On July 24, the traffic police directed traffic in a stagnant water section in Langfang, Hebei. According to the Central Meteorological Observatory, due to the influence of Typhoon Abe, heavy rains occurred in eastern Hebei, most of Tianjin and southeastern Beijing from the 23rd to the morning of the 24th. Lu Feng/photo (Xinhua News Agency)
Today, No.10 typhoon "Abe" brought wind and rain to journey to the south, passing through Hebei, Tianjin and other places, and it was stormy everywhere.
This is not the first time that a typhoon has come to the north. According to the statistics of the Central Meteorological Observatory, there have been typhoons like Abe that landed in East China and went all the way north since the meteorological records, including No.7 typhoon Frida in 1984, No.6 typhoon Tim in 1994, No.11 typhoon Winnie in 1997 and No.9 typhoon Mai Sha in 2005.
Why did Typhoon Abe go all the way north and what impact did it have on northern China? The reporter interviewed relevant experts from China Meteorological Bureau.
Why can Typhoon Abe go all the way north with tropical storm intensity?
Typhoon Abe is the 10th typhoon (tropical storm level) this year. On July 22nd, Typhoon Abe landed in Chongming Island, Shanghai, China. When it landed, its wind force was 10, reaching 28 meters per second, and then it moved to the northwest at a speed of about 20 kilometers per hour — —
At 17: 00 on July 23rd, Typhoon Abe moved to Mengyin, Shandong. Around 3: 50 am on July 24th, Typhoon Abe moved into Hebei, and its center was located in Cangzhou City, Hebei Province at about 6 am. At 8: 00 am on July 24th, Typhoon Abe has moved into Tianjin.
Why can Typhoon Abe go all the way north with tropical storm intensity? Xu Yinglong, chief forecaster of the Central Meteorological Observatory of China Meteorological Bureau, said that there are two reasons: First, the route after landing is close to the coastline, which makes half of Abe’s structure stay at sea and half on land. The continuous water vapor and good environment on the ocean help it maintain its "shape"; Second, the terrain is relatively flat. Most areas in Jiangsu and Shandong are dominated by plains and hills, with gentle slopes and small fluctuations, which have little effect on weakening typhoon intensity.
Xu Yinglong said that "Abe" will work together with cold air in the future, and will also affect Liaoning, Jilin, Heilongjiang and other places, bringing heavy rainfall to many places in Northeast China.
Historically, according to the statistics of the Central Meteorological Observatory, in addition to typhoon Mai Sha, typhoons Frida, Tim and Winnie all affected Heilongjiang. At the same time, all three typhoons brought a lot of rainfall in the process of going deep inland.
There have been seven typhoons in history that "invaded" Beijing.
Although Typhoon Abe did not enter the territory of Beijing, due to the influence of its main rain belt which weakened the low pressure northward, rain began to appear from southeast to northwest in Beijing on July 23, with heavy rain in the east and local heavy rain.
According to the statistics of Beijing Meteorological Bureau, from 20: 00 on July 23rd to 9: 00 on July 24th, the average rainfall in Beijing was 23.6 mm, and that in the urban area was 33.3 mm. The maximum rainfall occurred in Yongledian, Tongzhou, with 96.8 mm, and the maximum hourly rainfall intensity occurred in Dongba, Chaoyang, with 46.6 mm at 7-8 o’clock.
Xu Yinglong said that compared with the usual rainfall in the flood season in Beijing, the rainfall brought by typhoon Abe has the remarkable characteristics of strong short-term rain and may be accompanied by lightning, and there may be gusts of about 6 in the eastern region.
It is worth noting that at present, it is likely that it is only the peripheral cloud system of typhoon Abe that affects Beijing, not its main cloud system, and its rainfall intensity is obviously different from the direct impact of typhoon. Xu Yinglong said that because the typhoon’s moving path and intensity changes are affected by many factors such as atmospheric circulation and topography, a little swing in its center position and changes in intensity will cause changes in the rainfall area and intensity in Beijing.
This is not the first time that Beijing has been affected by a typhoon. Today, the Beijing Meteorological Bureau sorted out the "rainfall process affected by typhoons in Beijing since meteorological records were recorded". The results showed that there were seven times when the typhoon weakened and the low pressure passed through or approached Beijing, the time was August 2, 1956, July 27, 1972, August 8, 1984, July 21, 1989 and July 12, 1994.
Take July 29th, 2017 as an example, the 10th typhoon Haitang landed in Fuqing City, Fujian Province, China. From day to night on August 2nd, moderate to heavy rain occurred in Beijing under the joint influence of weakened low-pressure trough and eastward-moving high-altitude trough. From 8: 00 on August 2nd to 5: 00 on the 3rd, the average rainfall in the whole city was 36.7mm, and that in the urban area was 33.3mm..
Since June, typhoons have landed in China.
According to Xu Yinglong, since June this year, typhoon activities in the northwest Pacific and South China Sea have been more obvious and active than in previous years — —
As of July 24, 11 typhoons have been generated, 3.5 more than the same period in history, of which 4 typhoons were generated in June, compared with 1.8 typhoons in previous years; The number of typhoons generated since July is close to the historical level.
At the same time, four typhoons have landed in China this year, which is slightly more than the historical level of 2.1. Except for Typhoon Ayunni, which landed in early June, typhoons Maria, Mountain God and Abe landed in China from July 11 to 22, with relatively concentrated time.
Xu Yinglong said that from the perspective of disaster prevention and mitigation, the typhoons that landed in China this year were mainly concentrated in South China and East China, bringing a lot of precipitation and strong winds to many provinces. Due to the high intensity of precipitation, the impact of secondary disasters such as urban waterlogging, landslides and mudslides is the focus of defense in related areas when typhoons come.
At present, four tropical cyclones have been detected in the northwest Pacific Ocean and the South China Sea, but this phenomenon is not uncommon. Xu Yinglong explained that typhoons are generally generated on the south side of the subtropical high (hereinafter referred to as "subtropical high"). When the subtropical high is strong and the cold air in the southern hemisphere is active, it is easy to generate multiple typhoons at the same time.
According to him, at present, the equatorial westerly wind has advanced to about 160 east longitude, and there is a strong airflow convergence between the easterly wind on the south side of the subtropical high and the equatorial westerly wind. On the satellite cloud image, there will be multiple convective clouds in the northwest Pacific Ocean and the South China Sea, and with appropriate atmospheric circulation dynamics and sea temperature conditions, it is easy to generate multiple typhoons.
Beijing, July 24th
China Youth Daily Zhongqing Online Reporter Qiu Chenhui Source: China Youth Daily
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