| In recent years, the air quality pollution situation of Beijing-Tianjin-Hebei region is grim, especially heavy pollution process occurs frequently, this causes serious harm to public health, affects the harmonious development between economy and environment. In the current air pollution control measures, the construction and development of air quality forecasting and early warning systems has become our response to atmospheric environmental issues important methods. At present, many regions and cities have established a routine air quality forecasting and early warning systems in China, however, the research of real-time forecasting system of pollution sources to achieve the source regions and industries of pollution is less.In this paper, the Beijing-Tianjin-Hebei region recognition system of pollution source has been established, which core is the particulate matter source tracking module PSAT in the regional air quality model of CAMx. The current system has achieved daily operation, it can give prediction and real-time analysis of source of PM2.5 for the next three days in Beijing-Tianjin-Hebei region every day. Using this system to simulate the Beijing-Tianjin-Hebei region throughout the year of 2014, we receive the level of the grid resolution of 36 km and 12 km respectively double nested meteorological and pollutants concentration results, comparing with observed data to evaluate simulation result. Picking on January 11 to 25 of 2014 as the research period, We use the system to study the reduction effect of two cuts and situation to peak concentrations of PM2.5 in the process of heavy pollution, severe and above average concentrations of PM2.5 pollution, pollution duration, pollution area covered in Beijing research period, The main conclusions as follows:?1? The structure and function of forecasting system: the forecast system not only outputs concentration of major pollutants, but also gives forecast track sources of pollution contribute subregional and regional industries. The system has features and benefits of routine air quality forecasting system, it can also gives the time and space concentration change of major pollutants in Beijing-Tianjin-Hebei region in the next three days. On this basis, with a large number of estimates and by setting the track and sectors, we use the source tracking module of CAMx to achieve forecasting in Beijing-Tianjin-Hebei region.?2? Assessment of wind speed in Forecasting System: a grid resolution of 36 km and 12 km respectively simulate daily average wind speed was no significant difference, but there are some differences with the observed wind speed value. 36 km and 12 km simulation results are high relative to the observed data trends, but there are seasonal variations in the spring, autumn and winter trends but there are better simulate the high trend in summer. The two sets of simulation results has the 99% confidence level test, correlating with a correlation coefficient of 0.91. As ob-servational data is limited, the current comparative analysis is only a preliminary assessment. The differences between wind analog hour and observed values may be greater.?3? Assessment of PM2.5 concentration in Forecasting System: Causing by the discrepancy of source emissions mianly,the difference between 36 km and 12 km of daily mean value simulation PM2.5 is bigger. The PM2.5simulationsof 36 km and 12 km are better able to reproduce the PM2.5observationstrends.The simulation resultof 36 km is better when the air quality rating isexcellent and good, but relatively low in other cases; Thesimulation resultof 12 km simulates high value well, but highly trend at the time of low. The simulation results of 36 km and 12 km have examined the confidence level of 99% was highly correlated, the correlation coefficient is 0.94, this is in part determined by the model system, the numerical differences are mainly caused by source emissions differences.?4? The application of emission reduction measures to influence the process of heavy pollution in Forecasting system: Comparing with no cuts, emission reduction scheme 1 and 2 have cut effect for PM2.5 peak concentration, severe pollution and above average PM2.5 concentrations in the process ofheavy pollution, 12, 11, 10... 4, 3 in advance days to implement emission reduction measures which effect of reducing are same basically,the most significant effect of cutting isone day in advance to take measures to reduce emissions which the cuting amount and percentage is the largest, this is mainly because the primary components of PM2.5 were cut in all cases, the secondary components of PM2.5were increased except the day, and the addition of secondary components of PM2.5weresmaller in one day in advance. The lasting time ofmoderate or above, severe and above in heavy pollution process were cut, the cover of concentration of PM2.5 peak moment in moderate or above, severe and above were cut in the two kinds of schemes and scenes.?5?Forecasting system needs to be optimized: after preliminary examination, the forecast system need to be further optimized and improved. Firstly, combining with observation data and pollution source investigation data,adjust the high and low resolution of source emission inventory to further adjustment and evaluation feedback. Then, collectingcomprehensive observation data and the meteorological factors, conduct a comprehensive assessment for the pollutant results of system simulation. Finally,combining with other model of atmospheric pollutant source analytical and long-term monitoring data, evaluate the regional and industry sources of PM2.5. |
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