Why are there only typhoons and few thunderstorms in coastal cities?

In China's coastal areas, typhoons hit us more or less every summer and autumn, causing great loss of life and property. As a kind of disastrous weather, it can be said that when it comes to typhoon, no one will show a good impression on it. However, everything has duality. Typhoon has brought disaster to human beings, but if there is no typhoon, human beings will be more miserable. Scientific research has found that typhoons have at least the following benefits for human beings:

First of all, typhoons bring people abundant fresh water. Typhoon brought a lot of rainfall to the coast of China, the coast of the Sea of Japan, India, Southeast Asia and the southeastern United States.

Secondly, the tropical and subtropical areas near the equator have the longest sunshine time, and the dry heat is unbearable. If there is no typhoon to dissipate heat in these areas, it will be hotter there and the surface sand shortage will be more serious. At the same time, the cold zone will be colder and the temperate zone will disappear. China will not have a spring city like Kunming, nor will it have an evergreen Guangzhou, and "Beidacang" and Inner Mongolia grassland will also cease to exist.

Third, the typhoon can reach a top speed of more than 200 kilometers per hour, and it is invincible wherever it goes. This huge energy can directly cause disasters to mankind, but it also keeps the earth in thermal balance and makes mankind live and work in peace and contentment.

Fourth, typhoons can also increase fishing output. Every time a typhoon blows, it turns over the river, rolling up the nutrients in the river bottom and the sea, increasing the bait, attracting fish to gather near the water surface, and naturally increasing the catch.

According to statistics, the typhoon rainfall in Southeast Asian countries including China and the United States accounts for more than 1/4 of the total rainfall in these areas, so if there is no typhoon, the agricultural difficulties in these countries are unimaginable; In addition, typhoons play an important role in regulating the earth's heat and maintaining the heat balance. As we all know, tropical areas receive the most solar radiation heat, so the climate is also the hottest, while cold areas are just the opposite. Due to the activity of typhoon, the heat in tropical areas is dispersed to high latitudes, which compensates the heat in cold areas. If there is no typhoon, the climate in tropical areas will get hotter and hotter, while the climate in cold areas will get colder and colder, and the temperate zone on the natural earth will no longer exist, and many plants and animals will probably become extinct because it is difficult to adapt.

According to the report of the World Meteorological Organization, the number of people who die from tropical storms in the world is about 2,000 to 3,000 each year. The average annual economic loss caused by typhoons in countries along the western Pacific Ocean is about $4 billion. China is also a country with severe typhoon disasters.

disaster

Typhoon is a disastrous weather system with strong destructive power, and its harmfulness mainly includes three aspects:

(1) Strong wind. The maximum wind force near the center of tropical cyclone reaching typhoon level is above 12.

② Heavy rain. Typhoon is one of the weather systems that bring heavy rain. It may produce rainfall of 150 ~ 300mm in the area it passes through, and a few typhoons can directly or indirectly produce rainstorm above 1000mm, such as the rainstorm in southern Henan after tropical cyclone No.3 +0975 landed, which broke the rainfall records in some areas (Henan 75.8 incident).

③ Storm surge. Generally, typhoons will increase the water in coastal waters, and the maximum water increase in Jiangsu Province can reach 3 meters. Typhoon "9608" and "97 1 1" increased water, which made Jiangsu's coastal areas along the Yangtze River have a super-historical climax.

Typhoon often brings stormy weather when crossing the border, causing huge waves on the sea surface, which seriously threatens the safety of navigation. After the typhoon landed, the storm surge may destroy crops and various building facilities, causing great losses to people's lives and property. [ 12]?

In addition, typhoon is one of the potential risk factors for diabetes, hypertension, cardiovascular diseases, respiratory diseases, infectious diseases and other diseases. The collapse of houses, glass fragments, collision of floating objects and falling from high altitude caused by typhoon will all lead to various injuries, which has the characteristics of high disability rate and high mortality rate. Gong Zhenyu's research on the current situation of Typhoon Yunna in 2004 shows that the occurrence of injuries is closely related to wind speed and rainfall. Among the direct casualties caused by typhoon, the fatality rate of hard object injury is the highest, reaching 3 1%, and the collision injury is 19%. [ 14]?

After the typhoon, the destruction of public health services and health care infrastructure, pollution of clean water, changes in population density (especially crowded tents), population migration, increased environmental exposure due to damaged houses and changes in the ecological environment have all increased the possibility of infectious diseases. Typhoon is a serious natural disaster, which will not only cause serious casualties and economic losses, but also bring serious psychological effects and mental injuries such as anxiety, depression and post-traumatic stress disorder to the victims. Such as post-traumatic stress disorder (PTSD), PTSD is the most important influence of tropical cyclones on human psychology and mental health.