I look this photo of the Red River in Hanoi on a recent sunny morning. The haze in the background is clearly visible. The Air Quality Index (AQI) at the time was 167, which is in the “unhealthy” category. It may very well have been higher in this part of the city. Here is the definition for this range: ‘Unhealthy’ AQI is 151 to 200. Everyone may begin to experience some adverse health effects, and members of the sensitive groups may experience more serious effects. This website (and app) are also useful: PAM Air. Since PAM Air is a Vietnamese environmental services company, the information on both is in English and Vietnamese.
The main causes are gas emissions from vehicles, especially motorbikes and trucks, exhaust from factories, fire as a means of waste disposal, coal-fired power plans, and pollutants from construction sites. The lack of public transportation and the daily traffic jams exacerbate the problem. As this July 2018 Al Jazeera article points out, the pollution peaks from December to February, during the drier months of the year. This is also the time when winds draw dirty air from southern China across the region. Studies have shown that the pollution largely originates from the vast cities of Chengdu and Chongqing. Not surprisingly, the air pollution created market opportunities for companies that sell air purifiers, most beyond the financial reach of the majority of Vietnamese.
The subtitle of this March 2020 article Vietnam’s Big Air Pollution Challenge, which sums up this existential problem, is spot-on: Bold action is needed to address the country’s problem.
Postscript: As of this morning, nearby stations are reporting AQI readings over 350, which is in the “hazardous” range: Everyone should avoid all physical activity outdoors.
Shalom (שלום), MAA