Characteristics and contribution of VOCs emission from motorcycles to ozone formation in Xi’an, China

Surface ozone (O3) pollution, a critical environmental challenge facing government agencies at all levels, is becoming more and more serious in China, especially in rapidly developing urban areas like Beijing. However, in China, few studies have evaluated the contribution of various pollution sources to surface O3, e.g. motor vehicles. In this paper, we combined a non-linear model with an analysis of motor vehicle emissions of NOx and VOCs in an integrated approach to estimate the contribution of motor vehicle emissions to surface O3. The model showed that, in urban areas of Beijing in 2000, the contribution of motor vehicle emissions to surface O3 was 45.9%, and that elimination of 20.0% of motor vehicle emissions will lead to a 7.4% reduction in surface O3, while elimination of 20.0% of NOx or VOC emissions from motor vehicles will result in a 5.0% and 2.5% decline, respectively, in surface O3. In addition, elimination of 10,000 t of NOx from motor vehicles results in the same reduction in surface O3 as elimination of 25,631 t of VOCs. Thus, controlling NOx emissions from motor vehicles is an effective way to control surface O3 pollution in the study area.

The economic losses of vegetation caused by ozone were usually evaluated with existing ozone concentrations. However, in the case a new project is assessed, the marginal losses induced by the additional emissions of ozone’s precursors are required. As ozone is VOC-sensitive in China, this study used novel approaches to assess the marginal economic losses (MELs) for vegetation due to the emission of VOCs as a precursor of ozone, which integrated the geographically constrained AHC algorithm with the spatial regression and applied the cluster-specific coefficients of VOC emissions to the MEL estimation. The new approaches reduce the regression sigma2 from 94.5 to 64.6. The marginal contributions of VOC emissions to ozone concentrations range from 0.123 to 1.180 μg/m3 per kilotonne of emissions per year per 0.25 × 0.25 degree. Negative marginal contributions of NOx emissions were found in Southeast China and the Yunan Guizhou Plateau. County-level marginal increases in AOT40s and MELs due to VOC emissions for crops, semi-natural products, and coniferous and deciduous forests were presented as maps. These values are exceedingly large in Northeast China and the Yunan Guizhou Plateau. Due to the high timber prices, sensitivities to ozone, and long growing seasons, MELs of forests are higher than those of other vegetation types, and thus factories with VOC emissions should be away from the surrounding areas of forests.

Sensitivity analysis of atmospheric oxidation capacity in Beijing based on the GRAPES-CUACE adjoint model

Role of factors controlling diurnal variation of cold-season formaldehyde during Satellite Integrated Joint Monitoring of Air Quality 2021 campaign.

Emerging research indicates that ground-level ozone (O3) has become a leading contributor to air quality concerns in many Chinese cities, with the Yangtze River Delta (YRD) region facing particular challenges. This study investigated the characterization of air pollutants in Wujiang, which is located within the YRD demonstration zone, during the warm season (April–September) of 2022. The contributions of emission and meteorology to O3 were identified, the O3-NOX-VOC sensitivities were discussed, and the VOC sources and their contributions to O3 formation were analyzed. A random forest model revealed that the high O3 concentration was mainly caused by a combination of increased emission intensity due to the resumption of work and production after the COVID-19 pandemic, along with adverse meteorological conditions. The results revealed more than 92% of the pollution days were related to O3 during the warm season, and the impact of O3 precursor emissions was slightly greater than that of the meteorological conditions. O3 formation was in the VOC-limited regime, and emission reduction strategies targeting VOCs, particularly aromatics such as toluene and xylene, have been identified as the most effective approach for mitigating O3 pollution. Changes in O3-NOX-VOC sensitivity were also observed from the VOC-limited regime to the transitional regime, which was primarily driven by variations in the NOX concentrations. The VOC source analysis results showed that the contributions of gasoline vehicle exhaust and diesel engine exhaust (mobile source emissions) were significantly greater than those of the other sources, accounting for 20.8% and 16.5% of the total VOC emissions, respectively. This study highlights the crucial role of mobile source emission control in mitigating O3 pollution. Furthermore, prioritizing the control of VOC emission sources with minimal NOX contributions is highly recommended within the VOC-limited regime.

Mobile source contributions to ambient ozone and particulate matter in 2025

The characteristics and source analysis of VOCs emissions at roadside: Assess the impact of ethanol-gasoline implementation

A WRF-Chem model study of the impact of VOCs emission of a huge petro-chemical industrial zone on the summertime ozone in Beijing, China

Despite significant reductions in fine particulate matter (PM2.5) concentrations in China due to air pollution control measures, ozone (O3) pollution has worsened in recent years, with pronounced regional disparities in long‐term exposure to O3 and NO2. Assessing these disparities in exposure to gaseous pollutants and the resulting unequal health risks between urban and rural regions has become increasingly essential. The contributions of various anthropogenic emissions to O3 and NO2 were quantified using a source‐oriented version of the Community Multiscale Air Quality (CMAQ) model, combined with population and GDP data sets. From 2010 to 2019, NOx and VOC emissions from non‐urban areas decreased by 14% and 25%, respectively, whereas urban anthropogenic activities caused a 10% increase in NOx emissions and a 22% rise in VOC emissions. The simulations indicated that background levels constituted the majority of maximum daily 8‐hr average O3 (MDA8 O3), contributing 83% in 2010 and 75% in 2019. Non‐urban anthropogenic activities were the primary sources of NO2, accounting for 64% in 2010 and 57% in 2019. The proportion of O3 and NO2 from urban anthropogenic emissions in the total concentration continuously increased between 2010 and 2019. Although overall O3‐related premature mortality increased by 51% and NO2‐related premature mortality decreased by 3% during this period, the number of premature mortalities related to O3 and NO2 from urban anthropogenic activities rose by 133% and 15% respectively. We underscore the critical need to prioritize the reduction of urban anthropogenic emissions to effectively mitigate O3 and NO2 pollution in China.

Abstract. Accurate estimates of emissions from natural sources are needed for reliable predictions of ozone and fine particulate matter (PM2.5) using air quality models. In this study, the large-scale atmospheric chemistry transport model, DEHM (the Danish Eulerian Hemispheric Model) is further developed, evaluated and applied to study and quantify the contributions of natural emissions of VOCs, NOx, NH3, SO2, CH4, PM, CO and sea salt to the concentration of ozone and formation of PM2.5 for the year 2006. Natural source categories adopted in the recent model are vegetation, lightning, soils, wild animals and oceans. In this study, the model has been further developed to include more Biogenic Volatile Organic Compounds (BVOCs) and to implement a scheme for secondary organic aerosols as well as an updated description of sea-salt emissions. Our simulations indicate that in the Northern Hemisphere the contribution from natural emissions to the average annual ozone mixing ratios over land is between 4–30 ppbV. Among the natural emissions, BVOCs are found to be the most significant contributors to ozone formation in 2006, enhancing the average ozone mixing ratio by about 11% over the land areas of the Northern Hemisphere. The relative contribution of all the natural emissions to ozone is found to be highest in the northern part of South America by about 42%. Similarly, the highest contribution of all the natural sources to total fine particles over land is found to be in South America by about 74% and sea-salt aerosols demonstrated to play the most important role. However, over the rest of the regions in the model domain the largest contribution from the natural sources to PM2.5 in the specific year 2006 is due to wildfires. The contribution from natural emissions to the mean PM2.5 concentration over the land areas in the model domain is about 34%.

Despite mitigation efforts, ozone pollution in Europe remains a significant issue. As part of the EMEP program, the Task Force on Measurement and Modelling (TFMM) conducted a measurement campaign from 12-19 July 2022 to evaluate the impact of various VOC species on ozone concentration levels and variability. This campaign coincided with adverse thermal conditions – a strong heatwave moving from west to east across Europe, enhancing biogenic VOC emissions and ozone production.To interpret the campaign results, TFMM launched an air quality modelling exercise involving 11 models that reproduced the variability of chemical tracer concentrations in July 2022. Apart from the experiments to reproduce the evolution of concentrations, additional scenarios aimed at assessing the contribution of anthropogenic vs. biogenic VOC emissions were undertaken. The importance of the dry deposition of ozone was also evaluated. We will show preliminary results from the study focusing on model performance during the peak of the episode and the spread between individual models based on measurements taken at EMEP stations and during the campaign. The average contribution of biogenic emissions to ozone and its precursors will also be assessed.

Some extensive numerical simulations of the atmospheric composition fields in Bulgaria have been recently performed. The US EPA Model-3 system was chosen as a modelling tool. The TNO emission inventory was used as emission input. Special pre-processing procedures are created for introducing temporal profiles and speciation of the emissions. The biogenic emissions of VOC are estimated by the model SMOKE. The numerical experiments have been carried out for different emission scenarios, which makes it possible the contribution of emissions from different source categories to be evaluated. The simulations aimed at constructing of ensemble, comprehensive enough as to provide statistically reliable assessment of the atmospheric composition climate of Bulgaria - typical and extreme features of the special/temporal behavior, annual means and seasonal variations, etc. The present one focuses on the results about fine particulate matter. This is a compound with significant impact on human health, so the interest towards it is recently very big.

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation G. K. Gadzhev, K. G. Ganev, M. Prodanov, D. E. Syrakov, N. G. Miloshev, G. J. Georgiev; Some numerically studies of the atmospheric composition climate of Bulgaria. AIP Conf. Proc. 17 October 2013; 1561 (1): 100–111. https://doi.org/10.1063/1.4827219 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioAIP Conference Proceedings Search Advanced Search |Citation Search

Some extensive numerical simulations of the atmospheric composition fields in Bulgaria have been recently performed. The US EPA Model-3 system was chosen as a modelling tool. As the NCEP Global Analysis Data with 1 degree resolution was used as meteorological background, the MM5 and CMAQ nesting capabilities were applied for downscaling the simulations to a 3 km resolution over Bulgaria. The TNO emission inventory was used as emission input. Special pre-processing procedures are created for introducing temporal profiles and speciation of the emissions. The biogenic emissions of VOC are estimated by the model SMOKE. The simulations were carried out for years 2000-2007. The numerical experiments have been carried out for different emission scenarios, which makes it possible the contribution of emissions from different source categories to be evaluated. The Models-3 “Integrated Process Rate Analysis” option is applied to discriminate the role of different dynamic and chemical processes for the air pollution formation. The obtained ensemble of numerical simulation results is extensive enough to allow statistical treatment – calculating not only the mean concentrations and different source categories contribution mean fields, but also standard deviations, skewness, etc. with their dominant temporal modes (seasonal and/or diurnal variations). Thus some basic facts about the atmospheric composition climate of Bulgaria can be retrieved from the simulation ensemble.

Region-wise and state-wise synthesis of vehicular emissions in India and their mitigation due to vehicular emissions standards