The Beijing Center for Disease Prevention and Control issued an advisory on its official WeChat account, urging people with chronic respiratory illnesses to avoid outdoor activities and recommended that commuters wear brightly colored clothes to avoid road accidents amid poor visibility. On days when air quality is good, the PM10 level usually remains below 150 micrograms per cubic meter. The level of PM10 - inhalable particles with diameters of 10 micrometers or less - increased rapidly and reached a peak concentration of 1,667 micrograms per cubic meter around 6 am on Wednesday, according to the Beijing Ecological and Environmental Monitoring Center. Visibility remained lower than 1,000 meters in some parts of northern China as the NMC issued a yellow alert, the lowest in the three-tier weather warning system. The affected areas included the Inner Mongolia autonomous region and Hebei, Gansu, Shaanxi, Liaoning, Jilin and Heilongjiang provinces, besides Beijing and Tianjin municipalities. Satellite images showed that by Wednesday morning, it had covered 854,000 square kilometers, roughly twice the size of the US state of California. The storm, which according to the National Meteorological Center was the strongest in China so far this year, affected several provincial-level regions.

Ī sandstorm that originated in Mongolia on Tuesday swept through vast swaths of northern China, including Beijing and Tianjin, causing heavy pollution, reducing visibility substantially and disrupting public transportation.

The traffic is shrouded in sand and dust as a sandstorm hits Beijing on Wednesday.

Bei jing sand strom