What does strange rain have to do with tornadoes?

There is an ancient book in China called Sou Shen Ji, written by Gan Bao, a Jin Dynasty man. This book collects all kinds of magical ghost stories that have been circulated among the people and recorded in some historical books since the Han Dynasty. It has always been regarded as China's earliest mystery novel in the literary world.

The book records:

In August, the second year of Emperor Yong Guang of the Han and Yuan Dynasties (42 BC), many intertwined firewood fell from the sky.

In the autumn of the fourth year of Emperor Gaozu Hongjia (BC 17), in today's Jixian County, Hebei Province, a large number of fish fell from the sky.

In July of the third year of Emperor Huan of the Han Dynasty (AD 149), a lot of mutton fell from the sky in Nianbo County, Gansu Province.

Ok, just list the above three. You must think these records are nonsense. Seriously, for years, people really don't know what happened.

Some ancient literati with serious feudal superstitions used these strange phenomena to promote superstition. What did you say?/Sorry? This is an act of god, an act of god, or a sign of world chaos.

Although some people of insight don't believe in these superstitions, they can't explain why.

Turning to the history books of our country, this strange rain phenomenon has been recorded in almost every dynasty. In addition to the three mentioned above, there are falling grains, falling dust, falling copper coins, falling millet and so on. It's amazing.

Abroad, there is a similar situation. /kloc-in the summer of 0/940, a small village in Gorky province of the Soviet Union, Misia, was accompanied by torrential rain, and a large number of shiny silver coins fell from the sky. The Russian words on the silver coin indicate that this is the silver coin of Russian Tsar Ivan V of Russia.

Modern science tells us that these strange rainfall records in history are by no means lies fabricated by people, and most of them are historical facts. The source of this strange rain is a tornado with strong winds in nature.

A tornado is a small but powerful cyclone. It often forms a fast rotating airflow with indomitable spirit, the bottom is connected with the ground or the ocean, and the top is connected with the dark clouds, moving along a certain route. The air pressure in the center of a tornado is very low and the wind speed is very high, so things on the ground or water from rivers, lakes and seas can often be sucked into the sky. In the area where the tornado passed, houses were opened, the soil on the ground was swept away, and crops were blown into the air; If it happens at sea, it will suck a lot of seawater into the cyclone and move to far, far places with it.

1940 The "Silver Coin Rain" in Gorky Province of the Soviet Union was caused by a tornado passing through a nearby place where a Russian nobleman buried silver coins, and the topsoil there was swept into the air together with the silver coins and fell with the heavy rain.

Tornadoes are extremely destructive. 1March, 925 18, a tornado occurred in the United States, killing 889 people and injuring 1980 people, which caused great damage to the local economy. 1On September 24th, 956, a tornado occurred in Pudong, China, which unexpectedly lifted an oil tank with a weight of 220,000 Jin and a height of three or four floors into the air and threw it to120m away.

The destructive power of a tornado is related to its huge wind speed. Sometimes, the wind speed of tornadoes can reach more than 100 meters per second, while the wind speed of 12 gale is only 33 meters per second.

Tornadoes are caused by strong air disturbances. During the summer rainstorm, the temperature difference between the ground temperature and the upper air temperature can reach 50-60 degrees. In this way, the hot air rises rapidly and the cold air drops rapidly, which is easy to form a rotating airflow and eventually form a powerful tornado.

In China, tornadoes may occur in almost every province and city, but the scope of tornadoes is not large, usually within the diameter of 1.5 km. Moving a few kilometers or dozens of kilometers is enough, sometimes it can exceed 100 kilometers, but generally speaking, the influence range is limited. Recently, many meteorologists from all over the world are engaged in the study of tornadoes and attach great importance to the forecast of tornadoes. They have tried to monitor the occurrence and development of tornadoes with radar and meteorological satellites, and can give an alarm half an hour before the tornado occurs. People can take preventive measures in advance to reduce the losses caused by tornadoes.