To begin with, an index forecasting and early warning system of dust-haze is supposed to be set up. Foundation optical observation points should be established matching the satellite remote sensing data and monitoring the optical thickness of aerosol should be carried out as well. Meanwhile, set up observation stations to observe the horizontal and vertical visibility for the direct public service about dust-haze; carry out the detection of atmospheric boundary layer for timely awareness of the relationship between the characters of boundary layer like temperature inversion and dust-haze; get to know about the effects made on the structure of atmospheric boundary layer by industrialization and urbanization; improve the accuracy of dust-haze forecasting and enhance the ability to monitor and prevent the dust-haze.
Strengthen the surveillance of solar radiation and evaluate the effects of dust-haze on agricultural production and climate changes, etc. Only when the establishment of dust-haze forecasting system is combined with dynamic controlling system of pollution discharging and decision making system of controlling emissions from sources of pollution, can dust-haze be effectively coped with. Concerning the situations we know now, urbanization and industrialization are main triggers of dust-haze, while one of the climatic features of the appearance of dust-haze is that there is a stagnant area where it happens. Some foreign developed countries implement dynamic regulation and control of social production based upon various climatic conditions, which is to adjust the total amount of pollution sources in essence. For example, once the stagnant areas are detected somewhere in the United States, all the industries will be controlled on gas waste emission, while when the atmospheric condition is good and the air can well spread, the emission is not limited.
Secondly, strict regulations on emissions of motor vehicle exhaust and industrial gas should be enacted so as to remove or decrease the harm dust-haze does to cities. At the same time, cities should coordinate with each other in groups to prevent dust-haze. As a regional phenomenon of climatic disasters, dust-haze requires cooperation between regions to be dealt with. Only in this way, can all the management work out.
At last, in urban planning, pay attention to the study of the sinking distance of urban updraft reaching suburbs and lay out the factories with much pollution beyond the sinking distance to avoid the pollutants discharged by them flowing from near the ground to the city; satellite cities should also be built outside the urban heat island circulation to avoid mutual pollution.
The air passage should be reserved for the full consideration of atmospheric diffusion conditions. Urban green space is supposed to be increased to give full play to the environmental benefits of smoke and dust removal, air filtration and environmental beautification so as to purify the urban atmosphere and improve the quality of urban air.
National standards for the main four kinds of atmospheric composition of dust-haze include the aerosol mass concentration with diameter less than 2. 5 micrometers, the aerosol mass concentration with diameter less than 1 micrometers. There are also regulations of aerosol scattering coefficient and aerosol absorption coefficient. As long as one full index is beyond limit, even if the visibility is more than 10 km, it is also called dust-haze. The forecast level of dust-haze is divided into four grades: slight, mild, moderate and severe.
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