At 8 a.m., the air quality index (AQI) at the Hanoi University of Science and Technology gate station on Giai Phong street was 228, categorized as very unhealthy. Pollution at this station began rising to this level at 3 a.m. The monitoring station at Nhan Chinh park on Khuat Duy Tien street also recorded an AQI of 182, an unhealthy level, while the 556 Nguyen Van Cu station registered 177.
IQAir ranks Hanoi as the 5th most polluted city globally with an overall index of 190, trailing Kolkata (India) at 220. The system also displays dozens of points with very unhealthy air quality across areas like Thanh Xuan, Minh Khai, Vinh Tuy, Ha Dong, and Tay Ho.
Previously, Hanoi's air quality remained moderate to poor for several days as continuous cold air strengthened, facilitating dust dispersion. However, since yesterday, with stable cold air and a significant day-night temperature difference creating a temperature inversion, pollution levels began to increase.
AQI is an air quality index that reflects pollution levels and their impact on human health; the higher the index, the greater the potential impact. According to authorities, current air pollution is primarily due to fine particulate matter PM2.5.
 |
Air pollution in Hanoi. Photo: Hoang Giang
Beyond Hanoi, very unhealthy air quality was also recorded on Nguyen Van Linh street in Hung Yen city, Hung Yen province, with an AQI of 214, and at Thai Binh bridge in Thai Binh city, with an AQI of 215. Some other areas also reported high pollution levels, including Quan Trieu (Thai Nguyen) and Hai Duong (Hai Phong).
The Department of Environment (Ministry of Agriculture and Environment) forecasts that Hanoi's air quality will remain very unhealthy tomorrow. Meanwhile, the air quality forecast system of Vietnam National University, Hanoi, predicts that Hanoi is entering a pollution wave until 14/1, with peak pollution expected on 11/1.
 |
Air pollution map in the North, morning of 9/1. Photo: VietnamAir
Vu Huu Liem, Director of the Center for Agricultural, Resources, and Environmental Monitoring, National Remote Sensing Department, stated that the unit is monitoring air pollution hotspots using two methods: high and super-high resolution satellite imagery. This approach allows for comprehensive coverage of the entire city, tracking construction areas and craft villages, and detecting emission signs like chimneys or open burning sites.
The center also utilizes Matrice 300 RTK unmanned aerial vehicles (drones) for detailed monitoring and real-time response to emerging situations. Drones capture close-up images at hotspots such as waste burning, straw burning, or localized emissions, providing direct data for inspection and enforcement efforts.
Through these efforts, functional units have identified 68 construction sites and 14 plastic and steel recycling craft villages requiring focused monitoring. Many construction projects are sources of dust if not properly shielded and controlled according to regulations.
Gia Chinh
