Who can help me find the climate in Guangzhou?

Guangzhou is located at 23.6% north latitude, not in the tropics, living by the sea, about100km away from the sea. The land is flat and vast, so there are few boils. There is no heat in summer, no frost and snow in winter, the four seasons are unknown, the trees are evergreen all the year round, flowers bloom at four seasons, and the fields are often harvested. There are only cold and warm changes in the middle of the year, and most disasters are losses caused by drought and flood. Therefore, the climate in Guangzhou is characterized by hot and humid. It is hot in midsummer, but many showers (that is, white rain) can make grass grow early. After three winters, you can go back to the south to beg for rain. Therefore, there is a proverb "Sweat in winter rain". It is foggy in autumn and winter morning, rainy in spring and summer, not hot in dog days, and it turns cloudy and cold. Therefore, all local chronicles say: "It's summer all the time, and when it rains, it becomes autumn". They also said, "It's better to worry than to take medicine.". According to today's climate observation records, the correct description of the above ancient climate can still be confirmed.

Guangzhou is located in the tropics, so the sunshine is strong. Every summer, the sun shines overhead twice (no one is seen at noon), that is, in early June and mid-July. However, in winter, the minimum sun is above 45, so the radiation is still very large, and residents can go north, which is what the ancient book said. Therefore, there is only a cool season in Guangzhou, and there is no cold season, that is, the total direct solar radiation reaches 59 kcal /cm ~ 2 in the whole year, with sunny days in autumn being the most, so "autumn tiger" has become synonymous with traditional hot weather. However, it is not hot in July and August because the plain is cheerful, the sea breeze is regulated, the water network is dense, the water vapor absorbs more heat when evaporating, and there are many clouds and thunderstorms. The average temperature does not exceed 28.2℃, which is one degree lower than that of Shaoguan in mountainous areas and 29.2℃ higher than that of China stoves. Geographically, the area between the Tropic of Cancer is tropical. The temperature of 29.2℃ in Chongqing is lower than one degree. Extreme high temperature is lower than inland. Guangzhou is only 38.7℃, but Shaoguan is 42℃, which is more than three degrees lower than Wuhan's 42.2℃, Changsha's 43℃, Jiujiang's 4 1.7℃ and Chongqing's 44℃. So there is no heat in summer.

"There is no frost and snow in winter" has been recorded for nearly 30 years, and there is no record of snow. However, according to Ruan Yuan's Guangdong Tongzhi, there were three days of heavy snow in December in Chun Hu in the fifth year (1245), with a surplus of more than one foot, and there was no snow in winter. Daoguang's Nanhai County Records contains: "Thirteen years of Yongle" (14 15), and there is no snow in winter. It only happens once every few hundred years, and there is little frost. According to the observation records in the louver, there is no frost in Guangzhou. But according to the surface temperature, there are 2.4 frost days in Guangzhou. Frost lasts for a short time, mostly in the early morning and will disperse at sunrise, so it is not easy for people to see it. Therefore, today's tropical crops will not freeze to death if they move in. Most of the time occurs in 1 month, which is the morning after the mid-year cold current invasion. The ancients didn't write it down in detail, so it was frost-free. In fact, there are years without years, and there are years that are not heavy. For example, it is rare to see three days of heavy frost in June of 1.955. That year, the surface temperature of Baiyunshan Farm was -6.0℃, and the still water turned into borneol. Sweet potato, banana, pineapple, papaya and litchi all froze to death. At 8 o'clock, the frost began to dissipate. The old saying "There is no frost in Guangdong" is well founded.

The situation that the seasons are unknown still exists today. It's cool when it rains in summer, and my clothes are shaking when I return to the south in late winter. Evergreen all the year round, often flowering. There is no real victory. If the average temperature (that is, the waiting temperature) is above 22℃ every five days, and there are 39 days in Guangzhou, it can be seen that the summer is long and the winter below 10℃ does not exist. That is to say, the seasons in Guangzhou are long summer to autumn, autumn to spring, spring to summer, and winter does not exist. Therefore, the four seasons in ancient Guangzhou can be described as "long summer without winter and continuous spring and autumn". Therefore, it is more appropriate to divide it into dry season and rainy season. That is, the distinction between spring and summer as rainy season and autumn and winter as dry season is clearer than that between seasons.

"Evergreen trees" means that forests are mostly evergreen trees, and so are today. At present, the Woods near Guangzhou can be called tropical monsoon rainforest. This forest is dominated by evergreen trees. Because in frost-free period or frost-free period, leaves can not be shed to avoid the cold, and it can grow (waiting for the temperature to be 10℃), buds, leaves, flowers and so on all year round. It won't freeze to death, trees don't need to sleep and be cold-resistant, and it rains in winter, so they grow well.

"Flowers bloom in four seasons" is due to the hot and humid climate in Guangzhou, and the flowering period can reach twice (such as pineapple and pineapple). ), so it seems that there are flowers in all seasons. In fact, because the flowering period is different, the flowering period is long (from March to half a year). For example, magnolia still blooms in January, pineapples that bloom twice a year, pineapples that bloom three times a year, bananas that bloom all year round, and so on. All the months are formed. Even the coldest February has many flowers. The flower market events in Guangzhou since the early Qing Dynasty can illustrate this point. February (January of the lunar calendar) is the coldest period, but there are many flowers in the flower market at this time. And the north is the yellow scenery of Wan Li. According to ancient records, after the flower market flourished, it became popular because foreign businessmen wanted fragrant flowers to make tea. Zhang Xintai's trip to Guangdong: "At the end of each year, there are two doors in Guangzhou, selling bell flowers and daffodils into the market, like clouds and small people, selling a few seats to entertain guests for the New Year." At the same time, Xu Chengpu, a native (salty and roommate), has a poem "Miscellaneous Poems at the End of the Year": "The Shuangmen Flower Market is the narrowest and full of reeds. In the eleventh year of Tongzhi (1872), the sequel to Nanhai County Records said: "The flower market is in front of the vassal government (that is, in front of the finance office), with bright lights, bright moonlight and fragrant flowers, and it attacks You Mei at night. "It can be seen that the flower market has existed since ancient times. Centered on Line 13, Paddle Road, Shuangmendi and the first two places of Finance Department. Peony, peony, plum, peach, kumquat, orange, camellia, cockscomb, bell, narcissus and so on are all sold in large quantities. Peony, from Shandong, blooms only in Grain Rain, but in beginning of spring, Guangzhou, with a difference of five solar terms. Judging from today's suburban flower fields, professional flower farmers, bells ringing in Qingyuan, and Huashan specialty in Huaxian, Zhaoqing and Sihui, the phrase "flowers bloom all year round" is still correct. The situation is similar to that in the early Qing dynasty, except that today's flower market has increased varieties (such as silver willow and chrysanthemum) and its location has also expanded. For example, it has been more concentrated since the opening of Paddle Road in Shifafu (1918-1919), and women also come to see the flower market: Guangfu South and Xiang Yang Lane. The bottom of the double doors extends to Xihu Road and Education Road. 1960, two flower markets, Dongchuan Road and Tongfu Road, opened. Therefore, the "Lingnan Flower" in Guangdong New Language should not be the season and climate. In October, Mei Ju bloomed. Chrysanthemums also have flowers in the first month. It is also one of the four seasons phenomena.

"Field harvest" refers to the annual production of suburban fields. In winter, crops are no longer planted in the north, but still planted in the south. For example, winter in the suburbs is the peak season for vegetables, and many fish ponds, fruits and sugar cane are harvested in winter. There are many crops planted in winter, which is similar to today's situation. For example, "Zhang Fuzhi" said: "Panyu has two crops, harvesting oil seeds, dyeing three blue, or tree turmeric, or vine green sweet potato. When harvesting in Daiwada, it is burned with seawater. In Pingfu Gaogang, there are still many sugarcane, Gibberella, bean grass, fragrant incense, fruits and melons ... There is no waste soil and people have no hands. " This shows the prosperity of agriculture in the suburbs of ancient Guangzhou.

"It's only cool but not hot in the middle of the year" refers to the long summer and continuous spring and autumn. It's cool in autumn and spring, and hot in summer. Therefore, some flowers can bloom all year round (such as pistachio, papaya, banana, etc.). ), some flowers bloom several times, for example, Yang Tao blooms five times, and some people even think that "flowers should not take festivals as the key link". There are chrysanthemums in the flower market, which is different from autumn chrysanthemums in the north, because winter in Guangzhou is autumn in the north, so chrysanthemums can bloom at the end of winter.

"Drought disorder" is also the climate characteristic of Guangzhou. Because it is located in the monsoon region, the airflow alternates between north and south, with the north wind blowing cold in winter and the south wind blowing hot in summer, and the cold and warm airflow in the north and south meets to form a rain area. If the airflow changes, Guangzhou can become a rainy period or rainy period, which is prone to floods and droughts. Because the airflow in the monsoon region is unstable. Among them, especially hurricane rain, a hurricane often turns into a disaster, such as the "Guangzhou Hurricane" in October of Song Kaibao's eighth year (975). It rained for more than twenty feet one day and one night, and the sea rose and the ship was lost "(Song Shi). Five elements "). In the twentieth year of Yongle (1422), there was no hurricane and rainstorm in summer and May, and the sea flooded "(Huang Zuo's Guangdong Tongzhi). If the monsoon is abnormal, there will always be drought. For example, Guangdong Tongzhi said that Shaoxing was sixteen years old (1146); Guangzhou has been dry for a long time. "Panyu County Records" said that in the twenty-third year of Wanli (1596), "the spring drought followed the autumn drought, and the land was thousands of miles away". That is to say, there is no rain in spring and no hurricane in autumn, all of which have become droughts. 1963 for example, there has never been a heavy rain in the nine months from winter to next autumn. What is recorded in ancient books is not misinformation, so water conservancy measures are still very important.

According to the calculation that the average daily temperature in Guangzhou is equal to or greater than 10℃, the total accumulated temperature is about 80000℃, which is the highest temperature area in China, and it is enough for farming all year round. Humidity can be expressed by rain. The average annual total rainfall in Guangzhou is 65,438+0,727.8 mm, which is also the wettest area in China, and it is not inferior to the hot and humid tropical climate in the world, so Guangzhou is classified as a hot and humid tropical area. From the natural forest facies, the forest facies near Guangzhou is also a tropical rainforest type. If the dominant tree species in the forest are not obvious, the people call it "miscellaneous forest" There are many vines, epiphytes, parasitic plants and aerial plants. Tree species are mostly distributed in tropical areas, with roots (kapok, face, banyan, bodhi, etc. ); The ecology of tropical rain forest is like old stems with flowers (such as pineapple and carambola), smooth bark, rotten leaves (such as mangoes and lychees when they just came out), dripping sharp leaves (especially sharp ones, which are beneficial to dripping water) and pincer leaves (the leaves absorb sunlight alternately). Winter is early, but there are still cold waves and rain, for example, in the "flower market", it is always cold and drizzling.

Summer is long, and afternoon thunderstorm (white rain) is also one of the climatic characteristics of Guangzhou. This makes the water temperature in paddy field drop sharply, which is beneficial to early rice. According to today's observation, when the temperature is 33°C (that is, the temperature of summer and summer weather), the paddy field has reached 40°C, which scalds the rice roots, reduces the nutrients absorbed by rice during grain filling, and causes empty grains, especially in sandy land. It can be seen that the white rain in ancient books can make early rice thrive.

Three winters with long eyes and rain coming back to the south also indicate the warm winter situation in Guangzhou. Sunny days in winter can last for half a month, with the highest temperature of 22℃ and the lowest temperature of 12℃ during the day, so it becomes the weather for shaking fans in winter. If there is no cold current in winter, the local weather in Guangzhou is still very hot. Labor is sweating, so it is called "sweating in winter rain". "Guangdong New Language" said: "It's warmer in three winters" and "It's cold in winter and warm in two or three days", which also pointed out this situation.

It is rainy in spring and summer because at the turn of spring and summer in Guangzhou, it happens that the air conditioner in the north and the heating in the south are in contact here. So the warm air flow is cooled by the cold air flow, and the water vapor condenses into rain, which is the cooling rain on the front where the cold and warm air flows contact. When this cold and warm air front stays in coastal areas, or Luoping Mountain is blocked, a wide rain area (rain belt with a width of 200-300 kilometers) can be formed, which makes Guangzhou rain for more than ten days and causes floods.

; "It's cold and rainy in spring" means that cold air goes south to turn heating into rain, which is also called "fighting from south to north" weather. There are indeed many records in ancient books that lewd rain is a disaster. For example, in the forty-third year of Jiajing (1564), "it rained from the first month to August, and obscene rain destroyed crops" is an example.

The cold wave invaded, but it still couldn't affect the tropical characteristics and became a unique place in Guangzhou. If there is a cold period in winter, it can kill soil worms and cause rainfall, and plants in the north can move south, which plays a great role in production. The proverb says that "the fields are full of crops and millet in dry and wet years in winter", which indicates the benefits of dry and cold tides and wet cold waves to agricultural production. Therefore, Guangzhou is a beautiful and rich tropical monsoon city, which enjoys a history of thousands of years in China and is also famous in the world today. That is to say, it is related to its climate characteristics. Shiji cloud; "Panyu is also one of the cities." A combination of pearls, silkworms, rhinoceros, gourd, fruit and cloth. "More than 2,000 years ago, Guangzhou has become a concentrated capital rich in tropical products. Later, it developed into a distribution center for ivory, copper and silver. Geography of Hanshu said: "In offshore areas, there are many rhinos, elephants, turtles, pearls, silver, copper, fruits and cloth. "Compared with the time recorded in Historical Records (when Emperor Wu of the Han Dynasty), there are more trade projects such as silver and copper.

Professor Zhu Kezhen of our country pointed out that the tropics of our country are in the south of Wuling Mountains. In his book Phenology, he said: Lingnan can be said to be the southern boundary of China's subtropics, and the south of Nanling can be called tropics. The characteristics of the tropics are: in other words, in the tropics, the difference between dry season and rainy season is more prominent than that between winter and summer ",but Guangzhou is a beautiful tropical city, and climatologists also admit this.

Of course, there are many mountains near Guangzhou, so the distribution of temperature and rainfall is uneven, generally between1500-1800 mm. For example, in Huangpu and Fuxi Port, because the north is blocked by Baiyun Mountain and the south is blocked by urban abutment, it becomes a less rainy area below 1550 mm, which is beneficial to harbor construction. Baiyun Mountain has a high terrain, and the north-south airflow rises in the mountains and condenses into rain. The rainfall is above 1800 mm ... Guangzhou has a bright terrain and smooth airflow, and it has also become a rainy area, with a height of1710 mm.