This century, complex regional pollution has afflicted China and its neighbours continuously. YueSi Wang and his colleagues from The Institute of Atmospheric Physics in the Chinese Academy of Sciences have just explained some of the reasons for the drastic levels of air pollution around Asia in January and at several other times recently. Aerosols and trace gases were sampled on the ground throughout central and eastern China. Their useful publication is in Science China Earth Sciences.
We've frequently reported the dire Asian pollution effects on health in articles such as Chinese pollution problems.
This time the worst haze pollution around Beijing produced up to 680Î¼g per cubic metre of PM2.5 particulates on 2 occasions in the month of January. Shiijazhuang and Tianjin produced very similar levels. This was because of an unusual circulation of air and the depression of strong cold air activity, but basically, pollutants were quickly transformed into an aerosol form that explosively grew and sustained the microscopic particles (PM2.5) in the air for a long time. With low wind speeds, these pollutants quickly formed. Nitric oxide came from cars and other fossil fuel combustion and sulphur dioxide formed particularly from burning coal.
The products of these burning episodes were sulphate aerosols and secondary aerosols including an increasing amount of nitrate ions, as oxidation and other reactions on the particle surfaces increased. Sulphate aerosols require iron and magnesium oxides as promoters, with ozone present as the oxidant. All these conditions exist in the heavily urbanising and industrialising Chinese environment, although ZueSi's and others' research is still finding further evidence about these complicated aerosols. Even satellite evidence is helping the understanding of the range and depth of pollution.
We already have many years of tracing forest burning in Asia and the related haze from Singapore to Japan. Now the Chinese can demonstrate that their urban pollution will contribute great regional stress on people, crops and the atmosphere. It's certainly time for international cooperation on how this gigantic health problem throughout our biggest continent can be contained and of course prevented completely. The air is not reliant on nation or sources of pollution. It is free and must remain clear of such apparently permanent problems, even in heavily industrial areas. Everybody in China commented on this January. Let's get these regional pollutions under control, for the good of the people, and then global warming events may stop accelerating so much.
As the paper here states, "synchronous emission abatement policies that are based on integrated planning should be implemented in stages to improve the regional air quality." International agreements also need to be made, given the proximity of industry to borders throughout Asia. Maybe then, at least our lungs can breathe in peace.