Atmospheric Environment: X最新文献

{"title":"Methods to quantify particle air pollution removal by urban vegetation: A review","authors":"Irene Vigevani ,&nbsp;Denise Corsini ,&nbsp;Sebastien Comin ,&nbsp;Alessio Fini ,&nbsp;Francesco Ferrini","doi":"10.1016/j.aeaoa.2023.100233","DOIUrl":"10.1016/j.aeaoa.2023.100233","url":null,"abstract":"<div><p>Among the ecosystem services provided by urban forests, the air quality amelioration is particularly relevant. The high level of air pollution in modern cities and the indirect involvement of particulate matter (PM) in the spread of COVID-19 have exacerbated the air quality issue worldwide. However, in the estimation of urban vegetation effectiveness in particle air pollution removal, there is a lack of a standard procedure. Different methods are used for this purpose, making the comparison across different studies difficult. Therefore, there is a need of an extensive review, aimed at: i) identifying the existing direct methods to quantify this ecosystem service, ii) assessing their pros and cons, accuracy and reliability, sustainability, and iii) laying the foundations to create a standard method, commonly and universally recognized. We identified and meticulously assessed five main direct metrics: the gravimetric method (G, 40%), aerosol monitor (AM, 20.5%), wind tunnels and deposition chambers (WT&amp;CH, 19.5%), Scanning Electron Microscopy (SEM, 14%) and Saturation Isothermal Remanent Magnetization (SIRM, 6%). This work provides a crystal picture and a critical framework of the last thirty years literature on this topic and lays the foundations to create a common and shareable approach to quantify the air PM mitigation potential of the urban vegetation. This will be useful to guide researchers and urban planners in shaping greener, healthier, and more sustainable cities.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"21 ","pages":"Article 100233"},"PeriodicalIF":4.6,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590162123000333/pdfft?md5=0dc9f7eed4cca462d9d9e80dfbfa8686&pid=1-s2.0-S2590162123000333-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139189954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"VOC source apportionment: How monitoring characteristics influence positive matrix factorization (PMF) solutions","authors":"Caroline Frischmon,&nbsp;Michael Hannigan","doi":"10.1016/j.aeaoa.2023.100230","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100230","url":null,"abstract":"<div><p>Positive matrix factorization (PMF) can be used to develop more targeted air quality mitigation strategies by identifying major sources of a pollutant in an area. This technique is dependent, however, on the ability of PMF to resolve factors that accurately represent all sources of that pollutant in an area. We investigated how the accuracy of PMF solutions might be influenced by monitoring data characteristics, such as temporal resolution, monitoring location, and species composition, to better inform the use of PMF in VOC mitigation strategies. We applied PMF to five VOC monitoring programs collected within a four-year period in Colorado and found generally consistent factors, which we identified as oil extraction, processing, and evaporation; natural gas; vehicle exhaust; and liquid gasoline/short-lived oil and gas. The main determinant influencing whether or not a dataset resolved each of these sources was whether the dataset had a comprehensive list of VOC species covering key species of each source. Pollution spikes were not well-modeled in any of the solutions. Hyperlocal and volatile chemical product factors expected to be resolved in the industrialized, urban location were also missing, highlighting three limitations of PMF analysis. Wind direction dependence and diurnal trends aided in source identification, suggesting that high-time resolution data is important for developing actionable PMF results. Based on these findings, we recommend that air monitoring for PMF-informed VOC mitigation efforts include high temporal resolution and a comprehensive array of VOC species.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"21 ","pages":"Article 100230"},"PeriodicalIF":4.6,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590162123000308/pdfft?md5=95d511785eed6a3967b420f3ba5806b0&pid=1-s2.0-S2590162123000308-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138633630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Particulate Pb emission factors from wildland fires in the United States","authors":"Amara L. Holder ,&nbsp;Venkatesh Rao ,&nbsp;Kasey Kovalcik ,&nbsp;Larry Virtaranta","doi":"10.1016/j.aeaoa.2023.100229","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100229","url":null,"abstract":"<div><p>Wildland fires, which includes both wild and prescribed fires, and agricultural fires in sum are one of the largest sources of fine particulate matter (PM_2.5) emissions to the atmosphere in the United States (US). Although wildland fire PM_2.5 emissions are primarily composed of carbonaceous material, many other elements including trace metals are emitted at very low levels. Lead (Pb) is a US Environmental Protection Agency (EPA) criteria pollutant that is ubiquitous in the environment at very low concentrations including in biomass that can burn and emit Pb into the atmosphere. Although fires may emit Pb at very low concentrations, they can be a source of sizeable Pb emissions to the atmosphere because of the large quantity of PM_2.5 emitted from fires. In this work, we measure Pb concentrations in unburned biomass, ash/residues, and particulate matter &lt;2.5 μm (PM_2.5) emitted from wildland fires using in-field measurements near prescribed fires and in laboratory simulations. Emission factors were calculated for multiple biomass types, representative of different regions of the US including grasslands in Oregon and Kansas; forest litter from Oregon, Montana, Minnesota, and North Carolina; and peat cores from Minnesota. Most of the biomass Pb remains in the ash/residues. The small percentage (&lt;10%) that is emitted in PM_2.5 is dependent on the biomass Pb concentration. The emissions factors measured here are several orders of magnitude lower than some reported in the literature, but the studies exhibited a wide range of values, which may be due to large uncertainties in the measurement method rather than differences in Pb emissions. Wildland fires are expected to increase in size and frequency in future years and these new emission factors can be used to improve the accuracy of Pb emissions estimates and better constrain our understanding of Pb emissions to the atmosphere.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100229"},"PeriodicalIF":4.6,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590162123000291/pdfft?md5=1d41d155c0c7b10a0b2b1e8bb6e6b636&pid=1-s2.0-S2590162123000291-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134656269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methane emission mapping and quantification in two medium-sized cities in Germany: Heidelberg and Schwetzingen","authors":"Julia B. Wietzel,&nbsp;Martina Schmidt","doi":"10.1016/j.aeaoa.2023.100228","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100228","url":null,"abstract":"<div><p>Estimating the contribution of cities to regional and global methane (CH₄) budgets is challenging due to the complex infrastructures of cities. Mobile measurement devices are well suited to detect CH₄ sources via real-time ambient air measurements. Surveys involving mobile CH₄ measurements were conducted from May 2020 to July 2021 at the street level in two medium-sized cities in Germany. With coverage levels of 30% and 65% of the road networks in Heidelberg and Schwetzingen, respectively, Leak Indications (LIs) for CH₄ were observed with mole fractions of 100 to 9500 ppb above background. A minor portion of leaks (2 out of 70) was attributed to the sewer system, but most leaks originated from the gas distribution network with 0.48 LIs per km obtained in Heidelberg and 0.08 LIs per km determined in Schwetzingen. A method to assign an emission rate to all LIs developed by Weller et al. (2019) was assessed and adapted via controlled CH₄ release experiments in Heidelberg. The method was modified for cities with smaller street widths and smaller distances from the leak to the measurement device. The annual total street-level CH₄ emissions calculated for Heidelberg and Schwetzingen were 42 ± 17 and 1.5 ± 0.5 t CH₄ yr⁻¹ (1sigma), respectively, corresponding to 0.26 ± 0.11 and 0.03 ± 0.01 kg CH₄ yr⁻¹ per capita, respectively.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100228"},"PeriodicalIF":4.6,"publicationDate":"2023-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S259016212300028X/pdfft?md5=2bc2b64a6b769dfac1600fac7a739964&pid=1-s2.0-S259016212300028X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92100638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal assessment of air quality in major cities in Nigeria using satellite data","authors":"Khaled Mahmud ,&nbsp;Bijoy Mitra ,&nbsp;Mohammed Sakib Uddin ,&nbsp;Al-Ekram Elahee Hridoy ,&nbsp;Yusuf A. Aina ,&nbsp;Ismaila Rimi Abubakar ,&nbsp;Syed Masiur Rahman ,&nbsp;Mou Leong Tan ,&nbsp;Muhammad Muhitur Rahman","doi":"10.1016/j.aeaoa.2023.100227","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100227","url":null,"abstract":"<div><p>This study evaluated the concentrations of tropospheric nitrogen dioxide (NO₂), carbon monoxide (CO), ozone (O₃), and Aerosol Index (AI) as well as different meteorological parameters, including atmospheric temperature (AT), relative humidity (RH), and wind speed (WS) in nine Nigerian cities: Aba, Benin, Ibadan, Kaduna, Kano, Lagos, Onitsha, Port Harcourt, and Umuahia. The role of socioeconomic activities on air pollution was also investigated using nighttime light radiance as a surrogate measure. Welch's one-way ANOVA test was performed for the variance study to evaluate the concentration dynamics of the selected tropospheric air pollutants and their association with nighttime light radiance. The mean concentration of CO and AI was highest in Kano, while that of O₃ was the lowest. A similar pattern was also observed in the spatiotemporal transition of the selected pollutants and the nighttime light during the study period. Further, the correlation analysis revealed that AT is positively correlated with NO₂ except in Aba and Benin cities, while it is positively correlated with CO and AI for all cities. The principal component analysis (PCA) revealed that O₃ and RH have strong negative factor loadings, whereas CO, AI, and AT have strong positive factor loadings. This study will guide future researchers by associating the level of pollution with socioeconomic activities, especially during the absence of permanent air quality stations.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100227"},"PeriodicalIF":4.6,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49709970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Atmospheric impact of isoprene-derived Criegee intermediates and isoprene hydroxy hydroperoxide on sulfate aerosol formation in the Asian region","authors":"Hiroo Hata ,&nbsp;Shoma Hoshino ,&nbsp;Michiya Fujita ,&nbsp;Kenichi Tonokura","doi":"10.1016/j.aeaoa.2023.100226","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100226","url":null,"abstract":"<div><p>This study revealed the importance of two isoprene-derived pathways in the formation of sulfate aerosol (SO₄²⁻(p)), which are related to the gas-phase reactions of Criegee intermediates (CIs) and liquid-phase reactions of isoprene hydroxy hydroperoxide (ISOPOOH), in the atmosphere in the Asian region, using the community multiscale air quality (CMAQ) modeling system. The results showed that the incorporation of both isoprene-derived CIs and ISOPOOH chemistry increased the SO₄²⁻(p) concentration in specific domains of Asia, particularly isoprene hotspots, with up to 1% of the total SO₄²⁻(p) concentration compared to that obtained by the basic chemical transport model. The impact of ISOPOOH to SO₄²⁻(p) formation exhibited a more localized pattern compared to that of CIs, attributed to the tendency of ISOPOOH to condense in low-NO regions. SO₄²⁻(p) formation from CIs affected the compositions of nitrate (NO₃⁻), ammonium (NH₄⁺), and secondary organic aerosols (SOA) in the particle phase, and in most of the analyzed sites, those compositions increased from 0.5% to 2.5%. In contrast, SO₄²⁻(p) formation from ISOPOOH exhibits a negative impact on SOA, resulting in a potential reduction of up to 5% due to the loss of SOA precursor by incorporating the ISOPOOH uptake reaction. The sensitivity analysis results showed that most of the SO₄²⁻(p) was generated by the gas-phase reaction of SO₂ with OH; however, the CIs and ISOPOOH also affected the SO₄²⁻(p) formation more than the liquid-phase SO₄²⁻(p) formations by H₂O₂, O₃, O₂, etc.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100226"},"PeriodicalIF":4.6,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49709968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelled atmospheric concentration of tyre wear in an urban environment","authors":"Nina Svensson ,&nbsp;Magnuz Engardt ,&nbsp;Mats Gustafsson ,&nbsp;Yvonne Andersson-Sköld","doi":"10.1016/j.aeaoa.2023.100225","DOIUrl":"https://doi.org/10.1016/j.aeaoa.2023.100225","url":null,"abstract":"<div><p>Microplastics are emitted to the environment from many sources, and transported via water, soil and air. The airborne component is less well studied and measurements often focus on particles larger than 10 μm, while smaller particles are worse from a health perspective and likely more abundant. Measurement studies do often not include tyre wear, which is a large source of microplastics in urban areas. To improve the understanding of the microplastics concentration in urban areas, simulations of emissions and concentrations of atmospheric tyre wear particles (TWP) over Stockholm are performed. The results show that TWP are ubiquitous in urban areas, with highest concentrations along busy highways and in poorly ventilated street canyons. Yearly average roof level concentrations of TWP-PM₁₀ range from 0.2 μg m⁻³ in areas with moderate traffic to 1.2 μg m⁻³ close to busy highways. Average yearly concentrations at three selected street canyons range from 0.7 to 1.1 μg m⁻³. The modelled concentrations correspond to 4–6% of the total measured PM₁₀ concentration. TWP emissions are expected to increase with increasing traffic in future, and possibly also with the increase in vehicle weight with electric vehicles and SUV:s.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100225"},"PeriodicalIF":4.6,"publicationDate":"2023-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49709988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrogen fertilizers technologies as a smart strategy to mitigate nitrous oxide emissions and preserve carbon and nitrogen soil stocks in a coffee crop system","authors":"Leonardo Fernandes Sarkis ,&nbsp;Mateus Portes Dutra ,&nbsp;Camila Almeida dos Santos ,&nbsp;Bruno José Rodrigues Alves ,&nbsp;Segundo Urquiaga ,&nbsp;Douglas Guelfi","doi":"10.1016/j.aeaoa.2023.100224","DOIUrl":"10.1016/j.aeaoa.2023.100224","url":null,"abstract":"<div><p>The paper consolidates the role of conventional and stabilized N fertilizers used in coffee crop production in Brazil and their N₂O emissions in tropical systems. The experiment consisted of the combination of three fertilizers and five doses with four repetitions, totalling 60 experimental plots. The factors of the experiment were conventional urea (U), ammonium nitrate (AN), and urea + NBPT (U_NBPT), while the doses were 0, 150, 275, 400, and 525 kg ha⁻¹ year⁻¹ of N. The municipality is located in a region at 1100 m of altitude, 20°53′26.04″ S and 44°52′04.14″ W. A randomized block design with a 3 × 5 factorial scheme was used. This region, traditional in coffee production, has a tropical humid climate, classified as Cwa according to the Köppen scale, with temperate summer and dry winter. U_NBPT and the ammonium nitrate mitigated the N₂O emissions by 50.6% and 78.5%, respectively, in comparison to the conventional urea. High C stocks were found in the 1 m soil layer, from 117 to 162 t ha⁻¹ of organic C, indicating the importance of the soil as a C sink in coffee plantations. N stocks varied from 33 to 17 t ha⁻¹ of N but no differences among the treatments were found. Approximately 50% of soil C was in the 0–0.4 m layer as a consequence of the greater amount of plant biomass, nutrients, and biological activity. Soil C:N ratio in the entire layer varied from 4.2 to 9.2. Our results indicate that nitrification is the most predominant process of N₂O emissions. The standard EF proposed by the IPCC overestimates the N₂O emissions in the Brazilian coffee plantations and the emissions differ according to the N fertilizer technology. These coffee crop systems have an important ability to stock C and N in the soil.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"20 ","pages":"Article 100224"},"PeriodicalIF":4.6,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46505516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air quality in Tehran, Iran: Spatio-temporal characteristics, human health effects, economic costs and recommendations for good practice","authors":"Amir Hossein Khoshakhlagh ,&nbsp;Mahdiyeh Mohammadzadeh ,&nbsp;Simone Morais","doi":"10.1016/j.aeaoa.2023.100222","DOIUrl":"10.1016/j.aeaoa.2023.100222","url":null,"abstract":"<div><p>Air pollution is one of the most important environmental problems in world cities. The main aims of this study were to characterize the spatio-temporal changes in the concentration of air pollutants in Tehran metropolis, Iran, in the last 6 years, identify the major sources of pollution, estimate the human health effects and economic costs, and recommendations for good practice. Hourly concentrations of standard air pollutants including PM₁₀, PM_2.5, NO₂, SO₂, CO and O₃ were collected from 21 air quality monitoring stations in Tehran from 2016 to 2021 and then, the air quality index (AQI) was calculated monthly and annually. The reached results indicated that AQI is relatively high in Tehran city and is above 100 (unhealthy for sensitive groups/unhealthy) on average on more than 20% (16.99–33.43%) of the days per year. According to the data, the highest and lowest percentages of clean days were observed in 2019 and 2021, respectively, with only 8.49% and 1.10%. Specifically, the highest concentrations of pollutants were observed in the autumn and winter seasons and during the months (by decreasing order) of December, November, and January. The produced annual emission rate of pollutants in Tehran city showed that approximately 84% are due to mobile sources while stationary sources correspond only to about 16%. The economic costs of the effects of air pollution on health were investigated and data showed that cardiovascular diseases &gt; diabetes &gt; lung cancer impose the highest costs to the health care system. Cardiovascular diseases accounted for the largest share of all premature deaths (26.28%) followed by stroke (10.46%), diabetes (3.77%), chronic obstructive pulmonary diseases (COPD) (3.21%), and lung, pharynx and bronchial cancer (2.28%). In addition, the share of air pollution in COPD was 34.2%, which is 31.98–39.2% more than the other ailments under investigation. Implementation of mitigation strategies in Tehran is urgently needed.</p></div>","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"19 ","pages":"Article 100222"},"PeriodicalIF":4.6,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44510498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of natural gas and other hydrocarbons from production sites in northern West Virginia using tracer flux ratio methodology.","authors":"C. Daube, S. Herndon, J. Krechmer, Derek Johnson, Nigel Clark, Tracey L. Footer, E. Thoma","doi":"10.2139/ssrn.4333811","DOIUrl":"https://doi.org/10.2139/ssrn.4333811","url":null,"abstract":"Tracer flux ratio (TFR) methodology performed downwind of 15 active oil and natural gas production sites in Ohio County, West Virginia sought to quantify air pollutant emissions over two weeks in April 2018. In coordination with a production company, sites were randomly selected depending on wind forecasts and nearby road access. Methane (CH4), ethane (C2H6), and tracer gas compounds (acetylene and nitrous oxide) were measured via tunable infrared direct absorption spectroscopy. Ion signals attributed to benzene (C6H6) and other volatile gases (e.g., C7 - C9 aromatics) were measured via proton-transfer reaction time-of-flight mass spectrometry. Short-term whole facility emission rates for 12 sites are reported. Results from TFR were systematically higher than the sum of concurrent on-site full flow sampler measurements, though not all sources were assessed on-site in most cases. In downwind plumes, the mode of the C2H6:CH4 molar ratio distribution for all sites was 0.2, which agreed with spot sample analysis from the site operator. Distribution of C6H6:CH4 ratios was skew but values between 1 and 5 pptv ppbv-1 were common. Additionally, the aromatic profile has been attributed to condensate storage tank emissions. Average ratios of C7 - C9 to C6H6 were similar to other literature values reported for natural gas wells.","PeriodicalId":37150,"journal":{"name":"Atmospheric Environment: X","volume":"19 1","pages":"1-8"},"PeriodicalIF":4.6,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41531484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}