The route of this year's No. 1 tropical storm "Omes" was marked on the map of the Central Meteorological Observatory as early as March 24. Two days later, it weakened and disappeared in the open sea, and did not affect the Chinese waters. For the next 107 days, there was no movement in the active zone of typhoon between 10-20 ° north latitude in the western Pacific until July 12, when the No. 2 typhoon of this year, "Conson", was formed in this zone. As of July 13, there were only two tropical storms in the northwest Pacific Ocean and the South China Sea. Why did the typhoon come late this year? Why are there so few typhoons generated and landed in the first half of the year? In this issue, Ren Fumin, chief expert of the National Climate Center, and Xu Yinglong, chief forecaster of the Central Meteorological Observatory, are invited to answer your questions one by one. 
Ren Fumin, Chief Expert of National Climate Center
Xu Yinglong, Chief Forecaster of the Central Meteorological Observatory 
"Affected by the abnormal atmospheric circulation this year, the position of the subtropical high, which has an important impact on China's summer weather, in the early stage is relatively south, resulting in weak tropical convection in the region, so it is difficult to generate typhoons." "The number of typhoons that landed in China this year may be close to the normal number or slightly less". 
The first typhoon "Konson" that may affect China this year was half a month late
The number of tropical storms generated in the first half of the year is 3.9 less than 5.9 in the same period of the year
Among all weather phenomena, typhoon is probably the most predictable one. The route of this year's No. 1 tropical storm "Omes" was marked on the map of the Central Meteorological Observatory as early as March 24. Two days later, it weakened and disappeared in the open sea, and did not affect the Chinese waters. For the next 107 days, there was no movement in the active zone of typhoon between 10-20 ° north latitude in the western Pacific region. Until July 12, the No. 2 typhoon of this year, "Conson", was formed in this area. According to the prediction of the Central Meteorological Station, it is likely to become the first typhoon to land in Guangdong this year. Compared with the multi-year average time when the first typhoon landed in China, it was at least half a month late. As of July 13, there were only two tropical storms in the northwest Pacific Ocean and the South China Sea. "The number of tropical storms generated is 3.9 less than 5.9 in the same period of the year," said Xu Yinglong, the chief forecaster of the Central Meteorological Observatory. Access details 
Low sea surface temperature and unfavorable atmospheric conditions are the causes of typhoon generation and less landing
"From June of last year to April of this year, the sea surface temperature in the equatorial Middle East Pacific was warmer in a large range. While it was warmer, the sea surface temperature in the western Pacific was normal or cooler." Ren Fumin said that the low sea surface temperature led to the relative stability of the atmosphere, which was not conducive to the formation of typhoons. But this is not the main reason this year. In this year, atmospheric conditions as a key factor hindered the formation of typhoon in the earlier stage. He explained that in previous years, the area between 10 ° and 20 ° north latitude was usually under the control of the tropical convergence zone. Such atmospheric conditions were conducive to the formation of convection, which was conducive to the formation of typhoons. Under the influence of this year's atmospheric circulation anomaly, the position of the subtropical high, which has an important impact on China's summer weather, is relatively south in the early stage. This makes the tropical convection in this area weak, so the formation of typhoon becomes particularly difficult. Access details
Typhoon, more troubles, less troubles
Take Hainan Province as an example. According to meteorological experts, Hainan Province has abundant rainfall, with an average annual rainfall of 1639 mm. There are obviously more rainy seasons and less rainy seasons. It is rainy season from May to October every year. During this period, some typhoons will affect Hainan Province. During this period, the total rainfall of the province is about 1500 mm, accounting for 70-90% of the total rainfall of the year. However, since this year, the average rainfall of Hainan has been only 372.25mm, 31% less than that of many years, and 42% less than that of the same period last year. At the same time, the reservoir water storage has also decreased. At present, the reservoir water storage in the province totals 3.1 billion cubic meters, more than 400 million cubic meters less than last year. The lack of precipitation directly led to drought in Hainan. According to the relevant person in charge of Hainan Provincial Department of Agriculture, the continuous hot and dry weather has caused serious losses to Hainan's agricultural production, and 5 million mu of tropical crops across the province have been damaged, especially rubber and betel nut. The continuous high temperature not only led to a significant reduction in rubber production, but also created good conditions for the mass propagation of pests, leading to a large outbreak of rubber tree scale insect damage, causing a large area of rubber trees to lose leaves or wither, and many rubber plantations were forced to stop cutting, causing great economic losses to rubber farmers. In addition, 400000 mu of 1 million mu areca in the whole province were affected by drought, and the loss of output is estimated to be about 5000 to 6000 tons. Access details 
The number of typhoons that landed in China this year may be close to the normal year or slightly less
By the afternoon of July 13, Typhoon "Conson" was approaching the eastern part of Luzon Island in the Philippines at a speed of 20 to 25 kilometers per hour. The Central Meteorological Observatory predicts that it will land in the east of Luzon Island at night on the 13th, with a slight decrease in intensity. Then it will cross the south of Luzon Island and enter the South China Sea. After entering the South China Sea, its speed may slow down, but its intensity will strengthen again. It may land in the area from central Guangdong to northeast Hainan from the night of the 16th to the afternoon of the 17th. This will probably be the first typhoon to land in China this year. Xu Yinglong said that due to the fewer typhoons generated in the early stage, the number of typhoons generated in the northwest Pacific and the South China Sea this year will be less than usual, about 21 to 23, or 4 to 6 less. "When the SST situation turns to La Nina in July and August, the atmospheric circulation situation will be adjusted". Ren Fumin predicted that the circulation situation will be conducive to the active development of typhoon. Xu Yinglong also said that the number of typhoons that landed in China this year may be close to the perennial or slightly less. Access details
epilogue
Although the track of typhoon can be traced, human beings still know too little about the factors behind the formation and development of typhoon. Social development has made great strides in disaster prevention and reduction. At the same time, scientists are also persistently studying the explanation behind the weather phenomenon. Maybe one day, human beings can really use typhoon to turn it into endless resources.
