Why is the northern Jiangsu region vulnerable to tornadoes?
Suqian and Yancheng in Jiangsu were hit by tornadoes on September 19th.
According to the Emergency Management Bureau of Suqian City, at around 17:20 on the same day, an EF2 tornado occurred in Daxing Town, Suyu District, and Nancai Township, Economic Development Zone, Suqian City. A total of 5 people died, 4 were seriously injured, 5512 people were affected, 137 houses collapsed, 41.8 hectares of crops were damaged, and 405 people were temporarily relocated.
According to the official platform "Funing Release" of the Funing County Party Committee and Government in Yancheng City, at 20:30, an EF3 tornado occurred in Lupu and Banhu towns in Funing County, causing 5 serious injuries and 4 minor injuries despite rescue efforts. According to preliminary statistics, 1364 people were affected by the disaster in the two towns, 614 houses were damaged, more than 1800 trees were fallen, 199 hectares of crops were damaged, and 129 people were relocated and resettled.
On the 20th, the reporter learned from relevant departments in Suqian City that the social order in the disaster area has returned to normal. Insurance companies have rushed to the scene to inspect and settle claims, and other post disaster disposal work is fully underway. The relevant departments of Funing County told Pengpai News that the roads in the disaster stricken area have been cleared, tents, quilts and other materials have been distributed in place, and the affected people have been properly resettled.
The bedroom roof was lifted off
At 17:25 on the 19th, Li Lei, the owner of an automobile trade shop in Nancai Township, Suqian Economic Development Zone, received a call from his father while taking his eldest daughter out of school: "There was an accident at home, and there was a strong wind. The baby's face was scratched by glass." Li Lei returned home and found that the tempered glass door on the first floor was completely shattered, the metal rolling shutter door disappeared, and pots, pans, and children's toys were scattered on the first floor. The roof of the three bedrooms on the second floor was lifted off, opening a large "skylight".
Li Lei's mother said that when the tornado passed through, the sky was dark and there were constant sounds of collisions. Li Lei's youngest son is sleeping in the bedroom on the second floor. She quickly ran to the bedroom and hugged the child in her arms. As soon as he got up, the glass was crushed by the wind. The 3-year-old doll's face and scalp were punctured with a lot of broken glass, and his head was also scratched by broken bricks and glass. Fortunately, it was all skin injuries.
The South Street of Nancai Township is about 500 meters long, with many two-story buildings on both sides. The first floor is a commercial shop, and the second floor is inhabited by people. The first floor of Li Lei's house is a storefront, where cars and accessories are placed, while his family lives on the second floor. The day before the tornado, Li Lei moved the new car parked on the first floor.
According to the news released by the Emergency Management Bureau of Suqian City on the noon of the 20th, after emergency repairs, all power supply in the affected areas has been restored and road traffic has been restored to normal.
Meteorological experts in Jiangsu Province stated in a media interview that due to the impact of the Jianghuai cyclone, a large-scale heavy rainfall and strong winds began in Jiangsu from northwest to southeast on the afternoon of the 19th. Experts say that it is usually not easy for tornadoes to occur in Jiangsu in mid to late September, but recently, due to high temperatures and the influence of the Jianghuai cyclone, strong dynamic conditions have led to rare tornado events.
Why are tornadoes prone to occur in the northern Jiangsu region
A tornado is a strong, small-scale air vortex that is extremely difficult to predict. According to the Chinese meteorological industry standard "Tornado Intensity Level", tornado intensity is divided into four levels based on the maximum value of near surface gust wind speed at the time of occurrence. The first level corresponds to EF0 and below, the second level corresponds to EF1, the third level corresponds to EF2 and EF3, and the fourth level corresponds to EF4 and EF5.
Jiangsu is a region with a high incidence of tornadoes in China. The article "Spatial and temporal distribution characteristics and circulation classification of tornadoes in northern Jiangsu" published in "Agricultural Disaster Research" in 2021 pointed out that by analyzing the spatial and temporal distribution, level distribution, weather background characteristics, and storm morphology characteristics of tornadoes in Jiangsu from 2006 to 2018, it was found that tornadoes in Jiangsu are mainly distributed along the eastern coast, along the central Yangtze River, and in the western part of Huaibei.
From the perspective of occurrence time, Jiangsu tornadoes are mainly concentrated in spring and summer. The number of occurrences in July and August accounts for about 90% of the whole year, and about 78% occur from 15:00 to 20:00. Yancheng, located on the eastern coast, is the city with the highest incidence of tornadoes in Jiangsu, followed by Xuzhou.
In terms of intensity, since the 21st century, Jiangsu has not recorded an EF5 level extreme tornado event, but there has been an EF4 level tornado, also known as the "6.23" Funing strong tornado. According to the official website of the Yancheng Municipal Government, on the afternoon of June 23, 2016, some areas of Funing and Sheyang in Yancheng were hit by tornadoes and hail, resulting in 99 deaths and 846 injuries.
Why do tornadoes occur frequently in northern Jiangsu? The article "Spatial and Temporal Distribution and Storm Morphology Characteristics of Jiangsu Tornadoes" published in the 2021 issue of the "Meteorology" magazine pointed out that the terrain in northern Jiangsu is relatively low-lying and flat. Compared to areas with uneven terrain, the friction force generated by the northern Jiangsu plain on the airflow is small, making it easy to form tornadoes. In addition, the water network in northern Jiangsu is dense, adjacent to rivers and seas, and located in the transitional zone between subtropical and warm temperate zones, which easily accumulates unstable energy, providing thermal and dynamic conditions for the formation of tornadoes.
