China News Service, Beijing, January 13 (Reporter Ruan Yulin) Since January 10, large-scale, high-intensity sand and dust weather has occurred in northern China. Affected by sand and dust weather, as of 20 o'clock on January 12, more than 20 cities The hourly value of the air quality index exploded. Among them, the hourly concentration of Jinchang PM10 (inhalable particulate matter) exceeded 2000 micrograms per cubic meter.

　　According to the analysis of experts from the National Center for Air Pollution Prevention and Control and Cooperation, starting around noon on January 10, sandstorms occurred in the border areas of southern Mongolia and western Inner Mongolia.

Under the action of the strong northwest wind, the first air mass carrying a high concentration of dust moved southward along the Shaanxi-Gansu-Ningxia area from the night of the 10th to the morning of the 11th, and spread to most of Henan, central and western Shandong and northern Jiangsu on the 11th.

The second sand dust traveled from the middle of Inner Mongolia to the North China Plain from the afternoon of the 11th to the morning of the 12th, and affected most of Shanxi and the central and northern regions of Beijing, Tianjin and Hebei during the day on the 12th.

The third sand dust formed at the junction of China and Mongolia in western Inner Mongolia on the evening of the 12th. It is stronger than the first two and is moving to the southeast.

　　Monitoring shows that the sand and dust weather has a high intensity and a wide range of impacts. The air quality along the way deteriorated rapidly. Some cities in Henan, Shanxi, Shandong, and Hebei experienced serious pollution within hours, and the primary pollutant was PM10.

As of 20:00 on January 12, among 337 cities at prefecture-level and above, 21 cities including Jinchang, Wuzhong, Wuhai, and Yulin had a PM10 hourly concentration of more than 600 micrograms per cubic meter, and the hourly air quality index broke out. Among them, Jinchang The 10-hour PM concentration exceeded 2000 micrograms per cubic meter on the evening of the 12th.

　　Experts say that this year's dust weather on a large scale is the earliest in the past five years.

The analysis of monitoring data from 2017 to 2020 found that the large-scale sand and dust weather process that affects many provinces across the country usually does not appear until the end of January or February.

This year, the dust weather started in mid-January, about half a month earlier than in previous years.

　　Analyzing the reasons, experts from the National Air Pollution Prevention and Control Center said that the preliminary analysis is related to the recent strong wind, less precipitation, and temperature rise in the sand source.

　　The forecast shows that from the 13th to the 14th, the inland areas of China may continue to be affected by the multi-frequency sand and dust process. The transmission path is western Inner Mongolia-central eastern Gansu-Ningxia-Shaanxi-Shanxi-Beijing-Tianjin-Hebei-Henan-Shandong-Northern Jiangsu and Anhui North-Yangtze River Delta.

Affected by this, it is expected that the cities in the sand and dust transmission route from the west of Inner Mongolia to the west of Taihang Mountain will be mainly polluted by heavy or more pollution. The mountainous cities such as Zhangjiakou, Beijing and Shijiazhuang may have short-term heavy pollution. Other cities in Hebei, Henan, Shandong, and Northern Jiangsu Northern Anhui is dominated by moderate pollution.

　　China Environmental Monitoring Station predicts that from the 15th to the 16th, due to the influence of the systemic cold high pressure southward and the northerly cold air process in the direction of the northeast Bohai Bay, the diffusion conditions will improve, and the impact of the sand and dust process in North China and Northwest China will gradually tend to End.

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