Why is the air in Hanoi unusually polluted this morning?

On the morning of January 14, Hanoi recorded the most polluted air in weeks. AQI is purple (AQI is over 200, very bad level).

On the AirVisual air quality monitoring page at 7:30 , the average air quality of Hanoi is 229. The index is measured at most monitoring points at the threshold of 200 units. At the same time, Hanoi ranked fourth in the top air pollution city according to this page.

Specifically, the highest AQI area continues to be Tay Ho with an index of up to 296, followed by Trang Tien - 233, Trung Hoa - 223, Thanh Cong - 224, Bac Tu Liem - 229, Hang Dau - 230. Thanh The street also has an AQI score below 200, but it is still very high like Tay Mo - 198, Dich Vong - 196, Kim Lien - 190.

Hanoi air quality on Moitruongthudo.vn morning 14/1. (Screenshots.
On the official monitoring page of Hanoi Department of Natural Resources and Environment at).

Moitruongthudo.vn, air quality is also recorded from poor to very poor. Accordingly, Hang Dau and Minh Khai are the two areas with the highest AQI, respectively 215 and 217, Pham Van Dong - 212. Hoan Kiem area usually has good air quality but today also reaches 195, USA. Communism - 191, Tay Mo - 181.

This is the most serious air pollution since early 2020. From 1/1, air quality in the capital remained in the range of about 150 units, until today there are many points with AQI levels above 200. .

Talking to PV, the representative of Hanoi Department of Environment Protection said that the light air quality on January 14 was seriously reduced due to adverse climatic conditions . The change of heat background, abnormal humidity causes pollutants to "lock in" and not escape from urban areas.

"From yesterday, the hot, humid wind in the South China Sea swept in together with the cold air coming in, along with the impact of the convergence strip that caused Hanoi's weather to have drizzle and dense fog. This created barrier layer, causing pollutants to not diffuse, "said the branch representative.

In the coming days, Hanoi weather will still have small rain and thick fog so the air quality has not improved immediately."In the coming days, if Hanoi has more cold wind to increase or all fog phenomenon, the new air quality will be improved , " he said.

The PamAir monitoring page also gives a bad, very bad AQI.(Screenshots).

According to the Hanoi Department of Environment Protection, Hanoi's air quality was quite good last week because it was windy, AQI in many places gave green results. But this week, air quality was reduced due to fog.

Hanoi's air quality is often worst in the early morning , but gradually improving throughout the day, even though there were not many activities causing pollution. The department representative said this was both due to weather conditions and chemical phenomena. Human activities themselves have caused pollution, this process also produces chemicals, which combine with each other in the air to continue to produce fine dust. So early in the morning there was no traffic, no burning of straw, but the air was still poor and bad.

Air quality in Hanoi will remain bad, very bad in the coming days. Hanoi Environmental Protection Department recommends that people need to protect the health of their families and loved ones, limiting exercise, working outdoors, and wearing masks.

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