First, the wind
Wind is formed by the horizontal movement of air. There are two ways to move, one is horizontal and the other is vertical. The former forms wind in the troposphere and flows from one place to another, such as monsoon, trade wind and frontal wind. The latter is also formed in the troposphere, but the difference is that the airflow flows from the earth to the air, without the wind we usually feel, and the branches will not move horizontally at this time;
But may be uprooted, just like terrible typhoons, tornadoes and hurricanes. The reason for the formation of wind is very simple, which is caused by the imbalance of hot and cold air. Cold air has a high density and mass, so it sinks and has a high pressure. The density and mass of hot air are small, so it will rise and the pressure is small;
According to the knowledge of physics, in the * * * environment, in order to balance the air pressure, it is necessary to make the air pressure flow at high and low pressure, which leads to the pressure gradient force of air flowing horizontally, perpendicular to the isobaric surface. Because of the circular autobiography of the earth, the earth has tile bias force in both northern and southern hemispheres, and wind is formed under the action of the pressure gradient force and tile bias force.
Second, the types of wind
1, tornado
The air rotates rapidly around the axis of the tornado and is attracted by the extremely low air pressure in the center of the tornado. In the thin layer of air tens of meters thick near the ground, the airflow is sucked into the bottom of the vortex from all directions. Then it becomes a vortex around the axis. The wind in a tornado is always cyclonic, and the air pressure in its center can be 10% lower than that around it. Tornado is a form in which a small part of the huge energy of thunderstorm is released in a small area.
2. Typhoon
Typhoon is a strong storm that occurs in the tropical oceans of the northwest Pacific Ocean and the South China Sea. You must have seen a vortex appear in the river from time to time. In fact, a typhoon is an air vortex, which rotates around its center in the atmosphere and moves forward at the same time. It rotates counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.