THE hazy weather that affected the city recently will run until Saturday, at which point the situation will be improved by rainfall, according to Shenzhen’s environment authority.

Statistics showed the PM2.5 concentration in Shenzhen was 14.2 micrograms per cubic meter on average between Aug. 1-19, 0.2 micrograms per cubic meter lower than during the same period last year. However, starting from Aug. 20, the PM2.5 concentration significantly increased to 35 micrograms per cubic meter and then 34 micrograms per cubic meter Tuesday.

The increased PM2.5 pollution was a result of the accumulation of pollutants and emissions, mainly nitrogen oxide and VOCs, in “extremely unfavorable meteorological conditions,” the environmental watchdog said.

The monitoring results provided by Shenzhen Meteorological Observatory showed rather weak horizontal winds and a highly static weather condition in Shenzhen, which, along with high humidity, are very unfavorable for dispersing pollutants.

The environment authority said the situation could be improved by the rainfall brought by the short wave trough of the monsoon zone that will pass through the city over the weekend. The observatory predicts thunderstorms from Friday to Monday.

The monitoring results in subdistricts showed that the pollution in western parts of the city was more severe than in the eastern areas. Between Aug. 20 and 21, the PM2.5 concentration in Xixiang reached 73 and 88 micrograms per cubic meter. On Aug. 22, the hourly concentration in Minzhi, Pingdi, Xinhu, Songgang and Guanlan surpassed 75 micrograms per cubic meter. The pollution situation has been slightly alleviated by rainfall.

Other cities in the Pearl River Delta area have also faced similar situations since Aug. 20. Many cities in South China have reported hazy weather.

(Han Ximin)