This paper aims at constructing an emission source inversion model using a variational processing method and adaptive nudging scheme for the Community Multiscale Air Quality Model (CMAQ) based on satellite data to inv...This paper aims at constructing an emission source inversion model using a variational processing method and adaptive nudging scheme for the Community Multiscale Air Quality Model (CMAQ) based on satellite data to investigate the applicability of high resolution OMI (Ozone Monitoring Instrument) column concentration data for air quality forecasts over the North China. The results show a reasonable consistency and good correlation between the spatial distributions of NO2 from surface and OMI satellite measurements in both winter and summer. Such OMI products may be used to implement integrated variational analysis based on observation data on the ground. With linear and variational corrections made, the spatial distribution of OMI NO2 clearly revealed more localized distributing characteristics of NO2 concentration. With such information, emission sources in the southwest and southeast of North China are found to have greater impacts on air quality in Beijing. When the retrieved emission source inventory based on high-resolution OMI NO2 data was used, the coupled Weather Research Forecasting CMAQ model (WRF-CMAQ) performed significantly better in forecasting NO2 concentration level and its tendency as reflected by the more consistencies between the NO2 concentrations from surface observation and model result. In conclusion, satellite data are particularly important for simulating NO2 concentrations on urban and street-block scale. High-resolution OMI NO2 data are applicable for inversing NOx emission source inventory, assessing the regional pollution status and pollution control strategy, and improving the model forecasting results on urban scale.展开更多
This paper presents a comprehensive observa-tion technique on derived aerosols data from mobile sun-photometer graph and Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) observation. Research results sugges...This paper presents a comprehensive observa-tion technique on derived aerosols data from mobile sun-photometer graph and Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) observation. Research results suggest that after being treated by the variational technique with respect to sunphotometer observations, the Terra- MODIS remote sensing aerosol data are remarkably im-proved, thus for the first time revealing features of the influ-ence of aerosols and pollution emissions of Beijing and its adjoining areas (Hebei, Shandong, etc. provinces). The re-gional impact features of aerosols are related with the pe-ripheral U-shape topography of Beijing. Analyses with Hy-brid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) and meteorological data in the case studied confirm the pollutants diffusion process along the trajectory from the sources in the south-west region, and the regional aerosol impact features.展开更多
The aerosol distribution in Beijing and peripheral cities agglomeration (BPCA) and its re- gional climatic effect are investigated on the basis of the statistical analyses of satellite Total Ozone Map- ping Spectromet...The aerosol distribution in Beijing and peripheral cities agglomeration (BPCA) and its re- gional climatic effect are investigated on the basis of the statistical analyses of satellite Total Ozone Map- ping Spectrometer (TOMS) retrieval aerosol optical depth (AOD) and the meteorological data of sunshine duration, fog days, and low cloud cover, observed at Beijing and its peripheral meteorological stations. The analysis on multi-samples variational correction of the satellite remote sensing Moderate Resolution Imaging Spectroradiometer (MODIS) AOD under the clear sky and stable weather condition in conjunction with surface observations reveal that there was a “triangle-like” distribution pattern of the high values of aerosols in the southern “valley” of the “U-shape” megarelief of Beijing and its peripheral areas. The distribution pattern suggests that the large-scale transfer and diffusion of city agglomeration pollutants might form a relatively persistent characteristic spatial distribution of city agglomeration pollutants much larger than city-scale. Under the background of the particular megarelief effect of Beijing and periph- eral areas, the high value area of TOMS AOD, as well as regional correlation distribution between clear sky sunshine duration and TOMS AOD are also similar to the composite image of MODIS AOD variational fields, that is to say, the effect of atmospheric aerosols was very distinctive in Beijing and peripheral areas. The high value area of the negative correlation between clear sky sunshine duration and TOMS AOD ap-proximately accorded with the significant negative value area of the sunshine duration deviations of the 1980s to the 1990s, and the daily variations of the AOD also showed an anti-phase relation with those of clear sky sunshine duration. The above high cor- relation area of the urban aerosol impact of Beijing- Tianjin region leant towards south peripheral area, with its “center of gravity” in the south of Beijing- Tianjin agglomeration, and the main body of the high correlation area prolongating southwards, forming an aerosol influence domain of “eccentric ellipse” shape, that is to say, there was an aerosol influence domain of some “radius” in Beijing City and its peripheral areas, within and outside which sunshine duration, low cloud cover, and fog days showed a remarkable difference in interannual variation trend. At the downstream of the city agglomeration there was a significant interdecadal increment area of fog or low cloud cover, which might be associated with the local climatic feature of the regional flow convergent field in the diffusion process of city agglomeration pollut- ants in the aerosol influence domain, and such a local dynamical convergence feature might lead to the regional exacerbation of aerosol impact downstream of the city agglomeration. The research result reveals that the significant area of interdecadal change rate of low cloud cover within the aerosol influence do- main is correlated with the regional strengthening effect of aerosol impact of the local wind structure in the “downstream plume area” of the city.展开更多
An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology （ China ） and the National Center for Atmospheric Research （US） in Beijing, October,...An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology （ China ） and the National Center for Atmospheric Research （US） in Beijing, October, 2004. The workshop was intended to share recent progress in urban meteorological research, discuss issues related to research and development priorities faced by diverse Chinese institutions, and explore collaboration opportunities between Chinese and US research institutions. This article summarizes the major issues discussed at the workshop, including observation on urban boundary layer, urban landuse modeling, socio-economic impacts of weather and climates, and air quality in urban environment. It includes recommendations for future urban meteorology observational and modeling research, and potential collaborative opportunities between China and US.展开更多
基金supported by the Ministry of Science and Technology of the People’s Republic of China (Grant No. G1999045700)the China Meteorological Administration Project (Grant No. CMATG2007Z04)
文摘This paper aims at constructing an emission source inversion model using a variational processing method and adaptive nudging scheme for the Community Multiscale Air Quality Model (CMAQ) based on satellite data to investigate the applicability of high resolution OMI (Ozone Monitoring Instrument) column concentration data for air quality forecasts over the North China. The results show a reasonable consistency and good correlation between the spatial distributions of NO2 from surface and OMI satellite measurements in both winter and summer. Such OMI products may be used to implement integrated variational analysis based on observation data on the ground. With linear and variational corrections made, the spatial distribution of OMI NO2 clearly revealed more localized distributing characteristics of NO2 concentration. With such information, emission sources in the southwest and southeast of North China are found to have greater impacts on air quality in Beijing. When the retrieved emission source inventory based on high-resolution OMI NO2 data was used, the coupled Weather Research Forecasting CMAQ model (WRF-CMAQ) performed significantly better in forecasting NO2 concentration level and its tendency as reflected by the more consistencies between the NO2 concentrations from surface observation and model result. In conclusion, satellite data are particularly important for simulating NO2 concentrations on urban and street-block scale. High-resolution OMI NO2 data are applicable for inversing NOx emission source inventory, assessing the regional pollution status and pollution control strategy, and improving the model forecasting results on urban scale.
文摘This paper presents a comprehensive observa-tion technique on derived aerosols data from mobile sun-photometer graph and Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) observation. Research results suggest that after being treated by the variational technique with respect to sunphotometer observations, the Terra- MODIS remote sensing aerosol data are remarkably im-proved, thus for the first time revealing features of the influ-ence of aerosols and pollution emissions of Beijing and its adjoining areas (Hebei, Shandong, etc. provinces). The re-gional impact features of aerosols are related with the pe-ripheral U-shape topography of Beijing. Analyses with Hy-brid Single Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) and meteorological data in the case studied confirm the pollutants diffusion process along the trajectory from the sources in the south-west region, and the regional aerosol impact features.
文摘The aerosol distribution in Beijing and peripheral cities agglomeration (BPCA) and its re- gional climatic effect are investigated on the basis of the statistical analyses of satellite Total Ozone Map- ping Spectrometer (TOMS) retrieval aerosol optical depth (AOD) and the meteorological data of sunshine duration, fog days, and low cloud cover, observed at Beijing and its peripheral meteorological stations. The analysis on multi-samples variational correction of the satellite remote sensing Moderate Resolution Imaging Spectroradiometer (MODIS) AOD under the clear sky and stable weather condition in conjunction with surface observations reveal that there was a “triangle-like” distribution pattern of the high values of aerosols in the southern “valley” of the “U-shape” megarelief of Beijing and its peripheral areas. The distribution pattern suggests that the large-scale transfer and diffusion of city agglomeration pollutants might form a relatively persistent characteristic spatial distribution of city agglomeration pollutants much larger than city-scale. Under the background of the particular megarelief effect of Beijing and periph- eral areas, the high value area of TOMS AOD, as well as regional correlation distribution between clear sky sunshine duration and TOMS AOD are also similar to the composite image of MODIS AOD variational fields, that is to say, the effect of atmospheric aerosols was very distinctive in Beijing and peripheral areas. The high value area of the negative correlation between clear sky sunshine duration and TOMS AOD ap-proximately accorded with the significant negative value area of the sunshine duration deviations of the 1980s to the 1990s, and the daily variations of the AOD also showed an anti-phase relation with those of clear sky sunshine duration. The above high cor- relation area of the urban aerosol impact of Beijing- Tianjin region leant towards south peripheral area, with its “center of gravity” in the south of Beijing- Tianjin agglomeration, and the main body of the high correlation area prolongating southwards, forming an aerosol influence domain of “eccentric ellipse” shape, that is to say, there was an aerosol influence domain of some “radius” in Beijing City and its peripheral areas, within and outside which sunshine duration, low cloud cover, and fog days showed a remarkable difference in interannual variation trend. At the downstream of the city agglomeration there was a significant interdecadal increment area of fog or low cloud cover, which might be associated with the local climatic feature of the regional flow convergent field in the diffusion process of city agglomeration pollut- ants in the aerosol influence domain, and such a local dynamical convergence feature might lead to the regional exacerbation of aerosol impact downstream of the city agglomeration. The research result reveals that the significant area of interdecadal change rate of low cloud cover within the aerosol influence do- main is correlated with the regional strengthening effect of aerosol impact of the local wind structure in the “downstream plume area” of the city.
文摘An international workshop on urban meteorology. observation and modeling, was jointly held by the Institute of Urban Meteorology （ China ） and the National Center for Atmospheric Research （US） in Beijing, October, 2004. The workshop was intended to share recent progress in urban meteorological research, discuss issues related to research and development priorities faced by diverse Chinese institutions, and explore collaboration opportunities between Chinese and US research institutions. This article summarizes the major issues discussed at the workshop, including observation on urban boundary layer, urban landuse modeling, socio-economic impacts of weather and climates, and air quality in urban environment. It includes recommendations for future urban meteorology observational and modeling research, and potential collaborative opportunities between China and US.
