On the afternoon of January 27, the IQAir application ranked Hanoi in the group of 6/10 air-polluted cities in the world with 180 - a red threshold. With this index, sensitive people may have serious health problems and normal people may have health problems. From early morning, Hanoi's sky was covered with a dark air, this situation lasted all day, causing many people to clearly feel discomfort. At some times, some areas in Hanoi have purple air quality - a very bad level.
Not only in Hanoi, some provinces and cities Hung Yen, Thai Nguyen, Bac Ninh, Phu Tho, Ninh Binh and Hai Phong also have bad air quality today.
The reason is said to be that cold air is weakening in the North, windy conditions combined with the phenomenon of heat reversal make air pollutants such as fine PM2.5 dust unable to spread, causing serious air pollution.
Talking to Lao Dong Newspaper, Assoc. Prof. Dr. Hoang Anh Le - Head of the Department of Environmental Management, Faculty of Environment, University of Science, Vietnam National University, Hanoi, according to common rules, air pollution in Hanoi and northern provinces and cities usually occurs from about October to April of the following year. The reason is that during this period, weather conditions such as heat reversal and humidity make pollutants difficult to diffuse, leading to declining air quality.
From about June to June, air quality may improve slightly. The weather turns to summer, the wind regime changes, high temperatures increase air convection vertically, thereby creating conditions for dispersing and washing away pollutants, thereby improving air quality compared to winter and early spring.
According to Assoc. Prof. Dr. Hoang Anh Le, bringing air pollution to a safe level is the responsibility of the whole community. Instead of waiting, each individual also needs to protect themselves from the current pollution situation.
People should create a habit of updating current status information and air quality forecasts to have personal solutions. If there is uncompulsory work, people can temporarily postpone going outdoors, avoiding pollution times.
For example, people's exercise habits often take place in the morning and evening, but these are the most serious times of pollution due to heat reversal. People should use quality masks to minimize the impact of air pollution," Mr. Hoang Anh Le advised.
