What are the characteristics of a typhoon? What are the necessary conditions for formation?

Characteristics of typhoons: low central pressure, air currents converge inward in the horizontal direction and then rise vertically, converging counterclockwise in the northern hemisphere and clockwise in the southern hemisphere.

Typhoon formation must have unique conditions:

First, there must be a vast atmosphere of high temperature and high humidity. The temperature and humidity of the bottom atmosphere in the tropical ocean are mainly determined by the sea surface water temperature, and typhoons can only form on the warm ocean surface where the sea surface temperature is higher than 26 27, and the sea water temperature at a depth of 60 meters is higher than 26 27.

Second, there should be an initial disturbance in which the lower atmosphere converges towards the center and the upper atmosphere spreads outward. Moreover, the high-level divergence must exceed the low-level convergence in order to maintain sufficient updraft, and the low-level disturbance can continue to intensify.

3. The wind speed in the vertical direction should not be too different, and the relative movement of the upper and lower layers of air is very small, so that the latent heat energy released by water vapor condensation in the initial disturbance can be stored in the air column in the eye area of the typhoon, and the warm center structure of the typhoon can be formed and strengthened.

Fourth, it is necessary to have a sufficiently large geostrophic deflection force to act as a typhoon structure.

It is beneficial for the formation of cyclonic vortices. The geostrophic deflection force is close to zero near the equator and increases to the north and south poles, and typhoons basically occur over the ocean about 5 degrees above the equator.

There is no wind in the center, the weather is clear, and the wind is strongest near the center, so the air pressure is the lowest. It is formed in the ocean and carries abundant water vapor, forming conditions: air temperature, 26 or more, area: west coast of the Pacific Ocean. Season: Usually summer (because of high temperatures and low pressure).

The following conditions must be met for the formation of a typhoon: (1) there must be a sufficiently wide tropical ocean surface, and the ocean surface should be 60 meters deep, and the water temperature should generally be exceeded; (2) There are islands in the tropical ocean. Because the temperature on the island is higher than the ocean surface in summer, the hot air on the ground rises, and a depression forms on the surface of the earth; When the air pressure over the ocean around the island is high, the air flows towards the low pressure in the middle of the island.

Due to the geostrophic deflection force, this air flowing towards low pressure forms a tropical vortex rotating counterclockwise in the Northern Hemisphere and a tropical vortex rotating clockwise in the Southern Hemisphere. The development of this vortex leads to the formation of typhoons with winds of 12 or higher. Therefore, typhoons are mostly formed in tropical oceans at latitudes between 5° and 20°.

1. A high temperature and high humidity atmosphere are the primary conditions. Due to the tropical ocean.

The atmospheric temperature and humidity at the bottom are mainly determined by the sea surface water temperature, and typhoons can only form on the warm ocean surface where the sea surface temperature is higher than 27, and even the water temperature at a depth of 60 meters is also required, which is generally higher than 26 27.

Second, in addition to the conditions of high temperature and high temperature, there should be an initial disturbance of the convergence of the lower atmosphere to the center and the diffusion of the upper atmosphere outward. Moreover, the low-level divergence must be lower than the high-level convergence, so that there is sufficient updraft, so that the low-level disturbance can continue to intensify.

3. In order for a typhoon to form, the wind speed in the vertical direction should not be too different, so as to ensure the relative movement of the upper and lower air.

Smaller. Only the relative motion of the upper and lower layers of air is minimal to allow the latent heat released by the condensation of water vapor in the initial disturbance.

It can be stored in the eye of a typhoon.

area of the air column, forming and strengthening the typhoon warm center structure.

Fourth, the geostrophic deflection force.

The effect must be large enough. Because the earth rotates.

It is beneficial for the formation of cyclonic vortices. The geostrophic deflection force gradually increases from the equator to the north and south poles, and is almost zero near the equator, so typhoons do not occur at the equator, and they basically occur on the ocean surface about 5 degrees above the equator.

The three main conditions for the formation of typhoons are: the presence of a sufficiently wide tropical ocean, the presence of a weak tropical vortex, and the need for a sufficiently large deflection force of the Earth's rotation.

1. There is a wide enough tropical ocean.

A sufficiently wide tropical ocean requires not only that the surface temperature of the sea water be higher than that, but that in a layer of water at a depth of 60 meters, the water temperature must exceed this value. The vast ocean surface is a necessary natural environment for the formation of typhoons, because of the friction between the air molecules inside the typhoon, the average daily energy consumption is 3100-4000 calorie centimeters**2, this huge energy is only the latent heat released by the vast tropical ocean.

is possible**. Also, tropical cyclones.

Strong winds swirling around the typhoon can cause the sea water near the center to churn, and in the center of a typhoon where the pressure drops very low, it can even cause the surface of the ocean to rise upwards and then spread out in all directions, so that the sea water churns from the center of the typhoon to the surrounding areas. This churning phenomenon in a typhoon can affect a depth of 60 meters. On the surface of the ocean, where the sea temperature is lower, it is difficult to maintain a typhoon due to the lack of thermal energy.

In order to ensure that the sea surface temperature remains above during this churning process, this warm water layer must be about 60 meters thick.

2. There must be a weak tropical vortex.

Before a typhoon can form, a weak tropical vortex must be present beforehand. We know that the operation of any machine that touches the branch must consume energy, which requires energy**. A typhoon is also a "heat engine, which slowly rotates there at such a huge scale and speed, and consumes a lot of energy, so there must be energy**.

The energy of a typhoon comes from water vapor from tropical oceans. In a pre-existing tropical vortex, the air pressure in the vortex is lower than that in the surrounding area, and the surrounding air carries a large amount of water vapor to the center of the vortex and generates upward movement in the vortex area. Moist air rises, water vapor condenses, and a huge amount of latent heat of condensation is released to make the typhoon a big machine work. Therefore, even with the high temperature and high humidity of the tropical ocean surface water vapor, if there is no strong rise in air to produce condensation and release latent heat process, it is impossible for a typhoon to form a typhoon.

Therefore, the upward movement of the air is an important factor in the formation and maintenance of typhoons. However, its necessary conditions.

It is the presence of a weak tropical vortex.

3. There should be a sufficiently large deflection force for the rotation of the earth.

There should be a sufficiently large geostrophic deflection force for the equator.

is zero, and gradually increases towards the poles, so the typhoon occurs about 5 latitudes away from the equator. As a result of the rotation of the Earth, a force is created that changes the direction of the flow of air, which is called the "Earth's rotation deflection force". On a rotating Earth, the action of the Earth's rotation makes it difficult for the surrounding air to flow directly into the depression.

Rather, it rotates counterclockwise along the center of the depression (in the Northern Hemisphere.

The formation conditions are as follows

The sea surface water temperature is above 26-27°C; The ambient airflow has strong cyclonic and horizontal cut-off resistance. Tropical cyclones (including tropical storms, severe tropical storms and typhoons as defined by the World Meteorological Organization) (including tropical storms, severe tropical storms and typhoons) with sustained winds of metres per second or more at the centre are referred to as typhoons.

After a day of sunlight, a strong cumulonimbus cloud forms on the surface of the sea. The hot air in these cumulonimbus clouds rises, and the cooler air around them is constantly replenished, and it rises again when it is hot, and so on, so that the air above is hot and the air below is cold. The evaporation of water vapor from the hot air above expands the cloud band, which expands to make this movement more violent.

The expanding cloud mass rotates counterclockwise (clockwise in the Southern Hemisphere) under the influence of geostrophic deflection forces, forming a tropical cyclone. The centrifugal force generated by the swirling air in a tropical cyclone throws the air outward, and the air in the center becomes thinner and thinner, and the air pressure decreases, forming a tropical depression - the initial stage of the typhoon.

Because the central pressure of the tropical depression is lower than that of the outside world, the surrounding air rushes to the tropical depression and rises when heated, supplying more energy to the tropical depression than it outputs. At this time, the air rotates more strongly in the tropical depression, the maximum wind force at the center increases, and the pressure at the center decreases further. When the maximum wind force at the center reaches a certain standard, it will be raised to a higher level, that is, the tropical depression will be raised to a tropical storm, and then to a severe tropical storm, a typhoon, and sometimes a strong typhoon or even a super typhoon.

This is mainly determined by the energy input to output ratio, the input energy is greater than the output energy, the typhoon will strengthen, and vice versa.

Typhoons are a highly destructive and harmful weather phenomenon.

There are a few of the 4 conditions for the formation of a typhoon.

From the structure of the typhoon, it can be seen that such a huge behemoth must have unique conditions for its generation:

First, there must be a vast atmosphere of high temperature and high humidity. The temperature and humidity of the bottom atmosphere in the tropical ocean are mainly determined by the sea surface water temperature, and typhoons can only form on the warm ocean surface where the sea surface temperature is higher than 26 27, and the sea water temperature at a depth of 60 meters is higher than 26 27.

Second, there should be an initial disturbance of the lower atmosphere converging to the center and the upper atmosphere spreading outward. Moreover, the high-level divergence must exceed the low-level convergence in order to maintain sufficient updraft, and the low-level disturbance can continue to intensify.

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 is very small, so that the latent heat energy released by water vapor condensation in the initial disturbance can be stored in the air column in the eye area of the typhoon, so as to form and strengthen the warm center structure of the typhoon.

Fourth, there should be a sufficiently large geostrophic deflection force, and the earth's rotation is conducive to the formation of cyclonic vortices. The geostrophic deflection force is close to zero near the equator and increases towards the north and south poles, and typhoons occur over the ocean about 5 degrees above the equator.