With most eastern Chinese cities facing major air quality challenges, there is a strong need for city-scale emission inventories for use in both chemical transport modeling and the development of pollution control policies. In this paper, a high-resolution emission inventory of air pollutants and CO2 for Nanjing, a typical large city in the Yangtze River Delta, is developed incorporating the best available information on local sources. Emission factors and activity data at the unit or facility level are collected and compiled using a thorough onsite survey of major sources. Over 900 individual plants, which account for 97% of the city's total coal consumption, are identified as point sources, and all of the emission-related parameters including combustion technology, fuel quality, and removal efficiency of air pollution control devices (APCD) are analyzed. New data-collection approaches including continuous emission monitoring systems and real-time monitoring of traffic flows are employed to improve spatiotemporal distribution of emissions. Despite fast growth of energy consumption between 2010 and 2012, relatively small inter-annual changes in emissions are found for most air pollutants during this period, attributed mainly to benefits of growing APCD deployment and the comparatively strong and improving regulatory oversight of the large point sources that dominate the levels and spatial distributions of Nanjing emissions overall. The improvement of this city-level emission inventory is indicated by comparisons with observations and other inventories at larger spatial scale. Relatively good spatial correlations are found for SO2, NOX, and CO between the city-scale emission estimates and concentrations at 9 state-opertated monitoring sites (R = 0.58, 0.46, and 0.61, respectively). The emission ratios of specific pollutants including BC to CO, OC to EC, and CO2 to CO compare well to top-down constraints from ground observations. The inter-annual variability and spatial distribution of NOX emissions are consistent with NO2 vertical column density measured by the Ozone Monitoring Instrument (OMI). In particular, the Nanjing city-scale emission inventory correlates better with satellite observations than the downscaled Multi-resolution Emission Inventory for China (MEIC) does when emissions from power plants are excluded. This indicates improvement in emission estimation for sectors other than power generation, notably industry and transportation. High-resolution emission inventory may also provide a basis to consider the quality of instrumental observations. To further improve emission estimation and evaluation, more measurements of both emission factors and ambient levels of given pollutants are suggested; the uncertainties of emission inventories at city scale should also be fully quantified and compared with those at national scale.
Atmospheric Emissions
Advantages of city-scale emission inventory for urban air quality research and policy: the case of Nanjing, a typical industrial city in the Yangtze River Delta, China.” Atmospheric Chemistry and Physics, 15, Pp. 12623-12644. Publisher's VersionAbstract
. 2015. “
Accelerated reduction of SO2 emissions from the US power sector triggered by changing prices of natural gas.” Environmental Science and Technology, 46, 14, Pp. 7882-7889. Publisher's VersionAbstract
. 2012. “Final Manuscript in DASH
This paper is from a series investigating and comparing the prospects for low- and non-carbon power generation in China and the U.S.
Local population exposure to pollutants from the electric power sector.” In Clearing the air: The health and economic damages of air pollution in China, . Cambridge, MA: MIT Press. Publisher's VersionAbstract
. 2007. “
Estimating population exposure to power plant emissions using CALPUFF: A case study in Beijing, China.” Atmospheric Environment, 37, 6, Pp. 815-826. Publisher's VersionAbstract
. 2003. “
An Anthropogenic Emission Inventory of Primary Air Pollutants in China for 2005 and 2010.” In Clearer Skies Over China: Reconciling Air Quality, Climate, and Economic Goals, Pp. 225-261. Cambridge, MA: MIT Press. Publisher's VersionAbstract
. 2013. “
Multiple effects and uncertainties of emission control policies in China: Public health, soil acidification, and global temperature.” Science of the Total Environment , 409, 24, Pp. 5177-5187. Publisher's VersionAbstract
. 2011. “
China's CO2 emissions estimated from the bottom up: Recent trends, spatial distributions, and quantification of uncertainties.” Atmospheric Environment, 59, Pp. 214-223. Publisher's VersionAbstract
. 2012. “Click here to see coverage in United Press International (http://www.upi.com/Science_News/2012/07/06/Estimate-of-China-emission-sa...) and ScienceDaily (http://www.sciencedaily.com/releases/2012/07/120706105419.htm).
Summary for policy.” In Clearing the air: The health and economic damages of air pollution in China, . Cambridge, MA: MIT Press. Publisher's VersionAbstract
. 2007. “
The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants.” Atmospheric Chemistry and Physics, 14, Pp. 8849-8868. Publisher's VersionAbstract
. 2014. “
Understanding China's carbon dioxide emissions from both production and consumption perspectives.” Renewable and Sustainable Energy Reviews, 52, Pp. 189-200. Publisher's VersionAbstract
. 2015. “
Establishment of a database of emission factors for atmospheric pollutant emissions from Chinese coal-fired power plants.” Atmospheric Environment, 44, 12, Pp. 1515-1523. Publisher's VersionAbstract
. 2010. “
The influence of geographic location on population exposure to emissions from power plants throughout China.” Environment International, 32, 3, Pp. 365-373. Publisher's VersionAbstract
. 2006. “
Atmospheric Environment in China: Introduction and Research Review.” In Clearer Skies Over China: Reconciling Air Quality, Climate, and Economic Goals, Pp. 3-58. Cambridge, MA: MIT Press. Publisher's VersionAbstract
. 2013. “
Long-term trend and spatial pattern of PM2.5-induced premature mortality in China.” Environment International, 97, Pp. 180-186. Publisher's VersionAbstract
. 2016. “