Articles | Volume 10, issue 3
03 Feb 2010
03 Feb 2010
Gaseous elemental mercury depletion events observed at Cape Point during 2007–2008
E.-G. Brunke et al.
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)Evaluating the sensitivity of radical chemistry and ozone formation to ambient VOCs and NOx in BeijingGlobal trends and European emissions of tetrafluoromethane (CF4), hexafluoroethane (C2F6) and octafluoropropane (C3F8)Non-target and suspect characterisation of organic contaminants in ambient air – Part 1: Combining a novel sample clean-up method with comprehensive two-dimensional gas chromatographyLow-NO atmospheric oxidation pathways in a polluted megacitySeasonal variation and origins of volatile organic compounds observed during 2 years at a western Mediterranean remote background site (Ersa, Cape Corsica)Ambient nitro-aromatic compounds – biomass burning versus secondary formation in rural ChinaSecular change in atmospheric Ar∕N2 and its implications for ocean heat uptake and Brewer–Dobson circulationPan-European rural monitoring network shows dominance of NH3 gas and NH4NO3 aerosol in inorganic atmospheric pollution loadMeasurement report: Changing characteristics of atmospheric CH4 in the Tibetan Plateau: records from 1994 to 2019 at the Mount Waliguan stationSoil–atmosphere exchange flux of total gaseous mercury (TGM) at subtropical and temperate forest catchmentsMeasurement report: Long-term variations in carbon monoxide at a background station in China's Yangtze River Delta regionUK surface NO2 levels dropped by 42 % during the COVID-19 lockdown: impact on surface O3Airborne measurements of fire emission factors for African biomass burning sampled during the MOYA campaignSurface–atmosphere fluxes of volatile organic compounds in BeijingElevated levels of OH observed in haze events during wintertime in central BeijingMeasurement report: Important contributions of oxygenated compounds to emissions and chemistry of volatile organic compounds in urban airCharacterisation of African biomass burning plumes and impacts on the atmospheric composition over the south-west Indian OceanMeasurement report: Aircraft observations of ozone, nitrogen oxides, and volatile organic compounds over Hebei Province, ChinaA measurement and model study on ozone characteristics in marine air at a remote island station and its interaction with urban ozone air quality in Shanghai, ChinaMeasurements of higher alkanes using NO+ chemical ionization in PTR-ToF-MS: important contributions of higher alkanes to secondary organic aerosols in ChinaLong-term variations in ozone levels in the troposphere and lower stratosphere over Beijing: observations and model simulationsVariability in gaseous elemental mercury at Villum Research Station, Station Nord, in North Greenland from 1999 to 2017Role of the dew water on the ground surface in HONO distribution: a case measurement in MelpitzEmission of biogenic volatile organic compounds from warm and oligotrophic seawater in the Eastern MediterraneanImpact of the South Asian monsoon outflow on atmospheric hydroperoxides in the upper troposphereNon-methane hydrocarbon (NMHC) fingerprints of major urban and agricultural emission sources for use in source apportionment studiesEstimation of reactive inorganic iodine fluxes in the Indian and Southern Ocean marine boundary layerObservations of atmospheric 14CO2 at Anmyeondo GAW station, South Korea: implications for fossil fuel CO2 and emission ratiosSources of nitrous acid (HONO) in the upper boundary layer and lower free troposphere of the North China Plain: insights from the Mount Tai ObservatoryDecoupling of urban CO2 and air pollutant emission reductions during the European SARS-CoV2 lockdownMeasurement report: Short-term variation in ammonia concentrations in an urban area increased by mist evaporation and emissions from a forest canopy with bird droppingsSpeciation of VOC emissions related to offshore North Sea oil and gas productionSources and sinks driving sulfuric acid concentrations in contrasting environments: implications on proxy calculationsCharacterizing the spatiotemporal nitrogen stable isotopic composition of ammonia in vehicle plumesAssessing contributions of natural surface and anthropogenic emissions to atmospheric mercury in a fast-developing region of eastern China from 2015 to 2018Measurements of carbonyl compounds around the Arabian Peninsula: overview and model comparisonRetrieving tropospheric NO2 vertical column densities around the city of Beijing and estimating NOx emissions based on car MAX-DOAS measurementsMeasurement report: Statistical modelling of long-term trends of atmospheric inorganic gaseous species within proximity of the pollution hotspot in South AfricaGlobal-scale distribution of ozone in the remote troposphere from the ATom and HIPPO airborne field missionsInvestigation of several proxies to estimate sulfuric acid concentration in volcanic plume conditionsAtmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South AfricaPolycyclic aromatic hydrocarbons (PAHs) and oxy- and nitro-PAHs in ambient air of the Arctic town Longyearbyen, SvalbardSource characterization of volatile organic compounds measured by proton-transfer-reaction time-of-flight mass spectrometers in Delhi, IndiaScattered coal is the largest source of ambient volatile organic compounds during the heating season in BeijingNon-target and suspect characterisation of organic contaminants in Arctic air – Part 2: Application of a new tool for identification and prioritisation of chemicals of emerging Arctic concern in airMeasurements of traffic-dominated pollutant emissions in a Chinese megacityReviewing global estimates of surface reactive nitrogen concentration and deposition using satellite retrievalsSource identification of atmospheric organic vapors in two European pine forests: Results from Vocus PTR-TOF observationsAtmospheric reactivity and oxidation capacity during summer at a suburban site between Beijing and TianjinSource apportionment of atmospheric mercury in the remote marine atmosphere: Mace Head GAW station, Irish western coast
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 2125–2147,Short summary
To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2 and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model, which shows that under low NO conditions, there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Daniel Say, Alistair J. Manning, Luke M. Western, Dickon Young, Adam Wisher, Matthew Rigby, Stefan Reimann, Martin K. Vollmer, Michela Maione, Jgor Arduini, Paul B. Krummel, Jens Mühle, Christina M. Harth, Brendan Evans, Ray F. Weiss, Ronald G. Prinn, and Simon O'Doherty
Atmos. Chem. Phys., 21, 2149–2164,Short summary
Perfluorocarbons (PFCs) are potent greenhouse gases with exceedingly long lifetimes. We used atmospheric measurements from a global monitoring network to track the accumulation of these gases in the atmosphere. In the case of the two most abundant PFCs, recent measurements indicate that global emissions are increasing. In Europe, we used a model to estimate regional PFC emissions. Our results show that there was no significant decline in northwest European PFC emissions between 2010 and 2019.
Laura Röhler, Pernilla Bohlin-Nizzetto, Pawel Rostkowski, Roland Kallenborn, and Martin Schlabach
Atmos. Chem. Phys., 21, 1697–1716,Short summary
A novel non-destructive, sulfuric-acid-free clean-up method for high-volume air samples was developed and evaluated with organic chemicals covering a wide range of polarities (logP 2–11). This method, providing quantitative results of comparable quality to traditional methods, was combined with newly developed data treatment strategies for simultaneous suspect and non-target screening. The application to air samples from southern Norway revealed 90 new potential chemicals of emerging concern.
Mike J. Newland, Daniel J. Bryant, Rachel E. Dunmore, Thomas J. Bannan, W. Joe F. Acton, Ben Langford, James R. Hopkins, Freya A. Squires, William Dixon, William S. Drysdale, Peter D. Ivatt, Mathew J. Evans, Peter M. Edwards, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, C. Nicholas Hewitt, James D. Lee, Tianqu Cui, Jason D. Surratt, Xinming Wang, Alastair C. Lewis, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 1613–1625,Short summary
We report the formation of secondary pollutants in the urban megacity of Beijing that are typically associated with remote regions such as rainforests. This is caused by extremely low levels of nitric oxide (NO), typically expected to be high in urban areas, observed in the afternoon. This work has significant implications for how we understand atmospheric chemistry in the urban environment and thus for how to implement effective policies to improve urban air quality.
Cécile Debevec, Stéphane Sauvage, Valérie Gros, Thérèse Salameh, Jean Sciare, François Dulac, and Nadine Locoge
Atmos. Chem. Phys., 21, 1449–1484,Short summary
This study provides a better characterization of the seasonal variations in VOC sources impacting the western Mediterranean region, based on a comprehensive chemical composition measured over 25 months at a representative receptor site (Ersa) and by determining factors controlling their temporal variations. Some insights into dominant drivers for VOC concentration variations in Europe are also provided, built on comparisons of Ersa observations with the concomitant ones of 17 European sites.
Christian Mark Garcia Salvador, Rongzhi Tang, Michael Priestley, Linjie Li, Epameinondas Tsiligiannis, Michael Le Breton, Wenfei Zhu, Limin Zeng, Hui Wang, Ying Yu, Min Hu, Song Guo, and Mattias Hallquist
Atmos. Chem. Phys., 21, 1389–1406,Short summary
High-frequency online measurement of gas- and particle-phase nitro-aromatic compounds (NACs) at a rural site in China, heavily influenced by biomass burning events, enabled the analysis of the production pathway of NACs, including an explanation of strong persistence in the daytime. The contribution of secondary processes was significant, even during the dominant wintertime influence of primary emissions, suggesting the important role of regional secondary chemistry, i.e. photochemical smog.
Shigeyuki Ishidoya, Satoshi Sugawara, Yasunori Tohjima, Daisuke Goto, Kentaro Ishijima, Yosuke Niwa, Nobuyuki Aoki, and Shohei Murayama
Atmos. Chem. Phys., 21, 1357–1373,Short summary
The surface Ar / N2 ratio showed not only secular increasing trends, but also interannual variations in phase with the global ocean heat content (OHC). Sensitivity test by using a two-dimensional model indicated that the secular trend in the Ar / N2 ratio is modified by the gravitational separation in the stratosphere. The analytical results imply that the surface Ar/N2 ratio is an important tracer for detecting spatiotemporally integrated changes in OHC and stratospheric circulation.
Y. Sim Tang, Chris R. Flechard, Ulrich Dämmgen, Sonja Vidic, Vesna Djuricic, Marta Mitosinkova, Hilde T. Uggerud, Maria J. Sanz, Ivan Simmons, Ulrike Dragosits, Eiko Nemitz, Marsailidh Twigg, Netty van Dijk, Yannick Fauvel, Francisco Sanz, Martin Ferm, Cinzia Perrino, Maria Catrambone, David Leaver, Christine F. Braban, J. Neil Cape, Mathew R. Heal, and Mark A. Sutton
Atmos. Chem. Phys., 21, 875–914,Short summary
The DELTA® approach provided speciated, monthly data on reactive gases (NH3, HNO3, SO2, HCl) and aerosols (NH4+, NO3−, SO42−, Cl−, Na+) across Europe (2006–2010). Differences in spatial and temporal concentrations and patterns between geographic regions and four ecosystem types were captured. NH3 and NH4NO3 were dominant components, highlighting their growing relative importance in ecosystem impacts (acidification, eutrophication) and human health effects (NH3 as a precursor to PM2.5) in Europe.
Shuo Liu, Shuangxi Fang, Peng Liu, Miao Liang, Minrui Guo, and Zhaozhong Feng
Atmos. Chem. Phys., 21, 393–413,Short summary
We analyzed 26-year CH4 measurements at Mount Waliguan in the Tibetan Plateau, China. The CH4 increased ~ 133 parts per billion (ppb) with a rate of 5.1 ± 0.1 ppb yr-1 from 1994 to 2019. Major source regions were identified in northeast and southwest. The influence of human activities is more and more serious, and northern India has possibly become a stronger contributor than city regions were in the past. It has become urgent to control CH4 emissions in the Tibetan Plateau.
Jun Zhou, Zhangwei Wang, Xiaoshan Zhang, Charles T. Driscoll, and Che-Jen Lin
Atmos. Chem. Phys., 20, 16117–16133,Short summary
Mercury (Hg) emissions from natural resources have a large uncertainty, which is mainly derived from the forest. A long-term and multiplot (10) study of soil–air fluxes at subtropical and temperate forests was conducted. Forest soils are an important atmospheric Hg source, especially for subtropical forests. The compensation points imply that the atmospheric Hg concentration plays a critical role in inhibiting Hg emissions from the forest floor. Climate change can enhance soil Hg emissions.
Yijing Chen, Qianli Ma, Weili Lin, Xiaobin Xu, Jie Yao, and Wei Gao
Atmos. Chem. Phys., 20, 15969–15982,Short summary
CO is one of the major air pollutants. Our study showed that the long-term CO levels at a background station in one of the most developed areas of China decreased significantly and verified that this downward trend was attributed to the decrease in anthropogenic emissions, which indicated that the adopted pollution control policies were effective. Also, this decrease has an implication for the atmospheric chemistry considering the negative correlation between CO levels and OH radical's lifetime.
James D. Lee, Will S. Drysdale, Doug P. Finch, Shona E. Wilde, and Paul I. Palmer
Atmos. Chem. Phys., 20, 15743–15759,Short summary
Efforts to prevent the COVID-19 virus spreading across the globe have included travel restrictions and the closure of workplaces, leading to a significant drop in emissions of primary air pollutants. This provides for a unique opportunity to examine how air pollutant concentrations respond to an abrupt and prolonged reduction. We examine how NO2 and O3 have been affected at several urban measurement sites in the UK. We look at the change in NO2 compared to previous years and the effect on O3.
Patrick A. Barker, Grant Allen, Martin Gallagher, Joseph R. Pitt, Rebecca E. Fisher, Thomas Bannan, Euan G. Nisbet, Stéphane J.-B. Bauguitte, Dominika Pasternak, Samuel Cliff, Marina B. Schimpf, Archit Mehra, Keith N. Bower, James D. Lee, Hugh Coe, and Carl J. Percival
Atmos. Chem. Phys., 20, 15443–15459,Short summary
Africa is estimated to account for approximately 52 % of global biomass burning (BB) carbon emissions. Despite this, there has been little previous in situ study of African BB emissions. This work presents BB emission factors for various atmospheric trace gases sampled from an aircraft in two distinct areas of Africa (Senegal and Uganda). Intracontinental variability in biomass burning methane emission is identified, which is attributed to difference in the specific fuel mixtures burnt.
W. Joe F. Acton, Zhonghui Huang, Brian Davison, Will S. Drysdale, Pingqing Fu, Michael Hollaway, Ben Langford, James Lee, Yanhui Liu, Stefan Metzger, Neil Mullinger, Eiko Nemitz, Claire E. Reeves, Freya A. Squires, Adam R. Vaughan, Xinming Wang, Zhaoyi Wang, Oliver Wild, Qiang Zhang, Yanli Zhang, and C. Nicholas Hewitt
Atmos. Chem. Phys., 20, 15101–15125,Short summary
Air quality in Beijing is of concern to both policy makers and the general public. In order to address concerns about air quality it is vital that the sources of atmospheric pollutants are understood. This work presents the first top-down measurement of volatile organic compound (VOC) emissions in Beijing. These measurements are used to evaluate the emissions inventory and assess the impact of VOC emission from the city centre on atmospheric chemistry.
Eloise J. Slater, Lisa K. Whalley, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Leigh R. Crilley, Louisa Kramer, William Bloss, Tuan Vu, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 20, 14847–14871,Short summary
The paper details atmospheric chemistry in a megacity (Beijing), focussing on radicals which mediate the formation of secondary pollutants such as ozone and particles. Highly polluted conditions were experienced, including the highest ever levels of nitric oxide (NO), with simultaneous radical measurements. Radical concentrations were large during "haze" events, demonstrating active photochemistry. Modelling showed that our understanding of the chemistry at high NOx levels is incomplete.
Caihong Wu, Chaomin Wang, Sihang Wang, Wenjie Wang, Bin Yuan, Jipeng Qi, Baolin Wang, Hongli Wang, Chen Wang, Wei Song, Xinming Wang, Weiwei Hu, Shengrong Lou, Chenshuo Ye, Yuwen Peng, Zelong Wang, Yibo Huangfu, Yan Xie, Manni Zhu, Junyu Zheng, Xuemei Wang, Bin Jiang, Zhanyi Zhang, and Min Shao
Atmos. Chem. Phys., 20, 14769–14785,Short summary
Based on measurements from an online mass spectrometer, we quantify volatile organic compound (VOC) concentrations from numerous ions of the mass spectrometer, using information from laboratory-obtained calibration results. We find that most VOC concentrations are from oxygenated VOCs (OVOCs). We further show that these OVOCs also contribute significantly to OH reactivity. Our results suggest the important role of OVOCs in VOC emissions and chemistry in urban air.
Bert Verreyken, Crist Amelynck, Jérôme Brioude, Jean-François Müller, Niels Schoon, Nicolas Kumps, Aurélie Colomb, Jean-Marc Metzger, Christopher F. Lee, Theodore K. Koenig, Rainer Volkamer, and Trissevgeni Stavrakou
Atmos. Chem. Phys., 20, 14821–14845,Short summary
Biomass burning (BB) plumes arriving at the Maïdo observatory located in the south-west Indian Ocean during August 2018 and August 2019 are studied using trace gas measurements, Lagrangian transport models and the CAMS near-real-time atmospheric composition service. We investigate (i) secondary production of volatile organic compounds during transport, (ii) efficacy of the CAMS model to reproduce the chemical makeup of BB plumes and (iii) the impact of BB on the remote marine boundary layer.
Sarah E. Benish, Hao He, Xinrong Ren, Sandra J. Roberts, Ross J. Salawitch, Zhanqing Li, Fei Wang, Yuying Wang, Fang Zhang, Min Shao, Sihua Lu, and Russell R. Dickerson
Atmos. Chem. Phys., 20, 14523–14545,Short summary
Airborne observations of ozone and related pollutants show smog was pervasive in spring 2016 over Hebei Province, China. We find high amounts of ozone precursors throughout and even above the PBL, continuing to generate ozone at high rates to be potentially transported downwind. Concentrations even in the rural areas of this highly industrialized province promote widespread ozone production, and we show that to improve air quality over Hebei both NOx and VOCs should be targeted.
Yixuan Gu, Fengxia Yan, Jianming Xu, Yuanhao Qu, Wei Gao, Fangfang He, and Hong Liao
Atmos. Chem. Phys., 20, 14361–14375,Short summary
High levels and statistically insignificant changes of ozone are detected at a remote monitoring site on Sheshan Island in Shanghai, China, from 2012 to 2017; 6-year observations suggest regional transport exerted minimum influence on the offshore oceanic air in September and October. Both city plumes and oceanic air inflows could contribute to ozone enhancements in Shanghai, and the latter are found to lead to 20–30 % increases in urban ozone concentrations based on WRF-Chem simulations.
Chaomin Wang, Bin Yuan, Caihong Wu, Sihang Wang, Jipeng Qi, Baolin Wang, Zelong Wang, Weiwei Hu, Wei Chen, Chenshuo Ye, Wenjie Wang, Yele Sun, Chen Wang, Shan Huang, Wei Song, Xinming Wang, Suxia Yang, Shenyang Zhang, Wanyun Xu, Nan Ma, Zhanyi Zhang, Bin Jiang, Hang Su, Yafang Cheng, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 20, 14123–14138,Short summary
We utilized a novel online mass spectrometry method to measure the total concentration of higher alkanes at each carbon number at two different sites in China, allowing us to take into account SOA contributions from all isomers for higher alkanes. We found that higher alkanes account for significant fractions of SOA formation at the two sites. The contributions are comparable to or even higher than single-ring aromatics, the most-recognized SOA precursors in urban air.
Yuli Zhang, Mengchu Tao, Jinqiang Zhang, Yi Liu, Hongbin Chen, Zhaonan Cai, and Paul Konopka
Atmos. Chem. Phys., 20, 13343–13354,
Henrik Skov, Jens Hjorth, Claus Nordstrøm, Bjarne Jensen, Christel Christoffersen, Maria Bech Poulsen, Jesper Baldtzer Liisberg, David Beddows, Manuel Dall'Osto, and Jesper Heile Christensen
Atmos. Chem. Phys., 20, 13253–13265,Short summary
Mercury is toxic in all its forms. It bioaccumulates in food webs, is ubiquitous in the atmosphere, and atmospheric transport is an important source for this element in the Arctic. Measurements of gaseous elemental mercury have been carried out at the Villum Research Station at Station Nord in northern Greenland since 1999. The measurements are compared with model results from the Danish Eulerian Hemispheric Model. In this way, the dynamics of mercury are investigated.
Yangang Ren, Bastian Stieger, Gerald Spindler, Benoit Grosselin, Abdelwahid Mellouki, Thomas Tuch, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 20, 13069–13089,Short summary
We present HONO measurements from the TROPOS research site in Melpitz, Germany. Investigations of HONO sources and sinks revealed the nighttime formation by heterogeneous conversion of NO2 to HONO followed by a significant surface deposition at night. The evaporation of dew was identified as the main HONO source in the morning. In the following, dew measurements with a self-made dew collector were performed to estimate the amount of evaporated HONO from dew in the atmospheric HONO distribution.
Chen Dayan, Erick Fredj, Pawel K. Misztal, Maor Gabay, Alex B. Guenther, and Eran Tas
Atmos. Chem. Phys., 20, 12741–12759,Short summary
We studied the emission of biogenic volatile organic compounds from both marine and terrestrial ecosystems in the Eastern Mediterranean Basin, a global warming hot spot. We focused on isoprene and dimethyl sulfide (DMS), which are well recognized for their effect on climate and strong impact on photochemical pollution by the former. We found high emissions of isoprene and a strong decadal decrease in the emission of DMS which can both be attributed to the strong increase in seawater temperature.
Bettina Hottmann, Sascha Hafermann, Laura Tomsche, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Marco Neumaier, Andreas Zahn, Birger Bohn, Greta Stratmann, Helmut Ziereis, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 20, 12655–12673,Short summary
During OMO we observed enhanced mixing ratios of hydroperoxides (ROOH) in the Asian monsoon anticyclone (AMA) relative to the background. The observed mixing ratios are higher than steady-state calculations and EMAC simulations, especially in the AMA, indicating atmospheric transport of ROOH. Uncertainties in the scavenging efficiencies likely cause deviations from EMAC. Longitudinal gradients indicate a pool of ROOH towards the center of the AMA associated with upwind convection over India.
Ashish Kumar, Vinayak Sinha, Muhammed Shabin, Haseeb Hakkim, Bernard Bonsang, and Valerie Gros
Atmos. Chem. Phys., 20, 12133–12152,Short summary
Source apportionment studies require information on the chemical fingerprints of pollution sources to correctly quantify source contributions to ambient composition. These chemical fingerprints vary from region to region, depending on fuel composition and combustion conditions, and are poorly constrained over developing regions such as South Asia. This work characterises the chemical fingerprints of urban and agricultural sources using 49 non-methane hydrocarbons and their environmental impacts.
Swaleha Inamdar, Liselotte Tinel, Rosie Chance, Lucy J. Carpenter, Prabhakaran Sabu, Racheal Chacko, Sarat C. Tripathy, Anvita U. Kerkar, Alok K. Sinha, Parli Venkateswaran Bhaskar, Amit Sarkar, Rajdeep Roy, Tomás Sherwen, Carlos Cuevas, Alfonso Saiz-Lopez, Kirpa Ram, and Anoop S. Mahajan
Atmos. Chem. Phys., 20, 12093–12114,Short summary
Iodine chemistry is generating a lot of interest because of its impacts on the oxidising capacity of the marine boundary and depletion of ozone. However, one of the challenges has been predicting the right levels of iodine in the models, which depend on parameterisations for emissions from the sea surface. This paper discusses the different parameterisations available and compares them with observations, showing that our current knowledge is still insufficient, especially on a regional scale.
Haeyoung Lee, Edward J. Dlugokencky, Jocelyn C. Turnbull, Sepyo Lee, Scott J. Lehman, John B. Miller, Gabrielle Pétron, Jeong-Sik Lim, Gang-Woong Lee, Sang-Sam Lee, and Young-San Park
Atmos. Chem. Phys., 20, 12033–12045,Short summary
To understand South Korea's CO2 emissions and sinks as well as those of the surrounding region, we used flask-air samples collected for 2 years at Anmyeondo (36.53° N, 126.32° E; 46 m a.s.l.), South Korea, for analysis of observed 14C in atmospheric CO2 as a tracer of fossil fuel CO2 contribution (Cff). Here, we showed our observation result of 14C and Cff. SF6 and CO can be good proxies of Cff in this study, and the ratio of CO to Cff was compared to a bottom-up inventory.
Ying Jiang, Likun Xue, Rongrong Gu, Mengwei Jia, Yingnan Zhang, Liang Wen, Penggang Zheng, Tianshu Chen, Hongyong Li, Ye Shan, Yong Zhao, Zhaoxin Guo, Yujian Bi, Hengde Liu, Aijun Ding, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 20, 12115–12131,Short summary
We analyzed the characteristics and sources of HONO in the upper boundary layer and lower free troposphere in the North China Plain, based on the field measurements at Mount Tai. Higher-than-expected levels and broad daytime peaks of HONO were observed. Without presence of ground surfaces, aerosol surface plays a key role in the heterogeneous HONO formation at high altitudes. Models without additional HONO sources largely
underestimatedthe oxidation processes in the elevation atmospheres.
Christian Lamprecht, Martin Graus, Marcus Striednig, Michael Stichaner, and Thomas Karl
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The first European SARS-CoV2 wave and associated lockdown provided a unique sensitivity experiment to study air pollution. We find significantly different emission trajectories between classical air pollution and climate gases (e.g. carbon dioxide). The analysis suggests that European policies, shifting residential, public and commercial energy demand towards cleaner combustion, have helped to improve air quality more than expected.
Atmos. Chem. Phys., 20, 11941–11954,Short summary
Various sources and meteorological conditions affect the short-term variation in NH3 concentrations in the urban atmosphere. An analysis of 2 years of hourly data suggests that mist evaporation and stomata exchange of tree leaves after the effects of bird droppings engenders a rapid increase in NH3 concentrations. Emissions from urban tree canopies are a new mode of passing reactive nitrogen that has never before been described as an important source in the literature.
Shona E. Wilde, Pamela A. Dominutti, Stephen J. Andrews, Stephane J.-B. Bauguitte, Ralph R. Burton, Ioana Colfescu, James France, James R. Hopkins, Anna E. Jones, Tom Lachlan-Cope, James D. Lee, Alastair C. Lewis, Stephen D. Mobbs, Alexandra Weiss, Stuart Young, and Ruth M. Purvis
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We use airborne measurements to evaluate the speciation of volatile organic compound (VOC) emissions from offshore oil and gas (O&G) installations in the North Sea. The composition of emissions varied across regions associated with either gas, condensate or oil extraction, demonstrating that VOC emissions are not uniform across the whole O&G sector. We compare our results to VOC source profiles in the UK emissions inventory, showing these emissions are not currently fully characterised.
Lubna Dada, Ilona Ylivinkka, Rima Baalbaki, Chang Li, Yishuo Guo, Chao Yan, Lei Yao, Nina Sarnela, Tuija Jokinen, Kaspar R. Daellenbach, Rujing Yin, Chenjuan Deng, Biwu Chu, Tuomo Nieminen, Yonghong Wang, Zhuohui Lin, Roseline C. Thakur, Jenni Kontkanen, Dominik Stolzenburg, Mikko Sipilä, Tareq Hussein, Pauli Paasonen, Federico Bianchi, Imre Salma, Tamás Weidinger, Michael Pikridas, Jean Sciare, Jingkun Jiang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 20, 11747–11766,Short summary
We rely on sulfuric acid measurements in four contrasting environments, Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; and Beijing, China, representing semi-pristine boreal forest, rural environment in the Mediterranean area, urban environment, and heavily polluted megacity, respectively, in order to define the sources and sinks of sulfuric acid in these environments and to derive a new sulfuric acid proxy to be utilized in locations and during periods when it is not measured.
Wendell W. Walters, Linlin Song, Jiajue Chai, Yunting Fang, Nadia Colombi, and Meredith G. Hastings
Atmos. Chem. Phys., 20, 11551–11567,Short summary
This article details new field observations of the nitrogen stable isotopic composition of ammonia emitted from vehicles conducted in the US and China. Vehicle emissions of ammonia may be a significant source to urban regions with important human health and environmental implications. Our measurements have indicated a consistent isotopic signature from vehicle ammonia emissions. The nitrogen isotopic composition of ammonia may be a useful tool for tracking vehicle emissions.
Xiaofei Qin, Leiming Zhang, Guochen Wang, Xiaohao Wang, Qingyan Fu, Jian Xu, Hao Li, Jia Chen, Qianbiao Zhao, Yanfen Lin, Juntao Huo, Fengwen Wang, Kan Huang, and Congrui Deng
Atmos. Chem. Phys., 20, 10985–10996,Short summary
The uncertainties in mercury emissions are much larger from natural sources than anthropogenic sources. A method was developed to quantify the contributions of natural surface emissions to ambient GEM based on PMF modeling. The annual GEM concentration in eastern China showed a decreasing trend from 2015 to 2018, while the relative contribution of natural surface emissions increased significantly from 41 % in 2015 to 57 % in 2018, gradually surpassing those from anthropogenic sources.
Nijing Wang, Achim Edtbauer, Christof Stönner, Andrea Pozzer, Efstratios Bourtsoukidis, Lisa Ernle, Dirk Dienhart, Bettina Hottmann, Horst Fischer, Jan Schuladen, John N. Crowley, Jean-Daniel Paris, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 10807–10829,Short summary
Carbonyl compounds were measured on a ship travelling around the Arabian Peninsula in summer 2017, crossing both highly polluted and extremely clean regions of the marine boundary layer. We investigated the sources and sinks of carbonyls. The results from a global model showed a significant model underestimation for acetaldehyde, a molecule that can influence regional air chemistry. By adding a diurnal oceanic source, the model estimation was highly improved.
Xinghong Cheng, Jianzhong Ma, Junli Jin, Junrang Guo, Yuelin Liu, Jida Peng, Xiaodan Ma, Minglong Qian, Qiang Xia, and Peng Yan
Atmos. Chem. Phys., 20, 10757–10774,Short summary
We carried out 19 city-circle-around Car MAX-DOAS experiments on the 6th Ring Road of Beijing in Jan, Sep, and Oct 2014. The tropospheric VCDs of NO2 are retrieved and their temporal and spatial distributions are investigated. Then the NOx emission rates in urban Beijing are estimated using the measured NO2 VCDs together with the refined wind fields, NO2-to-NOx ratios, and NO2 lifetimes simulated by the LAPS-WRF-CMAQ model system, and results are compared with the MEIC inventory in 2012.
Jan-Stefan Swartz, Pieter G. van Zyl, Johan P. Beukes, Corinne Galy-Lacaux, Avishkar Ramandh, and Jacobus J. Pienaar
Atmos. Chem. Phys., 20, 10637–10665,Short summary
Statistical modelling of interdependencies between local, regional and global parameters on long-term trends of atmospheric SO2, NO2 and O2 within proximity of the pollution hotspot in South Africa indicated that changes in meteorological conditions and/or variances in source influences contributed to temporal variability. The impact of increased anthropogenic activities and energy demand was evident, while the El Niño–Southern Oscillation made a significant contribution to O3 levels.
Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Kenneth C. Aikin, Teresa Campos, Hannah Clark, Róisín Commane, Bruce Daube, Glenn W. Diskin, James W. Elkins, Ru-Shan Gao, Audrey Gaudel, Eric J. Hintsa, Bryan J. Johnson, Rigel Kivi, Kathryn McKain, Fred L. Moore, David D. Parrish, Richard Querel, Eric Ray, Ricardo Sánchez, Colm Sweeney, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Jacquelyn C. Witte, Steve C. Wofsy, and Thomas B. Ryerson
Atmos. Chem. Phys., 20, 10611–10635,
Clémence Rose, Matti P. Rissanen, Siddharth Iyer, Jonathan Duplissy, Chao Yan, John B. Nowak, Aurélie Colomb, Régis Dupuy, Xu-Cheng He, Janne Lampilahti, Yee Jun Tham, Daniela Wimmer, Jean-Marc Metzger, Pierre Tulet, Jérôme Brioude, Céline Planche, Markku Kulmala, and Karine Sellegri
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Sulfuric acid (H2SO4) is commonly accepted as a key precursor for atmospheric new particle formation. However, direct measurements of [H2SO4] remain challenging, thus motivating the development of proxies. Using data collected in two different volcanic plumes, we show, in these specific conditions, the good performance of a proxy from the literature and highlight as well the benefit of the newly developed proxies for the prediction of the highest [H2SO4] concentrations.
Johannes Bieser, Hélène Angot, Franz Slemr, and Lynwill Martin
Atmos. Chem. Phys., 20, 10427–10439,Short summary
We use numerical models to determine the origin of air masses measured for elemental gaseous mercury (GEM) at Cape Point (CPT), South Africa. Our analysis is based on 10 years of hourly GEM measurements at CPT from 2007 to 2016. Based on GEM concentration and the origin of the air mass, we identify source and sink regions at CPT. We find, that the warm Agulhas Current to the south-east is the major Hg source and the continent the major sink.
Tatiana Drotikova, Aasim M. Ali, Anne Karine Halse, Helena C. Reinardy, and Roland Kallenborn
Atmos. Chem. Phys., 20, 9997–10014,Short summary
Polycyclic aromatic hydrocarbons (PAHs) are not declining in Arctic air despite reductions in global emissions. We studied PAHs and oxy- and nitro-PAHs in gas and particulate phases of Arctic aerosol, collected in autumn 2018 in Longyearbyen, Svalbard. PAHs were found at comparable levels as at other background Scandinavian and European air sampling stations. Statistical analysis confirmed that a coal-fired power plant and vehicle and marine traffic are the main local contributors of PAHs.
Liwei Wang, Jay G. Slowik, Nidhi Tripathi, Deepika Bhattu, Pragati Rai, Varun Kumar, Pawan Vats, Rangu Satish, Urs Baltensperger, Dilip Ganguly, Neeraj Rastogi, Lokesh K. Sahu, Sachchida N. Tripathi, and André S. H. Prévôt
Atmos. Chem. Phys., 20, 9753–9770,
Yuqi Shi, Ziyan Xi, Maimaiti Simayi, Jing Li, and Shaodong Xie
Atmos. Chem. Phys., 20, 9351–9369,Short summary
Beijing had suffered from severe haze pollution prior to the rigorous emission limitations enacted in 2017. We identified scattered coal burning as the largest contributor to ambient volatile organic compounds (VOCs) during the heating season before 2017. The prohibition of scattered coal burning mitigated VOC emissions during winter, but traffic-related sources then became the greatest contributor. However, in other regions, scattered coal burning might still be the key to improve air quality.
Laura Röhler, Martin Schlabach, Peter Haglund, Knut Breivik, Roland Kallenborn, and Pernilla Bohlin-Nizzetto
Atmos. Chem. Phys., 20, 9031–9049,Short summary
A new clean-up method for the SUS and NTS of organic contaminants was applied to high-volume Arctic air samples. A large number of known and new potential organic chemicals of emerging Arctic concern were identified and prioritised with GC×GC-LRMS; 60 % of the identified contaminants (not yet detected in Arctic samples) do not meet currently accepted criteria for LRATP into polar environments. Without our empirical confirmation, they would not be considered potential Arctic contaminants.
Freya A. Squires, Eiko Nemitz, Ben Langford, Oliver Wild, Will S. Drysdale, W. Joe F. Acton, Pingqing Fu, C. Sue B. Grimmond, Jacqueline F. Hamilton, C. Nicholas Hewitt, Michael Hollaway, Simone Kotthaus, James Lee, Stefan Metzger, Natchaya Pingintha-Durden, Marvin Shaw, Adam R. Vaughan, Xinming Wang, Ruili Wu, Qiang Zhang, and Yanli Zhang
Atmos. Chem. Phys., 20, 8737–8761,Short summary
Significant air quality problems exist in megacities like Beijing, China. To manage air pollution, legislators need a clear understanding of pollutant emissions. However, emissions inventories have large uncertainties, and reliable field measurements of pollutant emissions are required to constrain them. This work presents the first measurements of traffic-dominated emissions in Beijing which suggest that inventories overestimate these emissions in the region during both winter and summer.
Lei Liu, Xiuying Zhang, Wen Xu, Xuejun Liu, Xuehe Lu, Jing Wei, Yi Li, Yuyu Yang, Zhen Wang, and Anthony Y. H. Wong
Atmos. Chem. Phys., 20, 8641–8658,Short summary
Excessive atmospheric reactive nitrogen (Nr) deposition can cause a series of negative effects. Thus, it is necessary to accurately estimate Nr deposition to evaluate its impact on the ecosystems and environment. Scientists attempted to estimate surface Nr concentration and deposition using satellite retrievals. We give a thorough review of recent advances in estimating surface Nr concentration and deposition using satellite retrievals of NO2 and NH3 and summarize the existing challenges.
Haiyan Li, Manjula R. Canagaratna, Matthieu Riva, Pekka Rantala, Yanjun Zhang, Steven Thomas, Liine Heikkinen, Pierre-Marie Flaud, Eric Villenave, Emilie Perraudin, Douglas Worsnop, Markku Kulmala, Mikael Ehn, and Federico Bianchi
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
For the first time, we performed binPMF analysis on the complex mass spectra acquired with the Vocus PTR-TOF in two European pine forests and identified various primary emission sources and secondary formation pathways of atmospheric organic vapors, i.e., terpenes and their oxidation products with varying oxidation degrees. This study provides a more comprehensive picture of gas-phase source identifications of organic compounds.
Yuan Yang, Yonghong Wang, Putian Zhou, Dan Yao, Dongsheng Ji, Jie Sun, Yinghong Wang, Shuman Zhao, Wei Huang, Shuanghong Yang, Dean Chen, Wenkang Gao, Zirui Liu, Bo Hu, Renjian Zhang, Limin Zeng, Maofa Ge, Tuukka Petäjä, Veli-Matti Kerminen, Markku Kulmala, and Yuesi Wang
Atmos. Chem. Phys., 20, 8181–8200,
Danilo Custodio, Ralf Ebinghaus, T. Gerard Spain, and Johannes Bieser
Atmos. Chem. Phys., 20, 7929–7939,Short summary
Using a stereo algorithm, we reconstructed 99.9 % of the total atmospheric gas mercury and presented a new insight into atmospheric mercury source assessing, which can have great relevance for policy and regulations in light of the Minamata convention.
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