Compare the main characteristics, hazards and defensive measures of typhoon and cold wave.

Typhoon and hurricane are both a kind of wind, but they happen in different places and have different names. The typhoon is in the western part of the North Pacific Ocean, west of the international date, including the South China Sea; Tropical cyclones in the Atlantic Ocean or the eastern North Pacific Ocean are called hurricanes, which means hurricanes in the United States and typhoons in the Philippines, China and Japan.

Typhoon is a strong tropical cyclone generated on the surface of tropical ocean. Typhoons are often accompanied by strong winds and heavy rains. The wind rotates counterclockwise. Isobars and isotherms are approximately a set of concentric circles. The central air pressure is the lowest and the temperature is the highest.

Typhoon classification

Typhoons are classified according to the maximum wind force near the center of tropical cyclones. In the past, the meteorological department of our country called the winds with the magnitude of 8 to 1 1 as typhoons, and the winds with the magnitude of 12 or above as strong typhoons. From 65438+65438+ 1 in 0989 to 65438+1in October, it is called a tropical storm when the maximum wind force near the center is 8 ~ 9, and it is called a strong tropical storm when10 ~1. In 2006, according to the notice of National Standard for Tropical Cyclone Grades (GBT 1920 1-2006) issued by China Meteorological Bureau, tropical cyclones were divided into six grades according to the maximum surface wind speed near the center: when the maximum wind force near the center is 16 or above, it is called super typhoon, and the maximum wind force near the center is/KLOC-. The maximum wind force near the center 12- 13 is called typhoon, l0- 1 1 is called strong tropical storm, 8-9 is called tropical storm, and 12- 13 is called tropical storm. For the sake of simplicity, the following is still collectively referred to as typhoon.

typhoon track

Typhoon paths can be roughly divided into three categories: ① Westward typhoons move from the east to the west of the Philippines, cross the South China Sea, and finally land on Hainan Island in China or northern Vietnam. (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. (3) Parabolic type: The typhoon moves to the northwest first, then turns to the northeast when approaching the eastern coast of China, and turns to the vicinity of Japan, with a parabolic path. Typhoon 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.

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 5 OOKM ~ 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.

Number of typhoons

China numbered the tropical depressions that entered the west of l50 degrees east longitude and the north of l0 degrees north latitude. The winds near the center were strong and reached magnitude 8, which were arranged in the order of annual occurrence. This is the "Typhoon X this year (tropical storm, strong tropical storm)" that we heard or saw on radio and television.

The number of typhoons is also the number of tropical cyclones. People want to number tropical cyclones, on the one hand, because a tropical cyclone often lasts for more than a week, and several tropical cyclones may appear in the ocean at the same time. With the serial number, there will be no confusion; On the other hand, the naming, definition, classification method and determination of the center position of tropical cyclones are different in different countries and methods, even in the same country, they are not exactly the same among different meteorological stations, which often leads to various misunderstandings and confusion in use.

Starting from 1959, China began to number tropical cyclones (tropical storms and above) that occur or enter the Pacific Ocean and the South China Sea north of the equator and west of the 180 meridian every year in order of occurrence. Offshore tropical cyclone. In the case of clear cloud structure and circulation, as long as the maximum average wind force near the center is above 7, it is also numbered. The serial number consists of four digits. The first two digits indicate the year. The last two digits are the serial numbers of tropical cyclones above storm level in that year. For example, last year's typhoon Du Fu (13) numbered O3 13. , indicating the tropical cyclone with storm level 13 or above that occurred in 2003. Tropical depression and tropical disturbance are not numbered.

Typhoon naming

At the beginning of the 20th century, people began to name typhoons. It is said that the first person to name a typhoon was an Australian forecaster in the early 20th century. He named tropical cyclones as political figures he didn't like, so that meteorologists could call them publicly. In the northwest Pacific, the official naming of typhoons began with 1945. At first, only female names were used. Later, it is said that due to the opposition of feminists, starting from 1979, men's names and women's names were used alternately. Until 1997, 1 65438+1October 25th to 65438+February1,the 30th meeting of the Typhoon Committee of the World Meteorological Organization (WMO) held in Hong Kong decided that tropical cyclones in the northwest Pacific Ocean and the South China Sea should be named in Asian style, and it was decided that tropical cyclones in the year of 2000 should be named in the Asian style. The new naming method is to make a naming table in advance and then reuse it year after year in sequence. The naming table * * * has 140 names and is provided by 14 member countries and regions in the Asia-Pacific region to which WMO belongs, such as Cambodia, China, North Korea, Hong Kong, Japan, Laos, Macau, Malaysia, Micronesia, the Philippines, South Korea, Thailand, the United States and Vietnam. Each country or region provides 65,438+00 names. The 140 names are divided into 10 groups, and each group has 14 names. Arranged in alphabetical order according to the English names of member countries, and recycled in turn. At the same time, the original number of tropical cyclones remains.

Browse the typhoon naming table. Names are rarely used, mostly animals, plants, food and so on. There are also some names that are adjectives or beautiful legends, such as Yutu and Wukong. The name "Rhododendron" was provided by China, which is the familiar Rhododendron: "Korowang" that landed in China a while ago was provided by Cambodia, which is the name of a tree: "Morak" was provided by Thailand, which means jade; "Ibudu" is a name provided by the Philippines, which means chimney or water pipe to discharge rainwater from the roof into the ditch.

Under normal circumstances, the pre-established named list is recycled year after year in sequence, but under special circumstances, the named list will also be adjusted. For example, when a typhoon is notorious for causing particularly serious disasters or casualties and becomes a well-known typhoon, in order to prevent it from having the same name as other typhoons, the name will be deleted from the current naming list and replaced with a new name. The following is the typhoon nomenclature table put into use on June 65438+1 October1day, 2006:

Typhoon name (implemented from June 65438+1 October1)

Remarks in Column 1, Column 2, Column 3, Column 4 and Column 5

English/Chinese name source

David Kong-Rey Kony Nakri Nakri Krovan Sarica Salika Cambodian

China Wang lung Wang lung yutu yutu fengshen rhododendron hippocampus

Kirogi Hongyan Toraji Zhi Tao Kalmaegi Seagull Mujigae Rainbow Meari Marsh North Korea

Kai Tak Kai Tak Manyi Iman Phoenix Caiyun Ma Caiyun-Saddle China Hongkong

Tambin Libra Bunny Bunny North Crown Kopp Dajue Tokage Tokage

BOL aven Blavin Pabuk pabu hanfone Bau ng Kesana Nock-loto Lao

Pearl Butterfly Wasp Palma Palma Plum Blossom China Macau

Jelawat Sepat Saint Nuri Parrot Melor Jasmine Merbok Miaobai Malaysia

Unia El Yun Ni said that she would get married soon.

Bilis bilis danas danas hagupit hagupit lupit talas talas Philippines

Kaemi Megnari Lily Changmi Rose Mirinae Galaxy Noru Olu North Korea

Thai rose

Maria Maria Francisco Van Gogh Higos Omais Omes Rocklock USA

Samay Samay Lekima Lichima Bavi Hong Kong Letter Business Kang Sen Sanka Viet Nam

Shana, Cambodia

Wukong Wukong Haiyan Poseidon Temple Wood Dian Mu Haitang Haitang China

Song Qing Bodur Liu Yang Bunule Xia Hong Mindur Dandelion Nargai Niger North Korea

Shanshan Lingling Lingling Dolphin White Dolphin Lion Mountain Lion Mountain Banyan China Hongkong

Yagi Capricorn Kaji Sailfish Whale Seiyuu Whale Compass Washi Skyhawk Japan

Xiangshan Elephant God Fa Sai Fa Qian Chan Hong Chan Hongnan Village Nanchuan Masa Mai Sha Laos

Jasper Jasper Pipa Lotus Malou Agate Coral China Macau

Moranti Moranti Marval Mawa

Micronesia, Chao Gu

A small village in Manila, the capital of the Philippines.

Lv Huiyi swan catfish Nabi butterfly

Durian durian Ramasun Mora camorra Keba Siam Kanukanu Thailand

You can go to the center of America to have a look.

Trami Tan Mei Xialong Xia Bo Vamco Ring Gaosongda Sanda Sura Viet Nam

Advantages and disadvantages of typhoon

In addition to bringing serious disasters such as storms to the landing areas, typhoons also have certain benefits. Judging from the typhoon structure, such a 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 spreads 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; Third, the vertical wind speed cannot be too different, and the relative motion between 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. According to statistics, the typhoon rainfall in Southeast Asian countries, including China and the United States, accounts for more than 1/4 of the total rainfall in these areas, so without typhoons, the agricultural difficulties in these countries would 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.

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cold wave

Strong cold air in the north broke out in the south, and there was severe cooling and windy weather in the path. When the temperature drops to a certain standard, it is called a cold wave. China Meteorological Bureau defines a cold wave as: within 24 hours, the average temperature drops by more than 10℃, and the lowest temperature reaches below 5℃. China has a vast territory and complex terrain, and the climate varies greatly from place to place. Therefore, local meteorological stations can also formulate cold wave standards in their own regions according to local climate characteristics.

The main reason for the cold wave weather is that in the Arctic, due to the weak sunlight, the ground and the atmosphere get less heat, and it snows all the year round. In winter, the direct sunlight passes through the equator and reaches the southern hemisphere. The arctic region is colder and wider, and the temperature is generally below MINUS 40℃-50℃. Large-scale cold air masses gather to a certain extent, and under the action of suitable high-altitude circulation, they will invade southward on a large scale, forming cold wave weather.

Cold wave and strong cold air usually bring strong winds and cool weather, which is the main disastrous weather in winter half a year in China. Cold waves and strong winds are a great threat to coastal areas, such as the cold wave on April 2 1 ~ 25, 1969. Strong winds hit the Bohai Sea, the Yellow Sea and Hebei, Shandong, Henan and other provinces, with land winds of 7 ~ 8 and offshore winds of 8 ~ 10. At this time, the astronomical tide was just right, and the outbreak of cold wave caused the rare storm surge in Bohai Bay and Laizhou Bay for decades. On the northern shore of Shandong Province, the sea water rose by more than 3 meters, washed away the seawall by more than 50 kilometers, and the sea water flowed backwards for 30 ~ 40 kilometers.

The outbreak of cold wave has different characteristics in different geographical environments. In the northwest desert and loess plateau, it is characterized by less wind and snow, which is easy to cause sandstorm weather. In Inner Mongolia grassland, it is windy, snowy and cold. In North China and Huanghuai areas, cold waves are often accompanied by snow and snow. In the northeast, it shows more violent winds and heavy snow, and the snowfall is the highest in the country. Jiangnan is often accompanied by freezing rain.

The freezing rain, snow and ice weather brought by the cold wave is extremely harmful to transportation. For example, 1987 1 1 A cold wave process in the last ten days caused the turnouts of several stations under the jurisdiction of Harbin, Shenyang, Beijing and Urumqi to freeze, the tracks were buried by snow, the communication signals failed, and the train operation was blocked. After the rain and snow, the roads were frozen and skidded, and traffic accidents increased obviously. Cold wave is very harmful to human health. The windy and cool weather can easily lead to colds, tracheitis, coronary heart disease, cor pulmonale, stroke, asthma, myocardial infarction, angina pectoris, migraine and other diseases, and sometimes make patients worse.

Cold wave is a kind of disastrous weather, which brings great harm to society. Once the meteorological station issued a cold wave warning, people should pay attention.