An example of sandstorm

On May 5th, 2065438+0/kloc-0, Pujiang, Chengdu was suspected to encounter a sandstorm: hundreds of kilograms of steel plates mixed with foam boards hung in mid-air and kept spinning ... 10 seconds later, the cyclone disappeared, and all the colored steel plates fell and scattered all over the floor, and the mid-air was still gray. Compared with tornado, the power of sandstorm is obviously weakened, which is characterized by rolling up the dust on the ground to form a rotating dust column. A thrilling scene happened in Group 7 of Wangdian Village, Daxing Town, Pujiang: the color steel roof of a villager's house was overturned, and hundreds of kilograms of steel plates were hung in the air mixed with foam boards and kept spinning ... 10 seconds later, the wind force of this cyclone was decreasing, but it had moved forward for several kilometers. Colored steel plates suspended in the air were scattered on the ground, causing no casualties. Wind power and destructive power are less than tornadoes.

100 kg steel plate is twisted and deformed outside 100 m.

The incident happened near the highway, and Liu Dequan and his family were cleaning up the colored steel plates on the roof scattered in the open space. His rabbit farm is a big bungalow, and now there are only a few walls left, and most of the colored steel plates on the roof have been blown to the ground. The reporter saw that many steel plates were scattered on the roadside of the house, and the foam board sandwiched between the steel plates was torn into several pieces. /kloc-I saw a twisted steel plate in the grass more than 0/00 meters away. "This kind of steel plate weighs a hundred kilograms, and it is difficult for two people to lift it." Liu Dequan said that when he saw the steel plates in front of him, he couldn't believe it was windy. He said that he had lived here for more than 30 years and had never seen such a strong wind. He suspected that it was a tornado in the movie.

Or the dust wind has limited influence on tornadoes.

A whirlwind suddenly appeared in the flat and open village. Is this really a tornado? "If it is really a tornado, it will be more powerful and the scope of influence will not be just a few houses." What happened to Liu Deyi's family was a "dusty wind". This is also a kind of rotating wind, but it is obviously weaker than a tornado and has limited influence. It is characterized by rolling up the dust on the ground to form a rotating dust column. Generally, within a certain range, two winds with equal intensity meet to produce strong wind shear and vortex. For example, the east wind and the south wind blow together, and the two are "entangled" and quickly rotate and rise in a short time. The formation of dust wind is related to the strong warming of the ground, and whether it can be formed has a great relationship with the ground topography. Common in high-rise buildings and places with uneven heating.

At about 3 pm on August 27th, 2004, a' black column' wind swept the whole construction site (National Swimming Center) in mid-air, with a height of seven or eight meters and a thickness of three or four meters. The whirlwind rolled up the yellow sand and even the iron sheet on the wall of the construction site, and the iron sheet was rolled up to more than ten meters. We quickly hid in the dormitory of the construction site, but our house collapsed in the wind. "Chen is still concerned about the experience of being injured on the afternoon of 27th. However, experts disagree on whether this "troublesome" wind is a sandstorm or a tornado. Meteorologists at the Beijing Meteorological Observatory said that the local cyclone that lasted for about 20 minutes on the 27th rolled up and destroyed three temporary facilities at the site of the National Swimming Center, injuring more than 40 people, two of whom were seriously injured. This sudden cyclone should be a strong sandstorm, not a tornado, and tornado are two different kinds of disaster weather, and their influence scope and power are much smaller than tornadoes. Under normal circumstances, sandstorms will not cause major natural disasters, but sometimes very strong sandstorms can still bring small disasters. Sandstorm is a normal disastrous weather, and its height is generally five to six stories high. Once it happens, people can see it with the naked eye. Because of its small scope of influence, if citizens find it, they should look for tall and solid buildings to escape in time.

However, meteorologist Ms. Zhou has different definitions of "sandstorm". She believes that sandstorms usually occur in sunny and dry weather. When the ground surface is unevenly heated, a small cyclone is generated in the near-surface gas layer, which can lift dust and some small objects into the air and form a small dust column. A common afternoon whirlwind in summer belongs to dusty wind. Ms. Zhou said that through TV video observation, the cyclone state in Wali Township, Chaoyang, Beijing on the afternoon of the 27th was close to a tornado, and the local strong convective weather under the conditions of thunderstorms and strong winds was the main reason for the formation of this cyclone. Of course, the terrain also has a certain relationship. The narrow space between buildings will accelerate the rotation of the wind and may also increase the strong convective weather. The meteorological department is organizing experts to analyze whether this "accident-causing" cyclone is a sandstorm or a tornado according to relevant data.

The "suspected" tornado is actually a "dust wind"

Experts say that this kind of wind has weak destructive power, and there is no record of sandstorm yesterday in Beijing's meteorological history. Meteorologists have analyzed that sandstorms and tornadoes are two different kinds of disastrous weather. The scope and power of sandstorms are much smaller than tornadoes, and there is no record of sandstorms in Beijing's meteorological history. Meteorologists say that sandstorm is a normal disastrous weather, which refers to a small cyclone generated in the near-surface atmosphere. It can lift dust and some small objects into the air to form a dust column. On the afternoon of August 27th, 2004, the strong convective weather in Beijing was the main culprit of sandstorm. "Yesterday, under the influence of strong convective weather, the ground was unevenly heated and the wind shear was very rapid, causing the air to vortex." According to meteorologists, the height of sandstorms is generally five to six stories high. Once it happens, people can see it with the naked eye. Because its impact is very small, citizens should avoid it in time if they find it. Sandstorm, like the earth, is very common on Mars. It is a kind of rotating convection movement caused by uneven cold and heat on the ground. It is characterized by rolling up ground dust and forming a rotating dust column with light and small objects.

As early as 20 12, NASA's Mars Reconnaissance Orbiter once photographed a top-down sandstorm, when the highest sandstorm reached 12 miles (20 kilometers).