Weather experts comprehensive analysis of the heavy rainfall of 7.21 “

Sun Jun Accept the China Meteorological Association, Xinhua interview. (Chong Bai Yushe)
Beijing precipitation at 10 o’clock on July 21 to 22 06 Figure

July 21, Beijing experienced torrential rains, resulting in urban waterlogging, causing part of the mountain mudslides and other disasters and lead to casualties and property losses, caused widespread concern in society as a whole. Why such a major unexpected rare weather will to Mengxi empire? It’s “extreme” what? The meteorological department what had been done in the heavy rain? The public and how to strengthen self-protection under heavy rain? With these questions, the reporter interviewed the Central Meteorological Station chief forecaster Sun Jun.

11 weather stations, rainfall exceeded extremum seven eight on the power of filling

Correspondent: The Sun chief, hello. First heavy rain the general situation.

Sun Jun: July 21 to 22, torrential rain affected areas is very broad, Beijing, Tianjin, Hebei The northern and northern Shanxi process of a wide range of heavy rainfall. Beijing the city’s average rainfall of 190.3 mm, Shijingshan mode port up to 328 mm, the city’s largest rainfall in the town of Fangshan District, Hebei, reached 460 mm, heavy rainfall orders of magnitude. In addition, Beijing 11 weather stations observed rainfall exceeded since the establishment of the historical extremes.

of this storm is rarely seen in history, due to rain, rainfall, Beijing appears serious urban waterlogging, a serious impact on city traffic, some medium and small rivers and reservoirs, flood, according to the Secretary for the Ministry of Civil Affairs disaster relief message. on the 21st since the Beijing rainstorm floods have caused 37 deaths, seven were missing.

Reporter: Beijing almost every year to this time are prone to some heavy rain, what are the reasons?

Sun Jun: weather there is a saying called “seven eight , late July and early August, this time in North China into the rain falling in, prone to rainfall concentrated, the greater intensity of rainfall. And our entire rain belt as the season runs from south to north, push the law coincide, that is, from the earliest before the flood season in South China to the southern rainy season, to the current rainy season of North China.

heavy precipitation is mainly due to the abundant water vapor conditions. China is a monsoon climate, heavy rainfall when the monsoon northward to North China this zone to provide sufficient moisture supply conditions. Before the rainfall, the weather in Beijing is very hot, the water vapor content of air is very large. We estimate that the accumulated water vapor content over the atmosphere in Beijing has reached the order of about 50 mm, if not on the supply of external water vapor, pure air water vapor to descend to the ground is enough to achieve a rainstorm order of magnitude.

rainfall, strong rain, a wide range of impact of weight to some “unimaginable”

Reporter: on the 21st rain-soaked around the ocean, two days before and after 20 and 22, the weather in Beijing is very fine, some users do not understand why the rainfall is not continuous relative, but this short period of time extremely sudden heavy rainfall ?

Sun Jun: Indeed, the strong short-term rain is one of the rainstorm notable feature. Specified in the meteorology, precipitation in the 24 hours of heavy rainfall of 50 mm or more known as the “storm”, but this time in some areas rainfall in one hour more than 50 mm, the the Pinggu han valley even up to 100 mm, the rainfall intensity large beyond imagination.

why? Water vapor conditions just mentioned, just everything is ready wind, a weather system, makes this region of warm air rising, will produce precipitation. The Beijing and other places heavy rainfall is the case, the effect of cold air eastward southward and strong weather system water vapor to produce intense upward motion, coupled with the atmospheric stratification is very unstable, the more intense upward motion, condensation speed accelerated, while the air is nearly saturated, resulting in a high rainfall efficiency.

Reporter: Beijing history of recent years there have been several similar heavy rain? Compared with them, the salient features of the heavy rain, “extreme” is reflected in what?

Sun Jun: most recent one on June 23 last year, Beijing is also found a larger process of heavy rain, urban average of 73 mm, the local also appeared in more than rainfall of 100 mm, 215 mm, the local maximum rainfall intensity of 128 mm per hour or even more than this process. But that rainfall time is short, torrential rain is not evenly distributed, only individual sites in more than 100 mm rainfall, but mainly concentrated in urban areas; and this in addition to Yanqing, Beijing more than 90 percent of the administrative regions of rainfall are more than 100 mm, the average rainfall is well above last year. In addition, in recent years, Beijing also have taken place in several local more than 100 mm rainfall.

Generally speaking, the “7.21″ storm rainfall, rain, a wide range of heavy impact in some areas day rainfall even up to or exceed the average annual rainfall These are the “extreme” manifestation of extremely rare in the history of Beijing.

extreme weather standard does not single rainstorm process is pulled

Reporter: In recent years we have always said that “extreme weather”. What kind of case can be defined as “extreme weather”?

Sun Jun: meteorology, extreme weather will have its own standards and data processing method is simple to understand, from a public point of view, the “extreme” means rare, and occur low probability. Rainstorm, for example, for a region, since on the meteorological data, it accumulated a certain time sequence of the heavy rain observation data, rainfall in history that a rainstorm large value of 5% value range , it can be called extreme weather.

Reporter: The Beijing encounter such a rare rainstorm process will lead to the standard of extreme heavy rain was pulled?

Sun Jun: If the process of this heavy rainfall often appear at a later time, it is possible that standards will be pulled. But only occasionally, once the process and not pulled up to the standard of “extreme weather”.

heavy rain forecasting difficult meteorological department rolling service fully address

reporter: the rainstorm, the meteorological department to take measures to deal with?

Sun Jun: Beijing Meteorological Bureau reported earlier this prediction from the 20th, issued two thematic prediction, pointing out that evening into the night on the 21st heavy rain in some areas of heavy rain. 21, the municipal meteorological observatory day firing five warning 18:30 rainstorm warning level rose to orange, and has started four to two emergency response, strengthening the duty, the top command, scroll Services.

period, the municipal meteorological observatory released to the relevant departments of the municipal government, City Flood Control Office and the Authority to pay five important weather reports, publish the rainfall table of the city part of the meteorological observation station and the city’s rainfall distribution in Figure 18, and and Local Taxation study issued jointly by the three early warning of geological disasters. For the hardest hit Fangshan District, Bureau of Meteorology to take the hourly phone report once every 3 hours updated once a way to report to the District Government.

In addition, the department emergency response quickly start. Timely response to the municipal government and district and county governments in accordance with the prediction, early warning signal level, linkage, take a range of implications of measures to deal with and dispose of heavy rain.

the Central Meteorological Observatory began the afternoon of the 20th blue rainstorm warning issued, 21 noon to upgrade to yellow, to strengthen encryption in consultation with the municipalities, and regions, alert warning. Overall meteorological department released early warning of this process is early warning level is relatively high.

to strengthen self-awareness should not leave things to chance and careless

the

Reporter: meteorological department in advance forecast out of the process, but casualties and property damage occurred. From the public point of view, you feel the need to strengthen the understanding of which aspects of severe weather?

Sun Jun: the public to directly face of severe weather, should raise awareness of prevention, recognizing the seriousness and danger of the extreme weather, more than understanding of science knowledge to protect yourself. For example, if the meteorological department issued the warning information is received in advance, or to see the heavy rainfall has begun, it should try to avoid the car to go out, see the low-lying areas of serious water to be evacuated as soon as possible to avoid the danger, not of luck trying to Been to turbulent flow.

by the threat of flooding, if there is enough time, in accordance with predetermined routes, organized transfer to the hills, highlands, etc., to the fullest possible use of the vessel; surprise, has been surrounded by flood raft, door panels, wooden bed, a water transfer. If the flood comes too fast, it was too late to transfer to climb the roof, the building houses, trees, walls, temporary hedge, waiting for rescue, not a single swim transfer. In the mountains, if even the heavy rains, flash floods will be easy to outbreaks, should be taken to avoid cross the river to prevent flash floods washed away, but also pay attention to prevent landslides, the Rolling Stones, debris flow damage.

Reporter: your next period flood control recommendations What is it?

Sun Jun: on 25-26 July in North China will also have time rainfall forecast in some areas of moderate to heavy rain in some areas may produce heavy rain . Also present in seven of eight on flood control and the critical period of late rainfall in some areas may still be heavy rains or heavy rain, related departments and the public still need to remain vigilant to enhance preventive measures can not be careless. (China Meteorological Reporter Lai Min Xinhua reporter Gai-Ping)

share to: