Comparison and evaluation of anthropogenic emissions of SO<sub>2</sub> and NO<sub><i>x</i></sub> over China

Abstract

Abstract. Bottom-up emission inventories provide primary understanding of sources of air pollution and essential input of chemical transport models. Focusing on SO 2 and NO x , we conducted a comprehensive evaluation of two widely used anthropogenic emission inventories over China, ECLIPSE and MIX, to explore the potential sources of uncertainties and find clues to improve emission inventories. We first compared the activity rates and emission factors used in two inventories and investigated the reasons of differences and the impacts on emission estimates. We found that SO 2 emission estimates are consistent between two inventories (with 1 % differences), while NO x emissions in ECLIPSE's estimates are 16 % lower than those of MIX. The FGD (flue-gas desulfurization) device penetration rate and removal efficiency, LNB (low-NO x burner) application rate and abatement efficiency in power plants, emission factors of industrial boilers and various vehicle types, and vehicle fleet need further verification. Diesel consumptions are quite uncertain in current inventories. Discrepancies at the sectorial and provincial levels are much higher than those of the national total. We then examined the impacts of different inventories on model performance by using the nested GEOS-Chem model. We finally derived top-down emissions by using the retrieved columns from the Ozone Monitoring Instrument (OMI) compared with the bottom-up estimates. High correlations were observed for SO 2 between model results and OMI columns.For NO x , negative biases in bottom-up gridded emission inventories (−21 % for MIX, −39 % for ECLIPSE) were found compared to the satellite-based emissions. The emission trends from 2005 to 2010 estimated by two inventories were both consistent with satellite observations. The inventories appear to be fit for evaluation of the policies at an aggregated or national level; more work is needed in specific areas in order to improve the accuracy and robustness of outcomes at finer spatial and also technological levels. To our knowledge, this is the first work in which source comparisons detailed to technology-level parameters are made along with the remote sensing retrievals and chemical transport modeling. Through the comparison between bottom-up emission inventories and evaluation with top-down information, we identified potential directions for further improvement in inventory development.

Satellite data reveal a common combustion emission pathway for major cities in China

“…For China, more detailed information on energy use and improved emission inventories is increasingly becoming available for assessment (Li et al, 2017;Zhong et al, 2017). As we also recognize some of the challenges to quantify socioeconomic variables such as the impact of international trade on air pollution (Lin et al, 2014), economic structural upgrading (Mi et al, 2017), greater utilization of renewable energy, and even metrics of performance (Ramaswami et al, 2013), from a physical science perspective, our results strongly support these new developments. We find inconsistencies between the long-term spatiotemporal patterns of emission ratios from RCP8.5 and model predictions of abundance ratios and the corresponding patterns derived from observed enhancement ratios.…”

“…As China grew into the world's second largest economy, its rapid development resulted in substantial emissions (Richter et al, 2005) and more frequent occurrences of severe pollution events in many of its megacities, most notably Beijing (Guo et al, 2014). These affect not only local AQ and public health but are also reported to impact the hemispheric to global atmospheric environment (Lin et al, 2014;Verstraeten et al, 2015). Along with the growth of these cities is a growing body of evidence of decreasing emissions and associated pollution levels in some cities in China.…”

Persistent growth of anthropogenic non-methane volatile organic compound (NMVOC) emissions in China during 1990–2017: drivers, speciation and ozone formation potential

“…Data availability. The detailed emissions data developed in this work and all underlying data presented in figures are available at https://doi.org/10.6084/m9.figshare.c.4544963.v1 (Li et al, 2019).…”

Fine-Scale Columnar and Surface NOx Concentrations over South Korea: Comparison of Surface Monitors, TROPOMI, CMAQ and CAPSS Inventory

“…Indeed, measuring NO 2 vertical column density has been an effective way of monitoring changes in surface anthropogenic NO x emissions globally, including over North America [8][9][10][11], Europe [12][13][14] and Asia [15][16][17][18][19][20]. Recently, comparing satellite-observed NO 2 content with modeled constituents using regional chemistry transport models has become common for evaluating information on the amount of NO x emissions released from anthropogenic sources [15,[21][22][23][24][25].…”