supply: some agricultural products in the south are frozen, or cannot be transported to the north in time due to traffic reasons, and food supply in many areas in the north and disaster-stricken areas in the south is short or prices continue to rise.

6) Many electricians and traffic policemen were killed or injured.

(B) the characteristics of low-temperature freezing disasters

1. Wide range

The continuous low temperature, rain, snow and freezing weather affects 20 provinces (autonomous regions and municipalities) such as Guizhou, Hunan, Hubei, Anhui, Jiangxi, Guangxi, Chongqing, Guangdong, Zhejiang, Fujian, Sichuan, Shaanxi, Jiangsu, Yunnan, Gansu, Henan, Qinghai, Tibet, Shanxi and Shanghai.

2. High strength

Since June 65438+1October 10 in 2008, the precipitation in six provinces (regions) in Henan, Sichuan, Shaanxi, Gansu, Qinghai and Ningxia has reached the maximum value in the same period since June 195 1. The lowest temperature in the middle and lower reaches of the Yangtze River dropped to -6 ~ 0℃, and the daily highest temperature was close to the lowest temperature. The average daily temperature in Wuhan and Changsha is close to or lower than 0℃ for more than half a month. The temperature in most parts of Hubei, Anhui, Jiangxi, Hunan and Guizhou is 2 ~ 4℃ lower than normal, and the temperature in central and eastern Hubei, most parts of Hunan and eastern Guizhou is more than 4℃ lower. The average temperatures in Henan, Hubei, Hunan, Guangxi, Guizhou, Gansu and Shaanxi are the lowest in the same period in history, and Jiangxi, Chongqing and Ningxia are the second lowest. The maximum cooling range in most parts of the south of the Yangtze River, south China and northwest China is 10 ~ 20℃, with the temperature in northwest China exceeding 20℃. The snowstorm in Zhejiang is the strongest since 1984, and the snow depth in parts of Anhui and Jiangsu is close to the extreme value of 50 years.

3. Long duration

From 65438+February 2007 1 to 2008 1 October1,the longest continuous days in the middle and lower reaches of the Yangtze River (Jiangsu, Anhui, Hubei, Hunan, Jiangxi, Shanghai) and Guizhou are less than 1954 ~. The number of rainy and snowy days in the middle and lower reaches of the Yangtze River and Guizhou exceeded 1954 ~ 1955, the highest in the same period in history. The number of frozen days is close to 1954 ~ 1955, which is the second largest in the same period in history. Among them, the freezing rain and snow weather in Hunan and Hubei has the longest duration and the most serious impact since 1954.

This disaster has a great influence.

The continuous low temperature, rain, snow and freezing weather has caused great disasters to 20 provinces (autonomous regions and municipalities) such as Hunan, Hubei, Anhui, Jiangxi, Guangxi and Guizhou, especially to transportation, energy supply, power transmission, communication facilities, agricultural production and people's lives. The affected area and direct economic loss of crops have exceeded the losses caused by low temperature rain, snow and freezing disasters in 2007.

(C) the causes of low-temperature freezing disasters

The abnormal atmospheric circulation that caused this low-temperature freezing disaster is mainly manifested in four aspects:

1) Since June 20081,the atmospheric circulation in the middle and high latitudes in Europe and Asia is high in the west and low in the east, which is conducive to the continuous invasion of cold air into China from the northwest along the Hexi Corridor.

2) The south branch trough of the southern margin of the Qinghai-Tibet Plateau is active, which makes warm and humid air continuously transported to China along the Yunnan-Guizhou Plateau.

3) The subtropical high in the northwest Pacific is strong in the north and stable in the southeast of China, so that the main area where cold and warm air meet is located in the middle and lower reaches of the Yangtze River and its south.

4) At the junction of cold and warm air, warm and humid air is forced to rise, forming a stable inversion layer in the middle and lower troposphere, and freezing rain occurs in a large area. This stable combination of abnormal forms of atmospheric circulation has been maintained for more than 20 days, resulting in a rare large-scale continuous low-temperature rain, snow and freezing weather in eastern China.

(D) the government's measures to deal with low-temperature freezing disasters

1) go deep into the front line and command from the front;

2) Strengthen forecasting and early warning, and take precautions beforehand;

3) Strengthen the emergency on duty and do a good job of information submission;

4) Strengthen information release and do a good job in propaganda and guidance;

5) All parties in Qi Xin work together to "protect electricity, traffic and people's livelihood";

6) Strengthen overall planning and prepare emergency materials;

7) Do a good job in post-disaster reconstruction.

(5) Thinking about the low-temperature freezing disaster in South China.

The low temperature and freezing disaster in South China has exposed four weak links in current disaster reduction work:

1) The existing comprehensive monitoring of meteorological disasters can not meet the requirements of meteorological disaster prevention and mitigation in terms of detection range, accuracy, temporal and spatial resolution, etc.

2) The meteorological department underestimated the persistence and intensity of disastrous weather, and the relevant departments did not conduct risk pre-assessment for lifeline projects such as transportation and electric power.

3) Disaster reduction is the behavior of the whole society, and it is necessary to strengthen the cooperation and information sharing of key departments, and to strengthen social emergency linkage and departmental coordination.

4) The channels and means of early warning information release can not meet the needs of the public, the coverage of early warning information is not wide enough, and leading cadres and the public lack disaster prevention awareness and scientific knowledge.