Real-time release system of typhoon path (all these statements about typhoon are misunderstandings)

Typhoon Candu reached 17 at its strongest, far stronger than the last fireworks. Moreover, its moving path is constantly changing. The initial direction of "Candu" was Fujian and Guangdong, and later it went straight to Jiangsu, Zhejiang and Shanghai. When the typhoon was near the island of Taiwan Province Province, the intensity did not decrease obviously, and the super typhoon level remained above 100 hours.

As one of the most serious meteorological disasters, strong winds, huge waves, trees falling and houses falling off, and typhoons with large volume and high energy are often accompanied by powerful destructive power from the sea to the mainland. A powerful typhoon can not only "attack at close range"-bring strong storms to the places it passes, but also "attack at a long distance"-bring persistent rainstorms to areas beyond a certain distance, and "kill cattle across the mountain".

Moreover, after the typhoon landed, it does not mean that its influence is over. Although the wind speed and intensity will be weakened by ground friction, the heavy rainfall brought by typhoon and its secondary disasters may still bring great losses to inland areas, and the prevention work cannot be relaxed at all. Shanghai rumor platform summarizes several windproof misunderstandings. Please be vigilant and always do a good job of safety protection.

Myth 1: Autumn typhoon is not as powerful as summer typhoon.

In fact, autumn typhoons are more prone to "tough guys". Usually, typhoons generated in June-August are called "summer typhoons", and typhoons generated in September-165438+1October are called "autumn typhoons". According to the statistics of China Weather Network, in the past 72 years, the number of typhoons generated in summer is 833, which is the most active season, and the number of typhoons generated in autumn is 82 1 typhoon, which is second only to summer. Autumn is the most active in September, with the national average landing number reaching 1.72, second only to August and July, when typhoons are most frequent.

Shao Peng, a meteorologist from China Weather Network, said that the path of autumn typhoon is changeable and it is difficult to predict, which is mainly related to the weather system that affects autumn typhoon. In autumn, the weather systems such as westerly belt, subtropical high and cold air compete with each other, regardless of the outcome, so it becomes alternating between east, west, north and south, which improves the difficulty of forecasting. Compared with summer typhoons, the landing sites of autumn typhoons in China are obviously southward, mostly concentrated in South China. This is mainly related to the position change of subtropical high. Typhoons generally move along the periphery of subtropical high. After entering September, the subtropical high gradually moved eastward and southward, and the typhoon was suppressed by the subtropical high and its path was southward.

Although the number of landings is less than that of typhoons in summer, typhoons in autumn are more prone to "malicious roles". According to the statistics of China Weather Network, during the period of 1949-2020, super typhoon accounts for 27.9% of the typhoons generated in autumn, much higher than 18% in summer. The destructive power of typhoon in autumn is great because the direct point of the sun moved from the equator to the tropic of cancer from the vernal equinox, which heated the tropical ocean in the northern hemisphere and the heat of seawater accumulated continuously. Usually, the sea surface temperature is the highest from August to September, and the high sea surface temperature is beneficial to typhoon generation and energy enhancement. At the same time, from the end of August to the beginning of September, cold air began to be active, which increased the pressure gradient and the wind speed near the typhoon center, which was also conducive to the enhancement of typhoon intensity. In addition, due to the gradual increase of cold air in autumn, typhoons are more likely to encounter cold air, and the combination of the two will often lead to heavy precipitation, leading to greater disasters.

Myth 2: The impact will end after the typhoon lands.

In fact, after the typhoon goes deep into the land, it will still bring wind and rain effects. Although the intensity of the typhoon will gradually weaken after landing, it still carries rich warm and humid air. Once it interacts with the cold air over the land, it may cause heavy rain, heavy rain and even heavy rain, as well as strong convective weather such as thunderstorms and local tornadoes. The typhoon that goes deep into the land will lead to the suspension of trains, subways and flights, affecting the normal operation of the city; In rural areas, strong winds and heavy rains cause crop lodging, diseases and insect pests, and even epidemics and ecological environment destruction.

△ The picture of "Rainstorm Causes Trees to Lodge" uploaded by netizens.

When a typhoon strikes, it is extremely dangerous to go outdoors, and most of the victims are in the process of going out. For example, someone looking for shelter outdoors was hit by a billboard blown by a typhoon and died unfortunately; Others overturned due to strong winds during driving and were unfortunately injured; Farmers worried about farmland damage, went out to check, and were involved in the skyrocketing river on the way, and were unfortunately killed; Someone tried to repair the roof because of water leakage, but because of the strong wind, he couldn't keep his balance and fell off the eaves, which killed him.

△ Video of "Passers-by being smashed by billboards" uploaded by netizens.

If handled in the wrong way, it may lead to tragedy. Therefore, when the typhoon comes, please be sure to stay indoors and avoid going out, especially to avoid playing in dangerous mountainous areas. When you have to go out, be careful of falling objects, and pay attention to fences, street trees, billboards and other falling objects on both sides of the road. Don't relax after the gale. There will be branches, glass and other sundries on the road, and there will be many puddles. When walking, avoid obstacles. When driving, you should pay attention to avoid stagnant water sections and low-lying areas.

Myth 3: It is safe to remove the typhoon warning signal.

In fact, we can't underestimate the derivative disaster. As the intensity of the typhoon weakens after landing, the typhoon warning signal will also be lifted, but this does not mean that the typhoon has died, and its residual forces may still have a serious impact. It is necessary to focus on preventing flash floods, mudslides, landslides, urban and rural waterlogging and meteorological disasters caused by heavy rainfall, as well as derivative disasters such as small and medium-sized river reservoirs, ponds and dams. Even if the typhoon warning signal has been lifted, we should pay attention to the rainstorm warning signal, flash flood warning signal and geological disaster warning signal. People who have moved out of the typhoon-affected areas need to wait until the early warning signal is completely lifted before returning.

Source: Shanghai rumor platform editor: