What are the hazards of the cold wave?

Harm and benefit of cold wave 1. The harm of freezing injury to crops (the biggest harm is in autumn and spring, when seedlings unearthed in spring are greatly cooled, they will freeze to death, and when crops are immature in autumn, they will cool down, which will reduce crop production)-strong cooling.

2. Blow down ships and destroy buildings and farms-gale

3. Press power lines and power poles-heavy snow and freezing rain.

Cold wave and strong cold air usually bring strong winds and cool weather, which is the main disastrous weather in winter half a year in China. For example, during the cold wave from April 26th, 65438 to April 25th, 969, strong winds hit Bohai Sea, Yellow Sea, Hebei, Shandong, Henan and other provinces, with land winds of 7-8 and offshore winds of 8- 10. At this time, it was the astronomical tide, and the outbreak of cold wave caused the rare storm surge in Bohai Bay and Laizhou Bay for decades. On the northern shore of Shandong Province, the sea water rose by more than 3 meters, washed away the seawall by more than 50 kilometers, and the sea water flowed backwards for 30 ~ 40 kilometers.

The freezing rain, snow and ice weather brought by the cold wave is extremely harmful to transportation. It will cause the switch of the railway station to freeze, the track will be buried by snow, the communication signal will be interrupted and the train operation will be blocked. After the rain and snow, the roads were frozen and skidded, and traffic accidents increased obviously.

Cold wave is very harmful to human health. The windy and cool weather can easily lead to colds, tracheitis, coronary heart disease, cor pulmonale, stroke, asthma, myocardial infarction, angina pectoris, migraine and other diseases, and sometimes make patients worse.

Few people mention that the cold wave also has beneficial effects. The research and analysis of geographers show that the cold wave contributes to the heat exchange on the earth's surface. With the increase of latitude, the energy received by the earth from solar radiation gradually weakened, so the earth formed tropical, temperate and cold zones. The cold wave injects a lot of cold air into tropical areas, which makes large-scale heat exchange on the ground, which is very helpful to maintain the ecological balance of nature and maintain the lush species.

Meteorologists believe that the cold wave is the guarantee of good weather. China is affected by monsoon, and the winter climate is dry, which is a dry season. However, whenever the cold wave invades the south, it will often bring a wide range of rain and snow weather, alleviate the winter drought and benefit crops. Why can the agricultural proverb "Xue Ruizhao has a good year" be circulated among the people for generations? This is because snow water has a high nitrogen content, which is more than five times that of ordinary water, and can greatly increase the nitrogen in the soil. Snow water can also accelerate the decomposition of soil organic matter, thus increasing the organic fertilizer in the soil. The heavy snow covered the overwintering crops and played the role of a quilt, keeping out the cold and keeping warm.

There is a saying that "winter is not cold, and the coming year is not abundant", which also has its scientific truth. Experts in crop pest control believe that the low temperature brought by the cold wave is the most effective natural "insecticide" at present, which can kill a large number of pests and germs lurking in the soil for the winter, or inhibit their reproduction and reduce pests and diseases in the coming year. According to the survey data of agricultural technology stations around the country, pesticides can be saved by more than 60% in the year of heavy snow and winter closure.

Cold waves can also bring wind resources. Scientists believe that wind is a valuable energy source without pollution. The power generation efficiency of the world-famous Miyakojima wind power station during the cold wave is 1.5 times that of the usual one.