The monsoon climate in China is remarkable, so in what ways is it remarkable? (This question is valid for two days)

China has a vast territory, the northwest is located in the hinterland of Eurasia, the largest continent in the world, the southeast is close to the largest surface Pacific Ocean, and the southwest is the highest plateau in the world, the Qinghai-Tibet Plateau. This extremely complicated geographical condition makes China's climate have strong monsoon, continental and type diversity characteristics. Compared with other countries in the same latitude in the world, this feature of China's climate is very unique. The monsoon climate is obvious. China is located in the southeast of Eurasia. Facing the vast ocean, the huge thermal difference between land and sea makes the characteristics of monsoon climate in China more obvious. The main performance is that the prevailing wind direction changes significantly in winter and summer, and with the advance and retreat of monsoon, the precipitation also changes obviously seasonally. In winter, Chinese mainland is mainly controlled by polar continental air mass or denatured polar continental air mass. At the altitude of 80 ~ 90 E, most of them are high-pressure ridges, while the coastal altitude is often large troughs. The cold air behind the front ridge goes south continuously, which strengthens the cold high pressure on the ground (Mongolian high pressure), and the warm ocean is mostly controlled by low pressure. The airflow constantly flows from the high pressure area to the low pressure area, which makes the northwest wind, north wind and northeast wind prevail in the lower troposphere in winter in China. The polar continental cold high and its accompanying polar front or sub-cold front are the main weather control system in winter in China, and the weather and climate are characterized by less precipitation, low temperature and dryness. In particular, the cold wave or strong cold air weather process lasts for a long time and has a wide range of influence, and the accompanying strong wind and cooling are harmful to industrial and agricultural production.

In summer, most parts of Chinese mainland are controlled by tropical and subtropical marine air masses and tropical continental air masses. The altitude is a trough of low pressure at 70 ~ 80 east longitude, and the coastal area is a shallow ridge. The ground pressure system is occupied by the Mongolian low pressure in Eurasia, which cooperates with the high pressure in the ocean, making southwest wind, south wind and southeast wind prevail in the lower troposphere in summer in China. At this time, in addition to the polar cold air and its accompanying cold front, continental thermal depression, subtropical high, tropical depression, tropical cyclone and easterly wave have become the main systems affecting the weather in China. Weather and climate are characterized by high temperature, high humidity and rainy weather. This climatic feature of rain and heat in the same season provides good conditions for agricultural production in China. The combination of high temperature and abundant rainfall makes China a major rice producing area in the world. Rice planting in China can be as far north as Mohe River in Heilongjiang Province, which benefits from the climate characteristics of the same season of rain and heat. However, continuous heavy rain or local heavy rainfall in summer in China often causes large-scale or local serious floods. The violent storms carried by tropical cyclones have a great impact on fishery production and maritime traffic, even causing loss of life and property, and often cause windstorms and floods near landing sites (sometimes deep inland). The arrival of summer monsoon is marked by the sudden increase of rainfall. Generally speaking, the summer monsoon rain belt appears in the northern part of the South China Sea in early May and moves to the coast of South China in mid-May. Then slowly push north and stop in South China in late May. It suddenly pushed northward in early June and reached the middle and lower reaches of the Yangtze River in mid-June, which was the beginning of the Meiyu period. Meiyu usually lasts until the beginning of July. Then, the summer monsoon affects the area north of Huaihe River. In late July, North China and Northeast China entered the peak of the annual rainy season, which lasted until early August. Since the middle and late August, the summer monsoon rain belt has rapidly withdrawn southward, and the rainfall in the whole country (except the areas affected by tropical cyclones in the southeast coast) has rapidly decreased. From mid-September of 10 to early October of 10, it stagnated in the central and eastern parts of Jianghuai, forming a relatively rainy belt. Due to the influence of topography, there are many autumn rains in West China, and it is also a rainy area. 65438+ 10 September, the weather in North China and Central China is mostly crisp in autumn. 5438+ 10 In the middle of June, the rain belt retreated to South China. Whether the rainy season starts and retreats normally in all parts of China is closely related to the advance and retreat time of the summer monsoon. The interannual differences such as the arrival, retreat and maintenance time of summer monsoon determine the different summer precipitation conditions and the distribution of drought and flood areas in China. Statistics show that in the year with strong summer monsoon, the rain belt moves rapidly to the north, and it is rainy in the north. The rainy period in the middle and lower reaches of the Yangtze River is short, and the summer drought is serious. On the contrary, the rain belt in the middle and lower reaches of the Yangtze River is stagnant, with excessive rainfall and flooding, while drought occurs in the north, such as 1999. Therefore, the characteristics of monsoon climate, especially the abnormal changes of winter and summer monsoon, make China one of the countries with the most frequent meteorological disasters in the world. Drought, rainstorm, flood and chilling injury are the main meteorological disasters in China. According to the statistics of 1950 ~ 1999, the average area affected by drought, wind and hail, low temperature frost and other disasters in China is about 38 million hectares every year.

According to the classification of heat index, the climate type of China is located in the southeast of Eurasia, the world's largest land, facing the world's largest ocean Pacific Ocean, with complex terrain and vast territory. From Altun Mountain in the west to Wusuli River in the east, it spans 63 longitudes. It starts from Mohe River in the north and reaches Zengmu shoal in the South China Sea in the south, with a latitude difference of 49 degrees between north and south. Therefore, the climate in China is very complicated and diverse. In terms of heat, China spans equatorial belt, tropics, subtropics, temperate zones, mountains, plateaus and cold climate from south to north. 87% of the country's land area is temperate, subtropical and tropical. According to the classification of heat index, China has the following climate types: (1) equatorial monsoon climate. Located in the South China Sea Island area south of north latitude1o. The annual average temperature is above 26℃, the annual accumulated temperature reaches 9000℃, the temperature changes little, and the rainfall distribution in the four seasons is relatively uniform. (2) Tropical monsoon climate. Including southern Taiwan Province Province, Leizhou Peninsula and Hainan Island. The annual accumulated temperature is ≥8000℃, the average temperature in Leng Yue is not lower than 16℃, the annual extreme minimum temperature is not lower than 5℃ on average for many years, and the extreme minimum temperature is generally not lower than 0℃, and there is no frost all year round. (3) Tropical monsoon climate. North China and South China belong to this type of climate. The annual accumulated temperature is between 4500℃ and 8000℃, and the average temperature in Leng Yue is between -8℃ and 0℃, which is a transitional zone between subtropical zone and temperate zone. The temperature is quite high in summer (the average temperature is ≥25℃ for at least 6 periods, that is, 30 days) and quite low in winter. (4) temperate monsoon climate. Inner Mongolia and northern Xinjiang in China belong to this type of climate. The annual accumulated temperature is lower than 1600 ~ 3400℃, the average temperature in Leng Yue is -28 ~-8℃, and the average temperature in summer is still above 22℃, but rarely exceeds 25℃. (5) Cold temperate monsoon climate. The northeastern part of China belongs to this climate type. The annual accumulated temperature is lower than 1600℃, and the average temperature in Leng Yue is lower than -28℃. The cold degree in winter is worse than that in temperate zone, and the cold period is longer than that in temperate zone. (6) Plateau climate. The Qinghai-Tibet Plateau in China belongs to this type of climate. The annual accumulated temperature is lower than 2000℃, the daily average temperature is lower than 10℃, and the hottest temperature is also lower than 5℃ or even lower than 0℃. The daily temperature difference is large and the annual range is small, but the solar radiation is strong and the sunshine is sufficient. The continental climate is very strong. The characteristics of Chinese mainland's sexual climate are mainly manifested in "the annual and daily changes of temperature are great; Winter is cold, and the temperature difference between north and south is large; The weather is hot in summer, and the temperature in the whole country is generally high. Leng Yue occurs most frequently: in June 5438+10, the average temperature in Leng Yue is much lower than the world average at the same latitude. The annual average minimum temperature in the northernmost part of China is below -45℃, while it reaches 1 1℃ in Hainan Island, with a difference of more than 50℃. In summer, China is the hottest country in the same latitude in the world except desert and arid areas. Almost all the hottest months occur in July, and the average monthly temperature in the south of Huaihe River in eastern China is basically between 28℃ and 30℃. However, due to the strong continental climate in China, the north-south difference of the average temperature in the hottest month is much smaller than that in Leng Yue. Throughout the year, the national temperature basically rises with the increase of latitude. Most of Heilongjiang Province, Junggar Basin and Turpan Basin in Xinjiang have annual variation above 40℃, and the highest is close to 50℃. The Yellow River basin is about 30℃; The middle and lower reaches of the Yangtze River are about 20℃; The Pearl River Basin is about 15℃. The daily range of average temperature is the same as that of annual range, and the farther inland to the northwest, the greater the daily range. Generally, it is less than 10℃ in the south of Huaihe River and Qinling Mountain. As far north as the North China Plain, it will increase to 10 ~ 12℃, the Loess Plateau and most parts of Northeast China will reach 12 ~ 14℃, and Meng Xin and Tibet will reach 14 ~ 16℃ or above. According to the classification of water regime, China's climate features are humid, semi-humid, semi-arid and arid areas from southeast to northeast, of which the area of arid and semi-arid areas accounts for about half of the national area. Generally speaking, the whole country can be divided into three regions: the eastern monsoon region, the northwest arid region and the Qinghai-Tibet alpine region. Due to the different latitudes and distances from the ocean, as well as the complex terrain, the climate types in China are various. Northeast China is mainly a humid and semi-humid temperate climate zone. Winter is cold and long, and summer is short. Cold damage and drought are the biggest unfavorable factors for agricultural production in this area. Most of North China is a semi-humid warm temperate climate zone, and some are semi-arid warm temperate climate zones. It is cold and rainy in winter; It is hot and rainy in summer, with heavy rain and severe spring drought. Spring drought and unstable precipitation in summer are the restrictive factors of agricultural production in this area. The Yangtze River basin and the south of the Yangtze River are humid subtropical climate zones. It is wet and cold in winter, rainy in early summer, high temperature and drought in midsummer, and tropical cyclones along the coast in summer and autumn, which are the main climatic characteristics of this area. Most of South China and parts of Southwest China also have humid subtropical climate. It is mild in winter and rainy from late spring to summer. However, the lack of rain and drought in winter and spring affects the utilization of heat; The influence of rainstorm, flood and tropical cyclone also restricts the economic development of this area to varying degrees. The tropical humid climate is distributed in Leizhou Peninsula, Hainan Island and South China Sea Islands. In the south of Taiwan Province Province and Yunnan Province, it is warm and hot all year round, with a lot of precipitation and obvious wet and dry conditions. There is less rain in winter and spring, and heavy rain and tropical cyclone activities are more frequent in summer. Inner Mongolia belongs to semi-arid climate zone. Northwest China is mainly an arid climate zone, and agriculture is limited to oases and hilly areas. The shortage of water resources is the main factor restricting the sustainable economic development in this area. But this area is rich in wind and solar energy resources. Most parts of the Qinghai-Tibet Plateau are cold and rainy. The climate in different regions is very different, from cold zone to tropical zone. The above are only the main climatic characteristics of several regions. As for mountain climate, its types are more complex and diverse. Even in a mountainous area, the scale is different. Three-dimensional climate characteristics at different levels provide favorable climate resources for mountain development.