Sudden tornado, please remember these life-saving knowledge!
Reporter Cai Jikang
The tornado disaster in Yancheng, Jiangsu Province on the afternoon of the 13th caused widespread concern. So, how did tornadoes form? Where and when are tornadoes prone to occur? How should the public respond? Xiao Cai, a meteorologist of Zhejiang Voice, interviewed Lou Maoyuan, the chief expert of science popularization of Zhejiang Meteorological Bureau today.
A sudden tornado in Yancheng, Jiangsu Province caused 2 deaths and 15 injuries.
Witnesses: The roofs are flying with them.
At about 4: 15 pm on the 13th, a tornado disaster occurred in some towns in Dafeng District, Yancheng City, Jiangsu Province. According to experts’ appraisal, the tornado is rated as EF2, with medium strength. From the video shot by witnesses on the scene, I saw a huge wind column, like a white dragon, rolling up a huge funnel-shaped vortex and heading straight for the sky. At the crossing point of the tornado, piles of ruins were left, roofs of houses were lifted off and trees were destroyed. The tornado disaster killed 2 people, injured 15 people and damaged 283 farm houses.
What wind is a tornado?
Lou Maoyuan, chief expert of science popularization of the Provincial Meteorological Bureau, said that tornado is a strong destructive convective weather and a small-scale air vortex generated under strong unstable weather conditions.
"Tornadoes are actually produced in thunderstorm clouds. We call them cumulonimbus clouds in meteorology, and the atmospheric environment is often very unstable. Inside this cumulonimbus cloud, there is an updraft and downward flow. When this updraft is stronger than downward flow, it will form a rotating thing, just like when we rub noodles, when one end falls to the ground, it forms a tornado. "
Tornadoes occur and disappear in a short time, often accompanied by strong convective weather systems such as thunderstorms, hail and heavy rain. The central wind power can reach 50-150 m/s, and the diameter is generally between several meters and hundreds of meters. Tornado intensity is divided into six grades: EF0 to EF5. The highest level of EF5 tornado has a wind speed of over 89.4m/s, which can instantly destroy houses and blow cars.
Where do tornadoes "prefer"?
Global tornadoes mainly occur in mid-latitude areas, and tornadoes occur every year in North America, Europe, Russian Federation, China, Japanese and Australian, especially in the United States, which produces an average of 1,141 tornadoes every year. In China, there are more tornadoes in Jiangsu, Guangdong, Hubei, Anhui and other provinces, among which Jiangsu and Guangdong have the most tornadoes, with an average of 4 tornadoes per year. Northern Jiangsu is a high-incidence area of tornadoes because of its low-lying and flat terrain, interwoven rivers and lakes, and the climate transition zone between subtropical zone and warm temperate zone, which is easy to accumulate unstable energy. Spring and summer are tornado-prone seasons in China, with July accounting for the highest proportion. Tornadoes often appear in the afternoon, and tornadoes that occur between 12: 00 and 20: 00 account for 70%.
Lou Maoyuan said: "From our point of view in Zhejiang, the average tornado is less than once a year. Because tornado is a kind of strong convective weather with small scale, sudden and strong destructive power, the forecast of tornado is always a difficult point in weather forecast from a global perspective. "
What can we do in the event of a tornado?
One word: escape!
Lou Maoyuan said that in case of a tornado, we should flee in the opposite direction of the tornado. If it is too late to escape, we can choose the basement or semi-basement to escape.
"Tornado-prone areas, if the weather forecast has a strong thunderstorm tomorrow, then you should pay attention to it, there may be tornadoes, and pay special attention to the sky from the afternoon to the evening of this day. If there is such a tornado in the distance, then the personnel should quickly avoid it from its path in time.
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