Who can sort out the knowledge of typhoon in senior one geography?

Typhoon [Meteorological Terminology]-Source

The source of typhoon is distributed in the vast low latitude ocean surface of the northwest Pacific Ocean. The tropical disturbance in the northwest Pacific intensified and developed to the initial position of typhoon, with a relatively concentrated zone in latitude and longitude. East-west, tropical disturbances developed into typhoons, which were relatively concentrated in four sea areas.

(1) Sea surface in the north-central South China Sea

(2) The sea surface east of the Philippine Islands and near the Ryukyu Islands.

(3) Sea surface near Mariana Islands

(4) Sea surface near Marshall Islands

Typhoon [Meteorological Terminology]-Causes

Typhoon is in the tropical ocean, and the direct sunlight on the sea surface raises the temperature of seawater, which is easy to evaporate into water vapor and spread in the air. Therefore, the air in the tropical ocean has a high temperature and high humidity, and this air expands due to high temperature, resulting in a decrease in density and weight. But the wind near the equator is weak, easy to rise, and there is convection. At the same time, the surrounding cold air flows in to replenish and then rises again. This cycle will eventually make the whole gas column hotter and lighter. However, air flows from high pressure to low pressure just as water flows from high pressure to low pressure. The surrounding high-pressure air will flow to low pressure, forming wind. In summer, due to the direct sunlight moving from the equator to the north, the southeast trade winds in the southern hemisphere cross the equator and become southwest monsoon to invade the northern hemisphere. When they meet the northeast trade wind in the northern hemisphere, the air is forced to rise, thus increasing the convection. Due to the different directions of southwest monsoon and northeast trade wind, when they meet, they often cause fluctuations and vortices. The convergence caused by the southwest monsoon and the northeast trade wind and the continuation of the original convection make the vortex with low pressure continue to deepen, that is, the air around it accelerates to flow to the center of the vortex, and the faster the flow, the greater the wind speed; When the maximum wind speed near the ground reaches or exceeds 32.6 meters per second, we call it a typhoon.

Typhoon [Meteorological Terminology]-Conditions

As can be seen from the typhoon structure, such a huge behemoth must have unique conditions.

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

Second, there should be an initial disturbance that the lower atmosphere converges to the center and the upper atmosphere diffuses outward. Moreover, the divergence of the upper layer must exceed the convergence of the lower layer in order to maintain enough updraft and continuously strengthen the disturbance of the lower layer;

3. The difference of vertical wind speed should not be too big, and the relative motion of the upper and lower air is very small, so that the latent heat released by water vapor condensation in the initial disturbance can be stored in the air column in the typhoon eye area, forming and strengthening the typhoon warm center structure;

Fourth, there must be enough geostrophic deflection, 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 at the north and south poles. The typhoon occurred on the ocean surface about 5 latitudes from the equator.

Typhoon [Meteorological Terminology]-Origin

Typhoon "Weipa" published Wang Cunzhong's article "The Origin of Typhoon Terminology and Its Naming Principles" in Volume 8, Issue 2, 2006. This paper discusses the historical evolution of the word "typhoon". The author thinks that in ancient times, typhoons were called hurricanes, and the name "Mao Feng" (1956, simplified as typhoon) didn't begin to be used until the late Ming and early Qing dynasties, and the meaning of hurricanes became a general term for cold wave gale or non-typhoon gale.

There are two theories about the origin of typhoon. The first category is "tone sandhi theory", which includes three types: one is the evolution from Cantonese "gale"; Second, it evolved from the "wind screen" in Minnan dialect; Third, during the Dutch occupation of Taiwan Province Province, it was named after Typhoon Taifeng, a character in the Greek theocracy epic. The second category is "origin theory", that is, naming a typhoon according to its origin.

Typhoon [Meteorological Terminology]-Classification

Typhoon SuperTY: The maximum average wind speed near the bottom center is ≥ 5 1.0m/s, that is, 16 or more.

Strong typhoon (STY): The maximum average wind speed near the bottom center is 4 1.5-50.9 m/s, which is 14- 15.

Typhoon (TY): the maximum average wind speed near the center of the ground floor is 32.7-4 1.4m/s, which is 12- 13.

Severe tropical storm (STS): the maximum average wind speed near the bottom center is 24.5-32.6m/s, that is, wind10-1.

Tropical storm (TS): the maximum average wind speed near the bottom center 17.2-24.4m/s, that is, the wind force is 8-9.

Tropical depression (TD): the maximum average wind speed near the bottom center 10.8- 17. 1 m/s, that is, the wind force is 6-7.

Typhoon [Meteorological Terminology]-Classification

Typhoon China National Meteorological Bureau stipulated that the international tropical cyclone name and grade standard should be used from 1 month 1989.

According to international standards, the maximum average wind force near the center of tropical cyclone is less than 8, which is called tropical depression, 8 ~ 9 is called tropical storm,10 ~1is called strong tropical storm, and1is called typhoon. In order to issue typhoon warnings in a unified way, typhoons appearing in the west of150 E and north of the equator are numbered according to the order of occurrence every year. For example, Typhoon 9202 means that this typhoon is the second typhoon west of 1992. Typhoon activity is seasonal. The typhoons that affect China mainly occur from May to 10, especially from July to September.

The source of typhoon is regional. Typhoon sources are distributed on the ocean surface with islands near 5 north latitude and 20 south latitude. Typhoons affecting China are mainly formed in the western Pacific Ocean east of the Philippines, near Guam and in the middle of the South China Sea.

Typhoon [Meteorological Terminology]-Path

The direction and speed of typhoon movement in the typhoon path depend on the force acting on the typhoon. Power is divided into internal force and external force. The internal force is the resultant force from north to west caused by the different geostrophic skewness caused by the latitude difference between north and south within the typhoon range. The larger the typhoon range, the stronger the wind speed and the greater the internal force. The external force is the force of the external environment flow field on the typhoon vortex, that is, the guiding force of the easterly belt of the basic airflow on the south side of the subtropical high in the northern hemisphere. Internal force mainly plays a role in the initial generation of typhoon, while external force is the leading force to manipulate the movement of typhoon, so typhoon basically moves from east to west. Due to the influence of the shape, position and intensity of subtropical high, the typhoon's moving path is not uniform and becomes diverse. Taking the typhoon moving path in the northwest Pacific as an example, there are three moving paths:

(1) The westward typhoon moved from the east of the Philippines to the west, crossed the South China Sea, and finally landed on Hainan Island in China or northern Vietnam. This route mostly occurs in 10- 1 1, and 2006 is a typical example.

(2) Landing type: The typhoon moved to the northwest, crossed the Taiwan Province Strait, landed in the coastal areas of Guangdong, Fujian and Zhejiang, and gradually weakened into a low pressure. This typhoon has the greatest impact on China. The two typhoons "90 15" and "97 1 1" which have had the greatest impact on Jiangsu in recent years belong to this type, and basically follow this path from July to August.

(3) Parabolic type: the typhoon moves to the northwest first, then turns to the northeast without landing when approaching the eastern coast of China, and turns to the vicinity of Japan. The path is parabolic, mostly occurring in May-June and 9-165438+1October.

After the typhoon is formed, it will generally move out of the source and experience the evolution process of development, weakening and extinction. A mature typhoon has a circular vortex radius of 500 km ~ 1000 km and a height of 15 km ~ 20 km. Typhoon consists of three parts: peripheral area, maximum wind speed area and typhoon eye. The wind speed in the peripheral area increases from outside to inside, with spiral clouds and precipitation; The strongest precipitation occurs in the maximum wind speed area, with an average width of 8 km ~ 19 km, and there is a circular cloud wall between it and the typhoon eye; The typhoon eye is located in the center of the typhoon. The most common typhoon eye is round or oval, ranging in diameter from 10 km to 70 km, with an average of about 45km. The weather in typhoon eye is calm, partly cloudy, dry and warm.

After the typhoon is formed, it will move.

The moving path basically moves from east to west along the outer edge of subtropical high. However, influenced by many factors, the moving path is very complicated. Taking the typhoon movement path in the western North Pacific as an example, the path is divided into three:

① Move to the west. The typhoon moved westward from the eastern Philippines, crossed the South China Sea and landed in Hainan Island or Vietnam.

② Northwest path. The typhoon moved from the east of the Philippines to the northwest, crossed the Ryukyu Islands and landed in Jiangsu, Zhejiang and Fujian provinces.

③ Turning path. The typhoon moved from the east of the Philippines to the northwest, then turned to the northeast, and its path was parabolic.

Typhoon [Meteorological Terminology]-Structure

A typhoon is a mature typhoon. According to its structure and weather, it is divided into three parts: typhoon eye, vortex storm area and peripheral gale area, which are arranged concentrically from the center to the outside. The typhoon eye is located in the center of the typhoon, with a diameter of about 5 ~ 10 km.

Downward flow prevails at the eye of the typhoon, so the weather is clear and windless. Outside the eye of the typhoon is a vortex wind and rain area, where strong convergent updraft prevails, forming thick clouds, and violent storms occur from time to time. The wind force is often above 12, which is the worst weather area for typhoons.

Further outward is the peripheral windy area, and the wind speed decreases outward, and the wind force is generally above 6. Typhoon crossing often brings stormy weather, causing huge waves on the sea surface and seriously threatening navigation safety. After landing, it can destroy crops and various building facilities. It has caused great losses to people's lives and property and is a disastrous weather with great harm.

At the lower level, typhoons mainly flow into low-pressure inflow. Because of the angular momentum balance, the inner region can produce strong wind speed, and the outflow airflow of anticyclone is in the upper layer. Strong upward movement connects the upper and lower circulation, which is the main feature of typhoon circulation.

The hottest temperature in a typhoon is caused by the sinking movement, which occurs at the inner edge of the eye wall, where there is the strongest sinking movement. Convergence is strongest at the maximum wind speed radius in the lower layer of typhoon, and the maximum wind speed radius does not change much with height, which is located in the eye wall. In addition, the asymmetry of typhoon structure is also a feature that people pay attention to this year. The analysis shows that there is obvious asymmetry in the inner and outer areas of the typhoon, which plays an important role in the development of the typhoon and the transportation of momentum and kinetic energy. Weather-scale typhoon is a powerful dynamic energy source in the atmosphere, so it should have an important impact on the change and maintenance of atmospheric circulation in terms of energy, which has attracted people's attention. On the issue of energy, it was also pointed out this year that the horizontal vortex transport of angular momentum is very important outside typhoons; In addition, the generation and transport of momentum in the outer region is also very important, which should not be ignored in the typhoon energy budget. These are all related to the asymmetry of the typhoon.

Typhoon [Meteorological Terminology]-Characteristics

Typhoon According to the relevant data of typhoon occurrence in recent years, the laws and characteristics of typhoon occurrence mainly have the following points: First, seasonality. Typhoons (including tropical storms) usually occur between summer and autumn, with the earliest in early May and the latest in 1 1 month. Second, it is difficult to accurately predict the landing position of the typhoon center. The wind direction of typhoon changes from time to time, which is often unexpected, and the landing position of typhoon center is often different from the forecast. Third, the typhoon is rotating. When landing, the wind direction is generally north first and then south. Fourth, the damage is serious. It is very destructive to unstable buildings, overhead lines, trees, ships at sea, cage fish farming and coastal crops. Fifth, strong typhoons are often accompanied by heavy rains, tides and tsunamis. Sixth, when a strong typhoon occurs, manpower is irresistible and it is easy to cause casualties.

China numbered the tropical depressions that entered the west of l50 degrees east longitude and the north of l0 degrees north latitude, and the maximum wind force near the center was 8, according to the sequence of occurrence every year. This is the "Typhoon X this year (tropical storm, strong tropical storm)" that we heard or saw on radio and television.

Typhoon [Meteorological Terminology]-Countermeasures

What should residents pay attention to when the typhoon comes?

1, be alert to typhoon trends, pay attention to listening to and watching media reports, or learn about the latest situation of typhoons through meteorological consultation telephones and meteorological websites.

2. When the typhoon comes, close the doors and windows to prevent it from raining, and remove the flowerpots on the windowsill or balcony to prevent them from falling.

When the typhoon comes, it is easy for some large billboards to fall, trees to be blown down and telephone poles to fall to the ground. It's best to avoid going out when the typhoon comes.

People who have to go out to work must choose a safe zone when avoiding the wind and rain, and be careful to "fly" to cause trouble. In the wild, we should pay attention to the dangers such as road collapse and broken trees.

5. Typhoon weather will cause water accumulation on the road surface and ground sliding, which will affect driving or cars and cause accidents. Therefore, drivers must slow down when driving, and friends who ride bicycles had better choose to walk or take the bus in bad weather.

Typhoon [meteorological terminology]-pros and cons

Typhoon Typhoon not only brings serious disasters such as storms to the landing area, but also has certain benefits.

In Southeast Asian countries, including China and the United States, typhoon rainfall accounts for more than 1/4 of the total rainfall in these areas, so if there is no typhoon, the agricultural difficulties in these countries will be unimaginable; In addition, typhoons play an important role in regulating the earth's heat and maintaining the heat balance. As we all know, tropical areas receive the most solar radiation heat, so the climate is also the hottest, while cold areas are just the opposite. Due to the activity of typhoon, the heat in tropical areas is dispersed to high latitudes, which compensates the heat in cold areas. If there is no typhoon, the climate in tropical areas will get hotter and hotter, while in cold areas it will get colder and colder, and the temperate zone on the natural earth will no longer exist, and many animals and plants will become extinct because it is difficult to adapt. This will be a very terrible scene.

profit

First, with the rapid growth of global population and the development of industry and agriculture, the demand for fresh water is expanding day by day, and the limited fresh water resources on land are unevenly distributed, so the problem of water shortage in the world is becoming more and more serious. However, tropical storms and typhoons have brought people abundant fresh water. Typhoon brings a lot of rainfall to the coast of China, the coast of the Sea of Japan, India, Southeast Asia and the southeastern United States, accounting for more than 1/4 of the total precipitation in these areas, which is of great significance to improving the fresh water supply and ecological environment in these areas.

Secondly, the tropical and subtropical areas near the equator have the longest sunshine time, and the dry heat is unbearable. If there is no typhoon to dissipate heat in these areas, it will be hotter there and the surface sand shortage will be more serious. At the same time, the cold zone will be colder and the temperate zone will disappear. China will not have a spring city like Kunming, nor will it have an evergreen Guangzhou, and "Beidacang" and Inner Mongolia grassland will also cease to exist.

Third, the maximum speed of a typhoon can reach more than 200 kilometers per hour, and its energy is equivalent to the energy released when 400 2000-ton hydrogen bombs explode. Wherever they go, they destroy everything. This huge energy can directly cause disasters to mankind, but it also keeps the earth in thermal balance and makes mankind live and work in peace and contentment.

Fourthly, in the process of typhoon formation and operation with huge energy, with the help of lightning, long chains of water molecules can be interrupted to form active short-chain water molecules. Living things on the earth can increase the vitality of life after inhaling these short-chain water molecules, thus making the earth's ecology continue to develop.

Fifth, typhoons can also increase fishing output. Every time a typhoon blows, it turns over the river, rolling up the nutrients in the river bottom and the sea, increasing the bait, attracting fish to gather near the water surface, and naturally increasing the catch.

disaster

Typhoon is a very destructive and disastrous weather system, but sometimes it can also play a beneficial role in eliminating drought. Its harmfulness mainly includes three aspects:

(1) Strong wind. The maximum wind force near the typhoon center is generally above 8.

② Heavy rain. Typhoon is one of the strongest rainstorm weather systems. Generally, it can produce rainfall of150 mm ~ 1 000 mm in the area where typhoons pass, and a few typhoons can produce heavy rain above1000 mm. The torrential rain caused by Typhoon No.3 in the upper reaches of Huaihe River 1975 created the extreme value of heavy rain in Chinese mainland and caused the "75.8" flood in Henan.

③ Storm surge. Generally, typhoons will increase water in coastal waters, and the maximum water increase in coastal areas of Jiangsu Province can reach 3m. Typhoon "9608" and "97 1 1" increased water, which made Jiangsu's coastal areas along the Yangtze River have a super-historical climax.

Typhoon [Meteorological Terminology]-Prevention and Control

Strengthening the monitoring and forecasting of typhoons is an important measure to reduce typhoon disasters. Meteorological satellites are mainly used to detect typhoons. The existence and size of the typhoon can be clearly seen on the satellite cloud picture. Using meteorological satellite data, we can determine the location of typhoon center, estimate the intensity of typhoon, monitor the direction and speed of typhoon movement, and the area where severe storms occur, which plays a key role in preventing and mitigating typhoon disasters. When the typhoon reaches the offshore, the radar can also detect it. There are also forecasters of meteorological stations, who, based on all kinds of information obtained, analyze the trend of typhoons, the place and time of landing, issue typhoon forecasts, typhoon emergency reports or emergency warnings in time, serve the public through television, radio and other media, and provide decision-making basis for governments at all levels. Issuing typhoon forecast or emergency report is an important measure to reduce typhoon disaster.

Typhoon [Meteorological Terminology]-Monitoring and Forecasting

Observing the severity and frequency of disasters caused by typhoons has attracted worldwide attention. Marine meteorological scientists from all over the world have been committed to monitoring and forecasting typhoons for a long time. The earliest modern typhoon forecast can be traced back to1the beginning of the 8th century. As soon as the weather map was born, the typhoon forecast began. At present, weather chart method is still one of the main methods to forecast typhoons.

Typhoons occur in tropical waters, so it is difficult to monitor. Except for some typhoon data observed by observation stations located in a few tropical islands, most of them were obtained by voluntary observation by merchant ships of various countries sailing on the world ocean routes. The routes of these merchant ships are relatively fixed, and there are even fewer routes in typhoon areas. At the same time, before the typhoon comes, merchant ships sailing near the typhoon will avoid it in advance to avoid the typhoon attack, thus losing an excellent opportunity to obtain typhoon data. 1930, the us military sent a coast guard ship to the typhoon area for actual measurement, but it was difficult to avoid the bad luck brought by the typhoon disaster, and eventually it ended in a shipwreck. 1943 On July 27th, the United States began to successfully observe typhoons by plane for the first time, and made formal typhoon observation in the Pacific Ocean from 1945, which has continued to this day and achieved great success.

At present, using the cloud images obtained by meteorological satellites to analyze the location and moving path of typhoons has achieved practical results. However, in the early and late stages of typhoon development, due to the weakening and disappearance of typhoon eye, it is often difficult to closely monitor the movement of typhoon from the cloud image, which brings certain difficulties to accurately predict typhoon. Therefore, it is still an optimal method to make up for the deficiency of cloud images by using aircraft observation data, so aircraft observation of typhoons has its unique role.

When an airplane observes a typhoon, it usually drops to a height of 3,000 meters (equivalent to 700 hectopascals) when approaching the eye of the typhoon, and radiosondes are successively put in 50 kilometers away from the eye of the typhoon to carry out three-dimensional observation. This operation is repeated three times. Choosing this altitude to fly is the most favorable for observing typhoons, and it is also a safer altitude to fly over the typhoon eye. Because the height of 3000 meters is the top of the typhoon inflow layer, the convection at this height is relatively smaller than that at the lower level. However, for typhoons that developed in the early stage or weakened in the later stage, it is more appropriate for the plane to descend to a height of 300 meters because the typhoon eye is not obvious.

Typhoon forecasting in China is the responsibility of the National Meteorological Center in Beijing, and the forecasting service network is established by meteorological stations and ocean stations at all levels in coastal provinces, cities and counties across the country. After analyzing and processing the actual data obtained from ground monitoring network, high-altitude meteorological observation network, meteorological radar observation network, meteorological satellite monitoring system, ocean monitoring network and international meteorological data exchange system, they issued typhoon forecasts and warnings.