The central area of Ho Chi Minh City is covered with fog - Photo: CHAU TUAN
On September 25, the Center for Natural Resources and Environment Monitoring (Department of Natural Resources and Environment) reported results of air quality in Ho Chi Minh City in September, especially from September 19 to 23. the "cloudy sky" phenomenon.
The results of monitoring 30 environmental locations in September showed that the air quality from September 3 to 20, there was a sudden increase of pollutants such as suspended dust, NO 2 , SO 2 , CO .. in days 18 to 20-9.
The highest was on September 20, suspended dust increased by 2.19 times, NO 2 increased by 1.41 times, CO increased by 1.4 times. Especially, the increase of fine dust PM10, PM 2.5 increased from 1.9-2.2 times. This fine dust is recommended to have a great effect on health.
On the cause of the increase in pollutants, according to the Center for Natural Resources and Environment Monitoring, due to the tropical convergence activities combined with the diffuse cold air to make the city always cloudy. sunny. Along with the low temperature base there is large intermittent rain, high air humidity and in the atmosphere there are condensed nuclei, water vapor forms a blind layer.
In addition, because there is no sunlight, there is not enough radiation to heat the ground, creating an inverse heat layer so that the polluted air lying close to the ground cannot disperse. .
Based on domestic and international forecast data, the Center for Natural Resources and Environment Monitoring rejected the cause of air pollution in Ho Chi Minh City due to the impact of forest fires in Indonesia.
The center also said that blindness causing air pollution in the past few days often occurs annually around September and October in Ho Chi Minh City. This phenomenon is also known as photochemical blindness.
To limit the impact of polluted air, the Center of Natural Resources and Environment Monitoring advises people, especially children and pregnant women, the elderly, to limit going out, participating in traffic and other Outdoor sports activities. If you need to go outside, you need to wear a mask, cover all eyes and cover when in direct contact with polluted environment.
At the same time, people remember their eyes and nose with physiological saline, limiting exposure to food and clothing, limiting the use of rainwater.