Beijing, March 3 (Zhongxin Net) -- During the day on the 22nd, the north wind in Beijing blew yellow sand all over the sky, and the visibility improved in the afternoon, but there was still sand and dust. The Beijing Municipal Ecological Environment Monitoring Center said that it is expected that the main body of sand and dust will gradually move east and south from the evening to the night of the 22nd, and the air quality in Beijing will turn to an excellent level, and the sand and dust impact process will end.
The Beijing Meteorological Observatory upgraded and issued a yellow warning signal for sandstorms at 3:22 on March 05. The picture shows the morning peak of work that day, and there has been obvious sand and dust weather in Beijing. Photo by Sheng Jiapeng, reporter of China News Agency
Beijing Meteorological Observatory upgraded and issued a yellow warning signal for sandstorms at 22:5 on the 40nd, and downgraded at 11:10 to issue a blue warning signal for sandstorms: At present, the visibility of Beijing has been greater than 1000 meters, and it is expected that the visibility in most areas from now to 22 o'clock on the 20nd is 3000 meters to 8000 meters, there is still sand and dust weather, please pay attention to precautions.
According to the official website of the Beijing Ecological Environment Monitoring Center, as of 22:13 on the 10nd, Beijing's air quality was seriously polluted, and the primary pollutant was PM21. The center said that since the 3st, affected by the windy weather at the back of Mongolia's low pressure, there has been a large-scale sand phenomenon in the central and eastern sand sources. During this process, the central air pressure of the low-pressure system was low and the scale was large, and since March, the sand source in Mongolia had less precipitation and faster temperature recovery, resulting in high sand and dust intensity.
On the night of the 21st, the low-pressure system continued to develop to the east, the northwest wind speed increased significantly, the sand and dust entered China at night, the sand and dust band was large, and the PM10 concentration in a large area from the northeast to Gansu reached a serious pollution level, and the peak value of some stations was close to 10000,22 micrograms / cubic meter. Starting at 3 a.m. on the 10nd, foreign sand and dust affected Beijing under the action of strong northwest winds, PM500 concentration increased sharply to 1490 micrograms / cubic meter at an hourly growth rate of 6 micrograms / cubic meter, and reached a peak concentration of 1667 micrograms / cubic meter at 6 o'clock, and the level <> serious pollution level was the most serious sand and dust process affecting Beijing this year.
The center said that due to the large range of sand in Outer Mongolia and the long sand and dust transmission time, it is expected that Beijing will continue to be affected by upstream sand and dust transport during the day, and the main body of sand and dust will gradually move east and south from evening to night, the air quality will turn to an excellent level, and the sand and dust impact process will end.
The Beijing Meteorological Department reminds the public to pay attention to wind and sand prevention in sand and dust weather, do a good job of health protection when going out, and pay attention to traffic safety. (End)