Air Pollution In Beijing Environmental Sciences Essay

Air pollution is the substances that accumulated in the atmosphere, which will endanger human health or produce other measured effects on living matter and other materials. [1]Air pollution is mainly emitted from the exhaust of motor vehicles, the combustion of fossil fuels as well as the burning process of coal and oil. As can be seen, the production of electricity generates the most of the pollution through coal burning.

Generally speaking, pollutants can be in the form of solid particles or gases. In addition, they may be natural or man-made. [2] Pollutants in the air can be classified as either primary or secondary. Usually, primary pollutants are substances directly emitted from a process by human or natural sources, such as carbon dioxide and carbon monoxide, dust, sea salt, smoke from forest fires, ash from a volcanic eruption and chemicals from human activity. (See picture1.1)

Picture1.1 Sources of primary pollutants

Secondary pollutants are not emitted directly, they occur when primary pollutants react with atmospheric gases to make new, hazardous substances. An important example of a secondary pollutant is ground level ozone. [3] However, some pollutants may be both primary and secondary: That is, they are both emitted directly and formed from other primary pollutants.

As is addressed in an overview by World Bank of the 20 cities exposed to highest concentrations of particulate matter, which are tiny subdivisions of solid or liquid matter suspended in a gas or liquid, quite a lot of Chinese cities were mentioned, as Beijing is the sixteenth. In fact, not only the concentration of particulate matter, the overall environmental situation of Beijing is indeed a serious problem. Since the mid-1960s, industrialization took the place of agriculture and became China’s primary economy. However, the pollution generation and resource depletion followed, which directly contributes to environmental degradation. The high density of fine particulate matter, ozone as well as SO2 and NOX is the major air problem in China.

When it comes to the effects of air pollution, the damages to human health, vegetation and materials fully account for the reasons why it is important to pay attention to air pollution management. Exposure to these air pollutants has been associated with the increases of mortality and hospital admissions due to respiratory and cardiovascular disease. In fact, air quality management is not simply a euphemistic synonym for air pollution control; rather it represents a well defined process or rationale for establishing and enforcing regulations governing emissions of a wide array of pollutants from diverse urban and rural sources.

Beijing, a typical representative of rapid developing cities, is an example to illustrate the measures that are applied in urban air pollution controlling and management concerned with a sustainable perspective.

Conclusion and Limitation

Conclusion

As can be seen from this dissertation, the most serious air pollution in Beijing is the concentration of PM10, which is mainly from dust-soil, coal burning, construction, vehicle exhaust emission, waste incineration, concrete manufacturing, metal smelting industry emission, as well as urban road traffic. In addition, because Beijing is located at the downstream of Mongolia and Inner Mongolia which are the source areas of the dust storms, and therefore makes the density of PM10 more complicated. In addition to the PM10 problem, the influences caused by O3 and SO2 could not be ignored. High temperature and relative humidity conditions in summer accelerate the transformation of air pollutants, which results in high concentration of O3. While in winter, high demand of coal consumption leads to the dramatic increase of SO2 concentration. Due to the damages such as human health, vegetations and materials, caused by these air pollutants, the municipal government of Beijing starts to pay more attentions to this aspect.

To reduce the air pollutants in Beijing, a more reasonable transportation system had been implemented already. For example, the new city planning called “Two Axles, Two Corridors with Multi-centered” was adopted by the government, which could divide the traffic flow effectively during the rush hour. This leads to the reduction of air pollutants from vehicles when they are at idle. Moreover, public transportation like bus, light rail, and subway are encouraged, the amount of such public transportation is increasing, and light rail and subway were sped up several times. When the usage of public transportation is at an increasing trend, trips by private cars are at a decreasing tendency, and then the emissions from vehicles reduced. What else, the quality of vehicle fuel was also improved, Euro 5 standard tends to be adopted around 2012 in Beijing, the content of sulfur in Euro 5 standard for gasoline and diesel is less than 10 ppm. Beijing municipal government also carried out a lot of incentives on vehicle retrofit, scrappage and purchase to make the on-road vehicles cleaner and emit less air pollutants. Apart from traffic system, there is also transition in energy system. For example, government encourages the usage of renewable energy such as nuclear, solar, wind, biomass, and hydrogen, etc. Economic incentives are applied to encourage the enterprise to invest in the renewable energy. For customers, there are discounts when purchase the electricity that produced by the renewable energy. What is more, green planning is also important in controlling the air quality in Beijing, because trees can absorb air pollutants. And vegetation can also conserve the soil, which would improve the dust storm situation.

Although the air pollution level is still high compared with some European countries, it is developing at a satisfied trend with these efforts from municipal government of Beijing, which means a gradual improvement of air quality every year.

In the August of 2008, the average air pollution index was about 56, which was 30% lower than API 80 at the same period of last year. The PM10 concentration during the Olympics stayed at a satisfied level, and there were even 9 days, in which, the concentration of PM10 came to be lower than 50 micrograms per cubic metre, achieving the WHO air quality target. With regards to the density of O3 in this period, the mean value in the daytime came to 42 ppb, which was the lowest point during these three years. These improvements provided a sound environment for the Beijing Olympic Games.

Limitation

Before the 2008 Beijing Olympic Games, Beijing municipal government carried out a set of phased measures and policies such as the odd-even day vehicle operation and closure of some construction sites. There were also restrictions for the coal-burning facilities. The results of these policies were significant, which made the air quality during the Olympics even achieve the WHO air quality target instead of the WHO interim target for developing countries. However, from the perspective of author, air quality during Olympics has its particularity, and the specific measures that were applied to improve the air quality during this period have their limitations when continue after the Olympics. For example, coal is still the primary energy in China and this situation will last a very long time in future. In addition, coal burning industries could not be restricted too much, which may affect the economic growth significantly. Therefore, attentions should still be paid to the general policies or measures the author mentioned above. Developing a better city map and improving the vehicle fuel quality are necessary. The encouragement of public transportation and renewable energy can contribute to air quality. Furthermore, improving the efficiency of energy and expanding the green areas in urban area of Beijing should be advocated by government and citizens. These measures are mainly applied within Beijing, in the author’s opinion it is not enough. As is propounded that the surrounding provinces Tianjin, Hebei, Shandong, and Shanxi contribute a lot of air pollution to Beijing through the activities such as rural biomass burning, which is an important contributor to fine PM concentrations. The emitted air pollutants pervade the entire region and add to the local pollution in Beijing during transport on the prevailing winds. These four provinces are also the most polluted provinces in China. [68] So in order to improve the air quality in Beijing, the measures should not only be implemented in Beijing, but also applied in the surrounding provinces. Further researches and investigations of the surrounding provinces are of consequence needed.

Furthermore, the whole dissertation is based on the analysis of relative literatures, without any research activities such as questionnaire and interviews, and this may make the dissertation less realistic. To improve this situation, more research methods such as empirical study and observations should be encouraged if available in the further research. What is more, sometimes the opinions and conclusions from the authors of the relative literatures may be subjective which would influence the analysis results. As a student at the university, both the analysis ability and research ability are sometimes not skillful enough for academic work.