How did the typhoon come from and how did it come about? 20

A storm of a special nature that appears near the island of Taiwan is called a typhoon or associated with winds from Taiwan. In the past, it was customary to call tropical cyclones with sea surface temperatures higher than 26 typhoons ** (20 photos) developing on the surface of the tropical ocean as typhoons, and tropical cyclones can be divided into six levels according to their intensity: tropical depression, tropical storm, severe tropical storm, typhoon, strong typhoon and super typhoon.

Since 1989, China has adopted the International Standard for Tropical Cyclone Names and Classifications. According to international practice, China's tropical cyclones occurring in the western North Pacific and the South China Sea are classified according to their central maximum winds: tropical depression with a maximum wind speed of < 8, ( Severe tropical storm (severetropicalstorm), maximum wind speed 10 11, ( Typhoon (ty-phoon), maximum wind speed 12, (

Typhoons originate in tropical seas, where temperatures are high and large amounts of seawater are evaporated into the air, creating a center of low pressure. As the air pressure changes and the earth itself moves, the incoming air also rotates, forming a whirlpool of air that rotates counterclockwise, which is called a tropical cyclone. As long as the temperature does not drop, this tropical cyclone will become more and more powerful, and eventually a typhoon will form.

Preparation points for sakira sliding before the typhoon:

1. Listen, watch or check the typhoon warning information on the Internet in time to understand the best anti-typhoon action countermeasures.

2. Close the doors and windows, and fasten the structures that are easy to be blown by the wind.

3. Move from the dilapidated house to a safe place.

4. People in low-lying areas that may be flooded should be evacuated in time.

5. Check whether the circuit, furnace, gas and other facilities are safe.

6. Kindergartens and schools should take temporary measures to stop and suspend classes if necessary.

A typhoon is a type of tropical storm. Tropical storm is a kind of strong tropical cyclone that occurs on the tropical ocean surface, which is formed by the direct sunlight of the tropical sea, which increases the temperature of the seawater, evaporates the seawater into water vapor, and the colder air around it flows in and replenishes, and then rises, so that the entire airflow continues to expand. The following conditions must be met for a typhoon to occur:

First, there must be a vast atmosphere of high temperature and high humidity; Second, hail should have an initial disturbance of the lower atmosphere converging to the center and spreading outward in the upper layer. Third, the wind speed in the vertical direction should not be too different, and the relative movement of the upper and lower layers of air must be very small; Fourth, there should be a sufficiently large geostrophic deflection force, which is conducive to the formation of cyclonic vortices.

The direction and speed of the typhoon depend on the dynamics acting on the typhoon, and due to the influence of the shape, position, intensity and other factors of the subtropical high, the path of the typhoon is not uniform but becomes diverse. Typhoons are generally accompanied by strong winds and heavy rains, which seriously threaten people's lives and property, and will have a great impact on people's livelihood, agriculture, economy and other departments, and are a serious natural disaster.

China stipulates that the maximum wind force on the ground near the center of the typhoon is 6 7 as a tropical depression; 8 Category 11 is a typhoon; A typhoon of magnitude 12 or higher is considered a strong typhoon. Typhoons hit our country most frequently in July and September.

Because the subtropical high affects the typhoon's movement, it relies on the ambient flow field it provides – strong enough to be in a guiding position. In terms of force, the tropical high provides the horizontal pressure gradient force of the large pressure field.

On the vast sea surface, the main body of a typhoon is mainly affected by three forces: two external forces, namely the geostrophic deflection force and the horizontal pressure gradient force of the large pressure field, and one internal force, that is, the typhoon internal force. The external force is much greater than the internal force.

The movement of a typhoon is mainly guided by the guiding airflow in the environment, such as the airflow at the edge of the subtropical high and the airflow in front of the westerly trough.

The internal force of a typhoon is the force generated by the difference between the north and south of the geostrophic deflection force in the typhoon. Since the geostrophic deflection force in the north of the typhoon is greater than that in the south, this north-south difference will cause the internal force of the typhoon to move in a northwesterly direction.

On the way to the "growth" of the typhoon, there is a "big brother" that has a profound impact on it - the Northwest Pacific Subtropical High (hereinafter referred to as the Subtropical High), which is located in the subtropical high pressure belt and is a warm high pressure system that has broken out. During the Northern Hemisphere summer, it is entrenched over the Pacific Northwest and its powerful "body" controls the flow field around it—on its periphery, the upper-air wind field is usually clockwise.

Most typhoons in the Northwest Pacific originate at the southern edge of the subtropical high and usually move along the periphery of the subtropical high. Taking Typhoon Bavi, which affected the northeast this year, as an example, in the early stage of its land-searching development, the subtropical high stably "circled" the east side of the typhoon, and Bavi moved northeast under the influence of its southwesterly airflow. When the intensity of the typhoon is not as strong as that of the subtropical high, the typhoon is naturally "led by the nose" by the subtropical high.

Typhoons are actually strong tropical cyclones.

A tropical cyclone is a severe weather system that occurs in the tropical oceans and moves forward with the surrounding atmosphere like a vortex in a flowing river. Like extratropical cyclones, the flow in a tropical cyclone in the Northern Hemisphere rotates counterclockwise around the centre and vice versa in the Southern Hemisphere.

The closer you are to the center of the cyclone, the lower the pressure and the stronger the wind. However, the development of a strong tropical cyclone, such as a typhoon, has a calm area of clear skies, known as the eye of the typhoon, at its centre.

Let's put it another way!

When external conditions (such as cooling or automatic condensation of water vapor) cause moisture to condense in air with high humidity, the pressure of the air drops dramatically, creating a negative atmospheric pressure relative to the surrounding space, which is the central negative pressure that forms the typhoon. As soon as this negative pressure is formed, the surrounding air is immediately replenished. Since negative pressure tends to start at low temperatures, it forms a large vortex of air that rotates from the bottom up and around it towards the center – this is the eye of the typhoon!

It's a strong tropical cyclone, look upstairs, it's detailed.