Articles | Volume 14, issue 14
Atmos. Chem. Phys., 14, 7461–7484, 2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Special issue: Atmospheric impacts of Eastern Asia megacities
Research article 22 Jul 2014
Research article | 22 Jul 2014
Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMAs), Korea
H.-K. Kim et al.
No articles found.
Bok H. Baek, Rizzieri Pedruzzi, Minwoo Park, Chi-Tsan Wang, Younha Kim, Chul-Han Song, and Jung-Hun Woo
Geosci. Model Dev. Discuss.,
Preprint under review for GMDShort summary
The Comprehensive Automobile Research System (CARS) is an open-source python-based automobile emissions inventory model designed to efficiently estimate high quality emissions. The CARS is designed to utilize the local vehicle activity database, such as vehicle travel distance, road link-level network information, and vehicle-specific average speed by road type, to generate a temporally and spatially enhanced inventory for policymakers, stakeholders, and the air quality modeling community.
Shixian Zhai, Daniel J. Jacob, Jared F. Brewer, Ke Li, Jonathan M. Moch, Jhoon Kim, Seoyoung Lee, Hyunkwang Lim, Hyun Chul Lee, Su Keun Kuk, Rokjin J. Park, Jaein I. Jeong, Xuan Wang, Pengfei Liu, Gan Luo, Fangqun Yu, Jun Meng, Randall V. Martin, Katherine R. Travis, Johnathan W. Hair, Bruce E. Anderson, Jack E. Dibb, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jung-Hun Woo, Younha Kim, Qiang Zhang, and Hong Liao
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Geostationary satellite aerosol optical depth (AOD) has tremendous potential for monitoring surface fine particulate matter (PM2.5). We integrated data from surface networks, aircraft, and satellites with the GEOS-Chem atmospheric chemistry model to enhance our ability to relate AOD to PM2.5. We attributed 550 nm AOD mainly to secondary aerosols in the planetary boundary layer (PBL) and explained the opposite seasonality between AOD and PM2.5 by seasonality in PBL heights and relative humidity.
Benjamin Gaubert, Louisa K. Emmons, Kevin Raeder, Simone Tilmes, Kazuyuki Miyazaki, Avelino F. Arellano Jr., Nellie Elguindi, Claire Granier, Wenfu Tang, Jérôme Barré, Helen M. Worden, Rebecca R. Buchholz, David P. Edwards, Philipp Franke, Jeffrey L. Anderson, Marielle Saunois, Jason Schroeder, Jung-Hun Woo, Isobel J. Simpson, Donald R. Blake, Simone Meinardi, Paul O. Wennberg, John Crounse, Alex Teng, Michelle Kim, Russell R. Dickerson, Hao He, Xinrong Ren, Sally E. Pusede, and Glenn S. Diskin
Atmos. Chem. Phys., 20, 14617–14647,Short summary
This study investigates carbon monoxide pollution in East Asia during spring using a numerical model, satellite remote sensing, and aircraft measurements. We found an underestimation of emission sources. Correcting the emission bias can improve air quality forecasting of carbon monoxide and other species including ozone. Results also suggest that controlling VOC and CO emissions, in addition to widespread NOx controls, can improve ozone pollution over East Asia.
Baozhu Ge, Syuichi Itahashi, Keiichi Sato, Danhui Xu, Junhua Wang, Fan Fan, Qixin Tan, Joshua S. Fu, Xuemei Wang, Kazuyo Yamaji, Tatsuya Nagashima, Jie Li, Mizuo Kajino, Hong Liao, Meigen Zhang, Zhe Wang, Meng Li, Jung-Hun Woo, Junichi Kurokawa, Yuepeng Pan, Qizhong Wu, Xuejun Liu, and Zifa Wang
Atmos. Chem. Phys., 20, 10587–10610,Short summary
Performances of the simulated deposition for different reduced N (Nr) species in China were conducted with the Model Inter-Comparison Study for Asia. Results showed that simulated wet deposition of oxidized N was overestimated in northeastern China and underestimated in south China, but Nr was underpredicted in all regions by all models. Oxidized N has larger uncertainties than Nr, indicating that the chemical reaction process is one of the most importance factors affecting model performance.
Amir H. Souri, Caroline R. Nowlan, Gonzalo González Abad, Lei Zhu, Donald R. Blake, Alan Fried, Andrew J. Weinheimer, Armin Wisthaler, Jung-Hun Woo, Qiang Zhang, Christopher E. Chan Miller, Xiong Liu, and Kelly Chance
Atmos. Chem. Phys., 20, 9837–9854,Short summary
For the first time, we provide a joint nonlinear optimal estimate of NOx and NMVOC emissions during the KORUS-AQ campaign by simultaneously incorporating SAO's new product of HCHO columns from OMPS and OMI tropospheric NO2 columns into a regional model. Results demonstrate a promising improvement in the performance of the model in terms of HCHO and NO2 concentrations, which in turn enables us to quantify the impact of the emission changes on different pathways of ozone formation and loss.
Arman Pouyaei, Yunsoo Choi, Jia Jung, Bavand Sadeghi, and Chul Han Song
Geosci. Model Dev., 13, 3489–3505,Short summary
This paper introduces a novel Lagrangian model (Concentration Trajectory of Air pollution with an Integrated Lagrangian model, C-TRAIL) for showing the source and receptor areas by following polluted air masses. To investigate the concentrations and trajectories of air masses simultaneously, we use the trajectory-grid (TG) Lagrangian advection model. The TG model follows the concentrations of representative air
packetsof species along trajectories determined by the wind field.
Pablo E. Saide, Meng Gao, Zifeng Lu, Daniel L. Goldberg, David G. Streets, Jung-Hun Woo, Andreas Beyersdorf, Chelsea A. Corr, Kenneth L. Thornhill, Bruce Anderson, Johnathan W. Hair, Amin R. Nehrir, Glenn S. Diskin, Jose L. Jimenez, Benjamin A. Nault, Pedro Campuzano-Jost, Jack Dibb, Eric Heim, Kara D. Lamb, Joshua P. Schwarz, Anne E. Perring, Jhoon Kim, Myungje Choi, Brent Holben, Gabriele Pfister, Alma Hodzic, Gregory R. Carmichael, Louisa Emmons, and James H. Crawford
Atmos. Chem. Phys., 20, 6455–6478,Short summary
Air quality forecasts over the Korean Peninsula captured aerosol optical depth but largely overpredicted surface PM during a Chinese haze transport event. Model deficiency was related to the calculation of optical properties. In order to improve it, aerosol size representation needs to be refined in the calculations, and the representation of aerosol properties, such as size distribution, chemical composition, refractive index, hygroscopicity parameter, and density, needs to be improved.
Sojin Lee, Chul Han Song, Kyung Man Han, Daven K. Henze, Kyunghwa Lee, Jinhyeok Yu, Jung-Hun Woo, Jia Jung, Yunsoo Choi, Pablo E. Saide, and Gregory R. Carmichael
Geosci. Model Dev. Discuss.,
Revised manuscript not accepted
Kyunghwa Lee, Jinhyeok Yu, Sojin Lee, Mieun Park, Hun Hong, Soon Young Park, Myungje Choi, Jhoon Kim, Younha Kim, Jung-Hun Woo, Sang-Woo Kim, and Chul H. Song
Geosci. Model Dev., 13, 1055–1073,Short summary
For the purpose of providing reliable and robust air quality predictions, an operational air quality prediction system was developed for the main air quality criteria species in South Korea (PM10, PM2.5, CO, O3 and SO2) by preparing the initial conditions for model simulations via data assimilation using satellite- and ground-based observations. The performance of the developed air quality prediction system was evaluated using ground in situ data during the KORUS-AQ campaign period.
Meng Gao, Zhiwei Han, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Meng Li, Jung-Hun Woo, Qiang Zhang, Yafang Cheng, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 20, 1147–1161,Short summary
Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative feedbacks. This paper discusses the estimates of aerosol radiative forcing, aerosol feedbacks, and possible causes for the differences among the models.
Hyun S. Kim, Inyoung Park, Chul H. Song, Kyunghwa Lee, Jae W. Yun, Hong K. Kim, Moongu Jeon, Jiwon Lee, and Kyung M. Han
Atmos. Chem. Phys., 19, 12935–12951,Short summary
In this study, a deep recurrent neural network system based on a long short-term memory (LSTM) model was developed for daily PM10 and PM2.5 predictions in South Korea. In general, the accuracies of the LSTM-based predictions were superior to the 3-D CTM-based predictions. Based on this, we concluded that the LSTM-based system could be applied to daily operational PM forecasts in South Korea. We expect that similar AI systems can be applied to the predictions of other atmospheric pollutants.
Daniel L. Goldberg, Pablo E. Saide, Lok N. Lamsal, Benjamin de Foy, Zifeng Lu, Jung-Hun Woo, Younha Kim, Jinseok Kim, Meng Gao, Gregory Carmichael, and David G. Streets
Atmos. Chem. Phys., 19, 1801–1818,Short summary
Using satellite data, we are able to estimate the emissions of NOx (NOx=NO+NO2), a toxic group of air pollutants, in the Seoul metropolitan area. We first develop an enhanced satellite product that better observes NO2 in urban regions. Using this new product, we derive NOx emissions to be twice as large as the emissions reported by the South Korean government. The implication is that the measures taken to reduce NOx emissions in South Korea have not been as effective as regulators have thought.
Benjamin A. Nault, Pedro Campuzano-Jost, Douglas A. Day, Jason C. Schroder, Bruce Anderson, Andreas J. Beyersdorf, Donald R. Blake, William H. Brune, Yonghoon Choi, Chelsea A. Corr, Joost A. de Gouw, Jack Dibb, Joshua P. DiGangi, Glenn S. Diskin, Alan Fried, L. Gregory Huey, Michelle J. Kim, Christoph J. Knote, Kara D. Lamb, Taehyoung Lee, Taehyun Park, Sally E. Pusede, Eric Scheuer, Kenneth L. Thornhill, Jung-Hun Woo, and Jose L. Jimenez
Atmos. Chem. Phys., 18, 17769–17800,Short summary
Aerosol impacts visibility and human health in large cities. Sources of aerosols are still highly uncertain, especially for cities surrounded by numerous other cities. We use observations collected during the Korea–United States Air Quality study to determine sources of organic aerosol (OA). We find that secondary OA (SOA) is rapidly produced over Seoul, South Korea, and that the sources of the SOA originate from short-lived hydrocarbons, which originate from local emissions.
Wenfu Tang, Avelino F. Arellano, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Anna Agustí-Panareda, Mark Parrington, Sebastien Massart, Benjamin Gaubert, Youngjae Lee, Danbi Kim, Jinsang Jung, Jinkyu Hong, Je-Woo Hong, Yugo Kanaya, Mindo Lee, Ryan M. Stauffer, Anne M. Thompson, James H. Flynn, and Jung-Hun Woo
Atmos. Chem. Phys., 18, 11007–11030,
Meng Gao, Zhiwei Han, Zirui Liu, Meng Li, Jinyuan Xin, Zhining Tao, Jiawei Li, Jeong-Eon Kang, Kan Huang, Xinyi Dong, Bingliang Zhuang, Shu Li, Baozhu Ge, Qizhong Wu, Yafang Cheng, Yuesi Wang, Hyo-Jung Lee, Cheol-Hee Kim, Joshua S. Fu, Tijian Wang, Mian Chin, Jung-Hun Woo, Qiang Zhang, Zifa Wang, and Gregory R. Carmichael
Atmos. Chem. Phys., 18, 4859–4884,Short summary
Topic 3 of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase III examines how online coupled air quality models perform in simulating high aerosol pollution in the North China Plain region during wintertime haze events and evaluates the importance of aerosol radiative and microphysical feedbacks. A comprehensive overview of the MICS-ASIA III Topic 3 study design is presented.
Myungje Choi, Jhoon Kim, Jaehwa Lee, Mijin Kim, Young-Je Park, Brent Holben, Thomas F. Eck, Zhengqiang Li, and Chul H. Song
Atmos. Meas. Tech., 11, 385–408,Short summary
This study is a major version upgrade of the aerosol product from GOCI, the first and unique ocean color imager in geostationary earth orbit. It describes the improvement of version 2 of the GOCI Yonsei aerosol retrieval algorithm for near-real-time processing with improved accuracy from the modification of cloud masking, surface reflectance, etc. The product is validated against AERONET/SONET over East Asia with analyses of various errors features, and a pixel-level uncertainty is calculated.
Meng Li, Qiang Zhang, Jun-ichi Kurokawa, Jung-Hun Woo, Kebin He, Zifeng Lu, Toshimasa Ohara, Yu Song, David G. Streets, Gregory R. Carmichael, Yafang Cheng, Chaopeng Hong, Hong Huo, Xujia Jiang, Sicong Kang, Fei Liu, Hang Su, and Bo Zheng
Atmos. Chem. Phys., 17, 935–963,Short summary
An anthropogenic emission inventory for Asia is developed for the years 2008 and 2010 to support the Model Inter-Comparison Study for Asia (MICS-Asia) and the Task Force on Hemispheric Transport of Air Pollution (TF HTAP) projects by a mosaic of up-to-date regional emission inventories. The total Asian emissions in 2010 are estimated as follows: 51.3 Tg SO2, 52.1 Tg NOx, 336.5 Tg CO, 67.0 Tg NMVOC, 28.7 Tg NH3, 31.7 Tg PM10, 22.7 Tg PM2.5, 3.5 Tg BC, 8.3 Tg OC, and 17.3 Pg CO2.
Myungje Choi, Jhoon Kim, Jaehwa Lee, Mijin Kim, Young-Je Park, Ukkyo Jeong, Woogyung Kim, Hyunkee Hong, Brent Holben, Thomas F. Eck, Chul H. Song, Jae-Hyun Lim, and Chang-Keun Song
Atmos. Meas. Tech., 9, 1377–1398,Short summary
The Geostationary Ocean Color Imager (GOCI) is the first ocean color sensor in geostationary orbit. It enables hourly aerosol optical properties to be observed in high spatial resolution. This study presents improvements of the GOCI Yonsei Aerosol Retrieval (YAER) algorithm and its validation results using ground-based and other satellite-based observation products during DRAGON-NE Asia 2012 Campaign. Retrieval errors are also analyzed according to various factors through the validation studies.
S. Lee, C. H. Song, R. S. Park, M. E. Park, K. M. Han, J. Kim, M. Choi, Y. S. Ghim, and J.-H. Woo
Geosci. Model Dev., 9, 17–39,Short summary
We developed an integrated air quality modeling system using AOD data retrieved from a geostationary satellite sensor, GOCI (Geostationary Ocean Color Imager), over Northeast Asia with an application of the spatiotemporal-kriging (STK) method and conducted short-term hindcast runs using the developed system. It appears that the STK approach can greatly reduce not only the errors and biases of AOD and PM10 predictions but also the computational burden of a chemical weather forecast (CWF).
K. M. Han, S. Lee, L. S. Chang, and C. H. Song
Atmos. Chem. Phys., 15, 1913–1938,
S. Seo, J. Kim, H. Lee, U. Jeong, W. Kim, B. N. Holben, S.-W. Kim, C. H. Song, and J. H. Lim
Atmos. Chem. Phys., 15, 319–334,Short summary
The estimation of PM10 from optical measurement of AERONET and MODIS by various empirical models was evaluated for the DRAGON-Asia campaign. The results showed the importance of boundary layer height (BLH) and effective radius (Reff) in estimating PM10. The highest correlation between the estimated and measured values was found to be 0.81 in winter due to the stagnant air mass and low BLH, while the poorest values were 0.54 in spring due to the influence of long-range transport above BLH.
R. J. Park, S. K. Hong, H.-A. Kwon, S. Kim, A. Guenther, J.-H. Woo, and C. P. Loughner
Atmos. Chem. Phys., 14, 7929–7940,
S. X. Wang, B. Zhao, S. Y. Cai, Z. Klimont, C. P. Nielsen, T. Morikawa, J. H. Woo, Y. Kim, X. Fu, J. Y. Xu, J. M. Hao, and K. B. He
Atmos. Chem. Phys., 14, 6571–6603,
R. S. Park, S. Lee, S.-K. Shin, and C. H. Song
Atmos. Chem. Phys., 14, 2185–2201,
M. E. Park, C. H. Song, R. S. Park, J. Lee, J. Kim, S. Lee, J.-H. Woo, G. R. Carmichael, T. F. Eck, B. N. Holben, S.-S. Lee, C. K. Song, and Y. D. Hong
Atmos. Chem. Phys., 14, 659–674,
Related subject area
Subject: Gases | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)Technical note: Quality assessment of ozone reanalysis products and gap-filling over subarctic Europe for vegetation risk mappingEvolution of OH reactivity in NO-free volatile organic compound photooxidation investigated by the fully explicit GECKO-A modelImpact of pyruvic acid photolysis on acetaldehyde and peroxy radical formation in the boreal forest: theoretical calculations and model resultsEvaluating consistency between total column CO2 retrievals from OCO-2 and the in situ network over North America: implications for carbon flux estimationGlobal tropospheric halogen (Cl, Br, I) chemistry and its impact on oxidantsThe role of emission reductions and the meteorological situation for air quality improvements during the COVID-19 lockdown period in central EuropeHeterogeneity and chemical reactivity of the remote troposphere defined by aircraft measurementsA mass-balance-based emission inventory of non-methane volatile organic compounds (NMVOCs) for solvent use in ChinaOpinion: The germicidal effect of ambient air (open-air factor) revisitedImpact of Athabasca oil sands operations on mercury levels in air and depositionStudy of different Carbon Bond 6 (CB6) mechanisms by using a concentration sensitivity analysisAccelerating methane growth rate from 2010 to 2017: leading contributions from the tropics and East AsiaObservation and modelling of ozone-destructive halogen chemistry in a passively degassing volcanic plumeModeling study of the impact of SO2 volcanic passive emissions on the tropospheric sulfur budgetThe impact of organic pollutants from Indonesian peatland fires on the tropospheric and lower stratospheric compositionComprehensive evaluations of diurnal NO2 measurements during DISCOVER-AQ 2011: effects of resolution-dependent representation of NOx emissionsDownscaling system for modeling of atmospheric composition on regional, urban and street scalesSatellite soil moisture data assimilation impacts on modeling weather variables and ozone in the southeastern US – Part 1: An overviewDevelopment of ozone reactivity scales for volatile organic compounds in a Chinese megacityMeasured and modelled air quality trends in Italy over the period 2003–2010Large and increasing methane emissions from eastern Amazonia derived from satellite data, 2010–2018Contrasting chemical environments in summertime for atmospheric ozone across major Chinese industrial regions: the effectiveness of emission control strategiesUnexpected enhancement of ozone exposure and health risks during National Day in ChinaRole of oceanic ozone deposition in explaining temporal variability in surface ozone at High Arctic sitesAtmospheric observations consistent with reported decline in the UK's methane emissions, 2013–2020Oxidation of low-molecular-weight organic compounds in cloud droplets: global impact on tropospheric oxidantsBias-correcting carbon fluxes derived from land-surface satellite data for retrospective and near-real-time assimilation systemsCharacterizing model errors in chemical transport modeling of methane: using GOSAT XCH4 data with weak-constraint four-dimensional variational data assimilationEstimation of fire-induced carbon emissions from Equatorial Asia in 2015 using in situ aircraft and ship observationsInfluence of weather situation on non-CO2 aviation climate effects: the REACT4C climate change functionsInfluence of atmospheric in-cloud aqueous-phase chemistry on global simulation of SO2 in CESM2Impact of international shipping emissions on ozone and PM2.5 in East Asia during summer: the important role of HONO and ClNO2Modelling the impacts of iodine chemistry on the northern Indian Ocean marine boundary layerTime-dependent 3D simulations of tropospheric ozone depletion events in the Arctic spring using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem)Assessing and improving cloud-height-based parameterisations of global lightning flash rate, and their impact on lightning-produced NOx and tropospheric composition in a chemistry–climate modelImpact of regional Northern Hemisphere mid-latitude anthropogenic sulfur dioxide emissions on local and remote tropospheric oxidantsImpact of organic molecular structure on the estimation of atmospherically relevant physicochemical parametersSpatial and temporal variability in the hydroxyl (OH) radical: understanding the role of large-scale climate features and their influence on OH through its dynamical and photochemical driversAnalysis of atmospheric ammonia over South and East Asia based on the MOZART-4 model and its comparison with satellite and surface observationsAir quality and health benefits from ultra-low emission control policy indicated by continuous emission monitoring: a case study in the Yangtze River Delta region, ChinaBackground conditions for an urban greenhouse gas network in the Washington, DC, and Baltimore metropolitan regionExplicit modeling of isoprene chemical processing in polluted air masses in suburban areas of the Yangtze River Delta region: radical cycling and formation of ozone and formaldehydeEvaluation of the LOTOS-EUROS NO2 simulations using ground-based measurements and S5P/TROPOMI observations over GreeceReactive organic carbon emissions from volatile chemical productsA three-dimensional-model inversion of methyl chloroform to constrain the atmospheric oxidative capacityTechnical note: On comparing greenhouse gas emission metricsLate-spring and summertime tropospheric ozone and NO2 in western Siberia and the Russian Arctic: regional model evaluation and sensitivities10-year satellite-constrained fluxes of ammonia improve performance of chemistry transport modelsRevealing the sulfur dioxide emission reductions in China by assimilating surface observations in WRF-ChemTropospheric ozone in CMIP6 simulations
Stefanie Falk, Ane V. Vollsnes, Aud B. Eriksen, Frode Stordal, and Terje Koren Berntsen
Atmos. Chem. Phys., 21, 15647–15661,Short summary
We evaluate regional and global models for ozone modeling and damage risk mapping of vegetation over subarctic Europe. Our analysis suggests that low-resolution global models do not reproduce the observed ozone seasonal cycle at ground level, underestimating ozone by 30–50 %. High-resolution regional models capture the seasonal cycle well, still underestimating ozone by up to 20 %. Our proposed gap-filling method for site observations shows a 76 % accuracy compared to the regional model (80 %).
Zhe Peng, Julia Lee-Taylor, Harald Stark, John J. Orlando, Bernard Aumont, and Jose L. Jimenez
Atmos. Chem. Phys., 21, 14649–14669,Short summary
We use the fully explicit GECKO-A model to study the OH reactivity (OHR) evolution in the NO-free photooxidation of several volatile organic compounds. Oxidation progressively produces more saturated and functionalized species, then breaks them into small species. OHR per C atom evolution is similar for different precursors once saturated multifunctional species are formed. We also find that partitioning of these species to chamber walls leads to large deviations in chambers from the atmosphere.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349,Short summary
We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Bharat Rastogi, John B. Miller, Micheal Trudeau, Arlyn E. Andrews, Lei Hu, Marikate Mountain, Thomas Nehrkorn, Bianca Baier, Kathryn McKain, John Mund, Kaiyu Guan, and Caroline B. Alden
Atmos. Chem. Phys., 21, 14385–14401,Short summary
Predicting Earth's climate is difficult, partly due to uncertainty in forecasting how much CO2 can be removed by oceans and plants, because we cannot measure these exchanges directly on large scales. Satellites such as NASA's OCO-2 can provide part of the needed information, but data need to be highly precise and accurate. We evaluate these data and find small biases in certain months that are similar to the signals of interest. We argue that continued improvement of these data is necessary.
Xuan Wang, Daniel J. Jacob, William Downs, Shuting Zhai, Lei Zhu, Viral Shah, Christopher D. Holmes, Tomás Sherwen, Becky Alexander, Mathew J. Evans, Sebastian D. Eastham, J. Andrew Neuman, Patrick R. Veres, Theodore K. Koenig, Rainer Volkamer, L. Gregory Huey, Thomas J. Bannan, Carl J. Percival, Ben H. Lee, and Joel A. Thornton
Atmos. Chem. Phys., 21, 13973–13996,Short summary
Halogen radicals have a broad range of implications for tropospheric chemistry, air quality, and climate. We present a new mechanistic description and comprehensive simulation of tropospheric halogens in a global 3-D model and compare the model results with surface and aircraft measurements. We find that halogen chemistry decreases the global tropospheric burden of ozone by 11 %, NOx by 6 %, and OH by 4 %.
Volker Matthias, Markus Quante, Jan A. Arndt, Ronny Badeke, Lea Fink, Ronny Petrik, Josefine Feldner, Daniel Schwarzkopf, Eliza-Maria Link, Martin O. P. Ramacher, and Ralf Wedemann
Atmos. Chem. Phys., 21, 13931–13971,Short summary
COVID-19 lockdown measures in spring 2020 led to cleaner air in central Europe. Densely populated areas benefitted mainly from largely reduced NO2 concentrations, while rural areas experienced lower reductions in NO2 but also lower ozone concentrations. Very low particulate matter (PM) concentrations in parts of Europe were not an effect of lockdown measures. Model simulations show that modified weather conditions are more significant for ozone and PM than severe traffic emission reductions.
Hao Guo, Clare M. Flynn, Michael J. Prather, Sarah A. Strode, Stephen D. Steenrod, Louisa Emmons, Forrest Lacey, Jean-Francois Lamarque, Arlene M. Fiore, Gus Correa, Lee T. Murray, Glenn M. Wolfe, Jason M. St. Clair, Michelle Kim, John Crounse, Glenn Diskin, Joshua DiGangi, Bruce C. Daube, Roisin Commane, Kathryn McKain, Jeff Peischl, Thomas B. Ryerson, Chelsea Thompson, Thomas F. Hanisco, Donald Blake, Nicola J. Blake, Eric C. Apel, Rebecca S. Hornbrook, James W. Elkins, Eric J. Hintsa, Fred L. Moore, and Steven Wofsy
Atmos. Chem. Phys., 21, 13729–13746,Short summary
The NASA Atmospheric Tomography (ATom) mission built a climatology of the chemical composition of tropospheric air parcels throughout the middle of the Pacific and Atlantic oceans. The level of detail allows us to reconstruct the photochemical budgets of O3 and CH4 over these vast, remote regions. We find that most of the chemical heterogeneity is captured at the resolution used in current global chemistry models and that the majority of reactivity occurs in the
hottest20 % of parcels.
Ziwei Mo, Ru Cui, Bin Yuan, Huihua Cai, Brian C. McDonald, Meng Li, Junyu Zheng, and Min Shao
Atmos. Chem. Phys., 21, 13655–13666,Short summary
There is a lack of detailed understanding of NMVOC emissions from the use of volatile chemical products (VCPs) in China. This study used a mass balance method to compile a long-term emission inventory for solvent use (including coatings, adhesives, inks, pesticides, cleaners and personal care products) in China during 2000–2017. The striking growth and recent trend of solvent use NMVOC emissions can give important implications for air quality modeling and NMVOC control strategies in China.
R. Anthony Cox, Markus Ammann, John N. Crowley, Paul T. Griffiths, Hartmut Herrmann, Erik H. Hoffmann, Michael E. Jenkin, V. Faye McNeill, Abdelwahid Mellouki, Christopher J. Penkett, Andreas Tilgner, and Timothy J. Wallington
Atmos. Chem. Phys., 21, 13011–13018,Short summary
The term open-air factor was coined in the 1960s, establishing that rural air had powerful germicidal properties possibly resulting from immediate products of the reaction of ozone with alkenes, unsaturated compounds ubiquitously present in natural and polluted environments. We have re-evaluated those early experiments, applying the recently substantially improved knowledge, and put them into the context of the lifetime of aerosol-borne pathogens that are so important in the Covid-19 pandemic.
Ashu Dastoor, Andrei Ryjkov, Gregor Kos, Junhua Zhang, Jane Kirk, Matthew Parsons, and Alexandra Steffen
Atmos. Chem. Phys., 21, 12783–12807,Short summary
An assessment of mercury levels in air and deposition in the Athabasca oil sands region (AOSR) in Northern Alberta, Canada, was conducted to investigate the contribution of Hg emitted from oil sands activities to the surrounding landscape using a 3D process-based Hg model in 2012–2015. Oil sands Hg emissions are found to be important sources of Hg contamination to the local landscape in proximity to the processing activities, particularly in wintertime.
Le Cao, Simeng Li, and Luhang Sun
Atmos. Chem. Phys., 21, 12687–12714,Short summary
Gas-phase chemical reaction mechanisms, e.g., CB6 mechanism, are essential parts of the atmospheric transport model. In order to better understand the changes caused by the updates between different versions of the CB6 mechanism, in this study, the behavior of three different CB6 mechanisms in simulating ozone, nitrogen oxides and formaldehyde under two different emission conditions was analyzed using a concentration sensitivity analysis, and the reasons causing the deviations were figured out.
Yi Yin, Frederic Chevallier, Philippe Ciais, Philippe Bousquet, Marielle Saunois, Bo Zheng, John Worden, A. Anthony Bloom, Robert J. Parker, Daniel J. Jacob, Edward J. Dlugokencky, and Christian Frankenberg
Atmos. Chem. Phys., 21, 12631–12647,Short summary
The growth of methane, the second-most important anthropogenic greenhouse gas after carbon dioxide, has been accelerating in recent years. Using an ensemble of multi-tracer atmospheric inversions constrained by surface or satellite observations, we show that global methane emissions increased by nearly 1 % per year from 2010–2017, with leading contributions from the tropics and East Asia.
Luke Surl, Tjarda Roberts, and Slimane Bekki
Atmos. Chem. Phys., 21, 12413–12441,Short summary
Many different chemical reactions happen when the gases from a volcano mix with air, but what effects do they have? We present aircraft measurements which show that there is less ozone within the plume of Etna than outside it. We have also made a computer model of this chemistry. This model can reproduce the effects seen when halogens (bromine and chlorine) are included in the volcanic emissions. We look closely at the simulation to discover how complicated halogen reactions cause ozone loss.
Claire Lamotte, Jonathan Guth, Virginie Marécal, Martin Cussac, Paul David Hamer, Nicolas Theys, and Philipp Schneider
Atmos. Chem. Phys., 21, 11379–11404,Short summary
Improvements are made in a global chemical transfer model by considering a new volcanic SO2 emissions inventory, with more volcanoes referenced and more information on the altitude of injection. Better constraining volcanic emissions with this inventory improves the global, but mostly local, tropospheric sulfur composition. The tropospheric sulfur budget shows a nonlinearity to the volcanic contribution, especially to the sulfate aerosol burden and sulfur wet deposition.
Simon Rosanka, Bruno Franco, Lieven Clarisse, Pierre-François Coheur, Andrea Pozzer, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 11257–11288,Short summary
The strong El Niño in 2015 led to a particular dry season in Indonesia and favoured severe peatland fires. The smouldering conditions of these fires and the high carbon content of peat resulted in high volatile organic compound (VOC) emissions. By using a comprehensive atmospheric model, we show that these emissions have a significant impact on the tropospheric composition and oxidation capacity. These emissions are transported into to the lower stratosphere, resulting in a depletion of ozone.
Jianfeng Li, Yuhang Wang, Ruixiong Zhang, Charles Smeltzer, Andrew Weinheimer, Jay Herman, K. Folkert Boersma, Edward A. Celarier, Russell W. Long, James J. Szykman, Ruben Delgado, Anne M. Thompson, Travis N. Knepp, Lok N. Lamsal, Scott J. Janz, Matthew G. Kowalewski, Xiong Liu, and Caroline R. Nowlan
Atmos. Chem. Phys., 21, 11133–11160,Short summary
Comprehensive evaluations of simulated diurnal cycles of NO2 and NOy concentrations, vertical profiles, and tropospheric vertical column densities at two different resolutions with various measurements during the DISCOVER-AQ 2011 campaign show potential distribution biases of NOx emissions in the National Emissions Inventory 2011 at both 36 and 4 km resolutions, providing another possible explanation for the overestimation of model results.
Roman Nuterman, Alexander Mahura, Alexander Baklanov, Bjarne Amstrup, and Ashraf Zakey
Atmos. Chem. Phys., 21, 11099–11112,Short summary
The street air pollution is usually higher than the pollution at regional and urban scales. It mostly associated with both local emission sources and urban weather conditions. We present the downscaling system for regional, subregional-urban and street scales and evaluate it for acute air-pollution episode. Its evaluation showed a good prediction score across various spatiotemporal scales as well as feasibility of deterministic modelling approach for the operational street scale forecasting.
Min Huang, James H. Crawford, Joshua P. DiGangi, Gregory R. Carmichael, Kevin W. Bowman, Sujay V. Kumar, and Xiwu Zhan
Atmos. Chem. Phys., 21, 11013–11040,Short summary
This study evaluates the impact of satellite soil moisture data assimilation on modeled weather and ozone fields at various altitudes above the southeastern US during the summer. It emphasizes the importance of soil moisture in the understanding of surface ozone pollution and upper tropospheric chemistry, as well as air pollutants’ source–receptor relationships between the US and its downwind areas.
Yingnan Zhang, Likun Xue, William P. L. Carter, Chenglei Pei, Tianshu Chen, Jiangshan Mu, Yujun Wang, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 21, 11053–11068,Short summary
We developed the localized incremental reactivity (IR) for VOCs in a Chinese megacity and elucidated their applications in calculating the ozone formation potential (OFP). The IR scales showed a strong dependence on chemical mechanisms. Both emission- and observation-based inputs are suitable for the MIR calculation but not the case under mixed-limited or NOx-limited O3 formation regimes. We provide suggestions for the application of IR and OFP scales to aid in VOC control in China.
Ilaria D'Elia, Gino Briganti, Lina Vitali, Antonio Piersanti, Gaia Righini, Massimo D'Isidoro, Andrea Cappelletti, Mihaela Mircea, Mario Adani, Gabriele Zanini, and Luisella Ciancarella
Atmos. Chem. Phys., 21, 10825–10849,Short summary
We present an analysis of modelled trends of PM10, NO2, and O3 airborne concentrations over the Italian territory in 2003–2010. Our analysis shows a general downward simulated trend for all pollutants, with good agreement between observed and modelled values and the model widening both coverage and significance of air concentration trends. Due to the complex atmospheric dynamics, emission reductions do not always result in decreasing concentrations, especially for secondary pollutants.
Chris Wilson, Martyn P. Chipperfield, Manuel Gloor, Robert J. Parker, Hartmut Boesch, Joey McNorton, Luciana V. Gatti, John B. Miller, Luana S. Basso, and Sarah A. Monks
Atmos. Chem. Phys., 21, 10643–10669,Short summary
Methane (CH4) is an important greenhouse gas emitted from wetlands like those found in the basin of the Amazon River. Using an atmospheric model and observations from GOSAT, we quantified CH4 emissions from Amazonia during the previous decade. We found that the largest emissions came from a region in the eastern basin and that emissions there were rising faster than in other areas of South America. This finding was supported by CH4 observations made on aircraft within the basin.
Zhenze Liu, Ruth M. Doherty, Oliver Wild, Michael Hollaway, and Fiona M. O’Connor
Atmos. Chem. Phys., 21, 10689–10706,Short summary
Surface ozone (O3) has become the main cause of atmospheric pollution in the summertime in China since 2013. We find that 70 % reductions in NOx emissions are required to reduce O3 pollution in most of industrial regions of China, and controls in VOC emissions are very important. The new chemical scheme developed for a global chemistry–climate model not only captures the regional air pollution but also benefits the future studies of regional air-quality–climate interactions.
Peng Wang, Juanyong Shen, Men Xia, Shida Sun, Yanli Zhang, Hongliang Zhang, and Xinming Wang
Atmos. Chem. Phys., 21, 10347–10356,Short summary
Ozone (O3) pollution has received extensive attention due to worsening air quality and rising health risks. The Chinese National Day holiday (CNDH), which is associated with intensive commercial and tourist activities, serves as a valuable experiment to evaluate the O3 response during the holiday. We find sharply increasing trends of observed O3 concentrations throughout China during the CNDH, leading to 33 % additional total daily deaths.
Johannes G. M. Barten, Laurens N. Ganzeveld, Gert-Jan Steeneveld, and Maarten C. Krol
Atmos. Chem. Phys., 21, 10229–10248,Short summary
We present an evaluation of ocean and snow/ice O3 deposition in explaining observed hourly surface O3 at 25 pan-Arctic sites using an atmospheric meteorology/chemistry model. The model includes a mechanistic representation of ocean O3 deposition as a function of ocean biogeochemical and mixing conditions. The mechanistic representation agrees better with O3 observations in terms of magnitude and temporal variability especially in the High Arctic (> 70° N).
Mark Lunt, Alistair Manning, Grant Allen, Tim Arnold, Stéphane Bauguitte, Hartmut Boesch, Anita Ganesan, Aoife Grant, Carole Helfter, Eiko Nemitz, Simon O'Doherty, Paul Palmer, Joseph Pitt, Chris Rennick, Daniel Say, Kieran Stanley, Ann Stavert, Dickon Young, and Matt Rigby
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We present an evaluation of the UK's methane emissions between 2013 and 2020 using a network of tall tower measurement sites. We find emissions that are consistent in both magnitude and trend with the UK's reported emissions with a declining trend driven by a decrease in emissions from England. The impact of various components of the modelling setup on these findings are explored through a number of sensitivity studies.
Simon Rosanka, Rolf Sander, Bruno Franco, Catherine Wespes, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 9909–9930,Short summary
In-cloud destruction of ozone depends on hydroperoxyl radicals in cloud droplets, where they are produced by oxygenated volatile organic compound (OVOC) oxygenation. Only rudimentary representations of these processes, if any, are currently available in global atmospheric models. By using a comprehensive atmospheric model that includes a complex in-cloud OVOC oxidation scheme, we show that atmospheric oxidants are reduced and models ignoring this process will underpredict clouds as ozone sinks.
Brad Weir, Lesley E. Ott, George J. Collatz, Stephan R. Kawa, Benjamin Poulter, Abhishek Chatterjee, Tomohiro Oda, and Steven Pawson
Atmos. Chem. Phys., 21, 9609–9628,Short summary
We present a collection of carbon surface fluxes, the Low-order Flux Inversion (LoFI), derived from satellite observations of the Earth's surface and calibrated to match long-term inventories and atmospheric and oceanic records. Simulations using LoFI reproduce background atmospheric carbon dioxide measurements with comparable skill to the leading surface flux products. Available both retrospectively and as a forecast, LoFI enables the study of the carbon cycle as it occurs.
Ilya Stanevich, Dylan B. A. Jones, Kimberly Strong, Martin Keller, Daven K. Henze, Robert J. Parker, Hartmut Boesch, Debra Wunch, Justus Notholt, Christof Petri, Thorsten Warneke, Ralf Sussmann, Matthias Schneider, Frank Hase, Rigel Kivi, Nicholas M. Deutscher, Voltaire A. Velazco, Kaley A. Walker, and Feng Deng
Atmos. Chem. Phys., 21, 9545–9572,Short summary
We explore the utility of a weak-constraint (WC) four-dimensional variational (4D-Var) data assimilation scheme for mitigating systematic errors in methane simulation in the GEOS-Chem model. We use data from the Greenhouse Gases Observing Satellite (GOSAT) and show that, compared to the traditional 4D-Var approach, the WC scheme improves the agreement between the model and independent observations. We find that the WC corrections to the model provide insight into the source of the errors.
Yosuke Niwa, Yousuke Sawa, Hideki Nara, Toshinobu Machida, Hidekazu Matsueda, Taku Umezawa, Akihiko Ito, Shin-Ichiro Nakaoka, Hiroshi Tanimoto, and Yasunori Tohjima
Atmos. Chem. Phys., 21, 9455–9473,Short summary
Fires in Equatorial Asia release a large amount of carbon into the atmosphere. Extensively using high-precision atmospheric carbon dioxide (CO2) data from a commercial aircraft observation project, we estimated fire carbon emissions in Equatorial Asia induced by the big El Niño event in 2015. Additional shipboard measurement data elucidated the validity of the analysis and the best estimate indicated 273 Tg C for fire emissions during September–October 2015.
Christine Frömming, Volker Grewe, Sabine Brinkop, Patrick Jöckel, Amund S. Haslerud, Simon Rosanka, Jesper van Manen, and Sigrun Matthes
Atmos. Chem. Phys., 21, 9151–9172,Short summary
The influence of weather situations on non-CO2 aviation climate impact is investigated to identify systematic weather-related sensitivities. If aircraft avoid the most sensitive areas, climate impact might be reduced. Enhanced significance is found for emission in relation to high-pressure systems, jet stream, polar night, and tropopause altitude. The results represent a comprehensive data set for studies aiming at weather-dependent flight trajectory optimization to reduce total climate impact.
Wendong Ge, Junfeng Liu, Kan Yi, Jiayu Xu, Yizhou Zhang, Xiurong Hu, Jianmin Ma, Xuejun Wang, Yi Wan, Jianying Hu, Zhaobin Zhang, Xilong Wang, and Shu Tao
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Compared with the observations, the results incorporating detailed aqueous-phase chemistry greatly reduced SO2 overestimation. The biases in annual simulated SO2 concentrations decreased by 46 %, 41 %, and 22 % in Europe, the United States and China, respectively. Fe-chemistry and HOx-chemistry contributed more to SO2 oxidation than N-chemistry. Higher concentrations of soluble Fe and higher pH values could further enhance the oxidation capacity.
Jianing Dai and Tao Wang
Atmos. Chem. Phys., 21, 8747–8759,Short summary
We used the WRF–Chem model with the latest HONO and ClNO2 processes to investigate their effects on the concentrations of ROx radicals, O3, and PM2.5 in Asia during summer. The results show that the ship-derived HONO and ClNO2 increased the ROx radical concentration by 2–3 times and subsequently increased the O3 and PM2.5 concentrations in marine areas. These findings indicate the importance of these nitrogen processes in the evaluation of the impact of ship emissions on air quality.
Anoop S. Mahajan, Qinyi Li, Swaleha Inamdar, Kirpa Ram, Alba Badia, and Alfonso Saiz-Lopez
Atmos. Chem. Phys., 21, 8437–8454,Short summary
Using a regional model, we show that iodine-catalysed reactions cause large regional changes in the chemical composition in the northern Indian Ocean, with peak changes of up to 25 % in O3, 50 % in nitrogen oxides (NO and NO2), 15 % in hydroxyl radicals (OH), 25 % in hydroperoxyl radicals (HO2), and up to a 50 % change in the nitrate radical (NO3). These results show the importance of including iodine chemistry in modelling the atmosphere in this region.
Maximilian Herrmann, Holger Sihler, Udo Frieß, Thomas Wagner, Ulrich Platt, and Eva Gutheil
Atmos. Chem. Phys., 21, 7611–7638,Short summary
Time-dependent 3D numerical simulations of tropospheric bromine release and ozone depletion events (ODEs) in the Arctic polar spring of 2009 are compared to observations. Simulation results agree well with the observations at both Utqiaġvik, Alaska, and at Summit, Greenland. In a parameter study, different settings for the bromine release mechanism are evaluated. An enhancement of the bromine release mechanism improves the agreement regarding the occurrence of ODEs with the observations.
Ashok K. Luhar, Ian E. Galbally, Matthew T. Woodhouse, and Nathan Luke Abraham
Atmos. Chem. Phys., 21, 7053–7082,Short summary
Lightning-generated nitrogen oxides (LNOx) greatly influence tropospheric photochemistry. The most common parameterisation of lightning flash rate used to calculate LNOx in global composition models underestimates measurements over the ocean by a factor of 20–25. We formulate and validate an alternative parameterisation to remedy this problem. The new scheme causes an increase in the ozone burden by 8.5 % and the hydroxyl radical by 13 %, and these have implications for climate and air quality.
Daniel M. Westervelt, Arlene M. Fiore, Colleen B. Baublitz, and Gustavo Correa
Atmos. Chem. Phys., 21, 6799–6810,Short summary
Particulate air pollution in the atmosphere can impact the availability of gas-phase chemical constituents, which can then have feedbacks on gas-phase air pollutants. We use a chemistry–climate computer model to simulate the impact of particulate pollution from three major world regions on gas-phase chemical constituents. We find that surface-level ozone air pollution decreases by up to 5 ppbv over China in response to Chinese particulate air pollution, which has implications for policy.
Gabriel Isaacman-VanWertz and Bernard Aumont
Atmos. Chem. Phys., 21, 6541–6563,Short summary
There are tens of thousands of different chemical compounds in the atmosphere. To tackle this complexity, there are a wide range of different methods to estimate their physical and chemical properties. We use these methods to understand how much the detailed structure of a molecule impacts its properties, and the extent to which properties can be estimated without knowing this level of detail. We find that structure matters, but methods lacking that level of detail still perform reasonably well.
Daniel C. Anderson, Bryan N. Duncan, Arlene M. Fiore, Colleen B. Baublitz, Melanie B. Follette-Cook, Julie M. Nicely, and Glenn M. Wolfe
Atmos. Chem. Phys., 21, 6481–6508,Short summary
We demonstrate that large-scale climate features are the primary driver of year-to-year variability in simulated values of the hydroxyl radical, the primary atmospheric oxidant, over 1980–2018. The El Niño–Southern Oscillation is the dominant mode of hydroxyl variability, resulting in large-scale global decreases in OH during El Niño events. Other climate modes, such as the Australian monsoon and the North Atlantic Oscillation, have impacts of similar magnitude but on on more localized scales.
Pooja V. Pawar, Sachin D. Ghude, Chinmay Jena, Andrea Móring, Mark A. Sutton, Santosh Kulkarni, Deen Mani Lal, Divya Surendran, Martin Van Damme, Lieven Clarisse, Pierre-François Coheur, Xuejun Liu, Gaurav Govardhan, Wen Xu, Jize Jiang, and Tapan Kumar Adhya
Atmos. Chem. Phys., 21, 6389–6409,Short summary
In this study, simulations of atmospheric ammonia (NH3) with MOZART-4 and HTAP-v2 are compared with satellite (IASI) and ground-based measurements to understand the spatial and temporal variability of NH3 over two emission hotspot regions of Asia, the IGP and the NCP. Our simulations indicate that the formation of ammonium aerosols is quicker over the NCP than the IGP, leading to smaller NH3 columns over the higher NH3-emitting NCP compared to the IGP region for comparable emissions.
Yan Zhang, Yu Zhao, Meng Gao, Xin Bo, and Chris P. Nielsen
Atmos. Chem. Phys., 21, 6411–6430,Short summary
We combined air quality and exposure response models to analyze the benefits for air quality and human health of China’s ultra-low emission policy in one of its most developed regions. Atmospheric observations and the air quality model were also used to demonstrate improvement of emission inventories incorporating online emission monitoring data. With implementation of the policy in both power and industrial sectors, the attributable deaths due to PM2.5 exposure are estimated to decrease 5.5 %.
Anna Karion, Israel Lopez-Coto, Sharon M. Gourdji, Kimberly Mueller, Subhomoy Ghosh, William Callahan, Michael Stock, Elizabeth DiGangi, Steve Prinzivalli, and James Whetstone
Atmos. Chem. Phys., 21, 6257–6273,Short summary
Estimating city emissions based on atmospheric observations requires that the portion of observed greenhouse gases that originated in the city be separated from the portion that originated outside the city, also known as the background concentration. Here, we investigate different methods to determine background concentrations for the Washington, DC, and Baltimore, MD, region and evaluate how well those methods work and the uncertainties they involve.
Kun Zhang, Ling Huang, Qing Li, Juntao Huo, Yusen Duan, Yuhang Wang, Elly Yaluk, Yangjun Wang, Qingyan Fu, and Li Li
Atmos. Chem. Phys., 21, 5905–5917,Short summary
Recently, high O3 concentrations were frequently observed in rural areas of the Yangtze River Delta (YRD) region under stagnant conditions. Using an online measurement and observation-based model, we investigated the budget of ROx radicals and the influence of isoprene chemistry on O3 formation. Our results underline that isoprene chemistry in the rural atmosphere becomes important with the participation of anthropogenic NOx.
Ioanna Skoulidou, Maria-Elissavet Koukouli, Astrid Manders, Arjo Segers, Dimitris Karagkiozidis, Myrto Gratsea, Dimitris Balis, Alkiviadis Bais, Evangelos Gerasopoulos, Trisevgeni Stavrakou, Jos van Geffen, Henk Eskes, and Andreas Richter
Atmos. Chem. Phys., 21, 5269–5288,Short summary
The performance of LOTOS-EUROS v2.2.001 regional chemical transport model NO2 simulations is investigated over Greece from June to December 2018. Comparison with in situ NO2 measurements shows a spatial correlation coefficient of 0.86, while the model underestimates the concentrations mostly during daytime (12 to 15:00 local time). Further, the simulated tropospheric NO2 columns are evaluated against ground-based MAX-DOAS NO2 measurements and S5P/TROPOMI observations for July and December 2018.
Karl M. Seltzer, Elyse Pennington, Venkatesh Rao, Benjamin N. Murphy, Madeleine Strum, Kristin K. Isaacs, and Havala O. T. Pye
Atmos. Chem. Phys., 21, 5079–5100,Short summary
Volatile chemical products (VCPs) are an increasingly important source of anthropogenic reactive organic carbon emissions. Here, we develop VCPy, a new framework to model organic emissions from VCPs throughout the United States. At the national-level, VCPy emissions are broadly consistent with the US EPA’s 2017 National Emission Inventory, however county-level and categorical estimates can differ substantially. An observational evaluation indicates high fidelity in the methods employed here.
Stijn Naus, Stephen A. Montzka, Prabir K. Patra, and Maarten C. Krol
Atmos. Chem. Phys., 21, 4809–4824,Short summary
Following up on previous box model studies, we employ a 3D transport model to estimate variations in the hydroxyl radical (OH) from observations of methyl chloroform (MCF). We derive small interannual OH variations that are consistent with variations in the El Niño–Southern Oscillation. We also find evidence for the release of MCF from oceans in atmospheric gradients of MCF. Both findings highlight the added value of a 3D transport model since box model studies did not identify these effects.
Ian Enting and Nathan Clisby
Atmos. Chem. Phys., 21, 4699–4708,Short summary
We provide a new framework for comparing short-lived greenhouse gases to long-lived greenhouse gases such as carbon dioxide using methane as an example. This can clarify the differences between various proposals that have been introduced in order to overcome the use of global warming potentials as a measure of greenhouse gas equivalence.
Thomas Thorp, Stephen R. Arnold, Richard J. Pope, Dominick V. Spracklen, Luke Conibear, Christoph Knote, Mikhail Arshinov, Boris Belan, Eija Asmi, Tuomas Laurila, Andrei I. Skorokhod, Tuomo Nieminen, and Tuukka Petäjä
Atmos. Chem. Phys., 21, 4677–4697,Short summary
We compare modelled near-surface pollutants with surface and satellite observations to better understand the controls on the regional concentrations of pollution in western Siberia for late spring and summer in 2011. We find two commonly used emission inventories underestimate human emissions when compared to observations. Transport emissions are the main source of pollutants within the region during this period, whilst fire emissions peak during June and are only significant south of 60° N.
Nikolaos Evangeliou, Yves Balkanski, Sabine Eckhardt, Anne Cozic, Martin Van Damme, Pierre-François Coheur, Lieven Clarisse, Mark W. Shephard, Karen E. Cady-Pereira, and Didier Hauglustaine
Atmos. Chem. Phys., 21, 4431–4451,Short summary
Ammonia, a substance that has played a key role in sustaining life, has been increasing in the atmosphere, affecting climate and humans. Understanding the reasons for this increase is important for the beneficial use of ammonia. The evolution of satellite products gives us the opportunity to calculate ammonia emissions easier. We calculated global ammonia emissions over the last 10 years, incorporated them into a chemistry model and recorded notable improvement in reproducing observations.
Tie Dai, Yueming Cheng, Daisuke Goto, Yingruo Li, Xiao Tang, Guangyu Shi, and Teruyuki Nakajima
Atmos. Chem. Phys., 21, 4357–4379,Short summary
The anthropogenic emission of sulfur dioxide (SO2) over China has significantly declined as a consequence of the clean air actions. We have developed a new emission inversion system to dynamically update the SO2 emission grid by grid over China by assimilating ground-based SO2 observations. The inverted SO2 emission over China in November 2016 on average had declined by 49.4 % since 2010, which is well in agreement with the bottom-up estimation of 48.0 %.
Paul T. Griffiths, Lee T. Murray, Guang Zeng, Youngsub Matthew Shin, N. Luke Abraham, Alexander T. Archibald, Makoto Deushi, Louisa K. Emmons, Ian E. Galbally, Birgit Hassler, Larry W. Horowitz, James Keeble, Jane Liu, Omid Moeini, Vaishali Naik, Fiona M. O'Connor, Naga Oshima, David Tarasick, Simone Tilmes, Steven T. Turnock, Oliver Wild, Paul J. Young, and Prodromos Zanis
Atmos. Chem. Phys., 21, 4187–4218,Short summary
We analyse the CMIP6 Historical and future simulations for tropospheric ozone, a species which is important for many aspects of atmospheric chemistry. We show that the current generation of models agrees well with observations, being particularly successful in capturing trends in surface ozone and its vertical distribution in the troposphere. We analyse the factors that control ozone and show that they evolve over the period of the CMIP6 experiments.
Akaike, H.: Information theory and an extension of the maximum likelihood principle. In: International symposium on information theory, 2nd, Tsahkadsor, Armenian SS, Budapest: Akademiai Kiado, 267–281, 1973.
Arneth, A., Schurgers, G., Lathiere, J., Duhl, T., Beerling, D. J., Hewitt, C. N., Martin, M., and Guenther, A.: Global terrestrial isoprene emission models: sensitivity to variability in climate and vegetation, Atmos. Chem. Phys., 11, 8037–8052, https://doi.org/10.5194/acp-11-8037-2011, 2011.
Atkinson, R. and Arey, J.: Gas-phase tropospheric chemistry of biogenic volatile organic compounds: a review, Atmos. Environ., 37 (Suppl. 2), The 1997 Southern California Ozone Study (SCOS97-NARSTO), dedicated to the Memory of Dr. Glen Cass (1947–2001), S197–S219, 2003.
Belsley, D. A., Kuh, E., and Welsch, R. E.: Regression diagnostics: Identifying influential data and sources of collinearity, John Wiley & Sons, Inc., 1980.
Binkowski, F. S. and Roselle, S. J.: Models-3 Community Multi-scale Air Quality (CMAQ) model aerosol components: 1. model description, J. Geophys. Res., 108, 4183, https://doi.org/10.1029/2001JD001409, 2003.
Bonan, G. B., Levis, S., Kergoat, L., and Oleson, K. W.: Landscapes as patches of plant functional types: An integrating concept for climate and ecosystem models, Global Biogeochem. Cy., 16, 1021, https://doi.org/10.1029/2000GB001360, 2002.
Bowman, A.: An Alternative Method of cross-validation for the smoothing of density estimates, Biometrika, 71, 353–360, 1984.
Brunsdon, C., Fotheringham, A. S., and Charlton, M.: Geographically Weighted Regression:A Method for Exploring Spatial Nonstationarity, Geogr. Anal., 28, 281–289, 1996.
Brunsdon, C., Fotheringham, A. S., and Charlton, M.: Geographically weighted regression-Modeling spatial non-stationarity, The Statistician, 47, 431–443, 1998.
Brunsdon, C., Charlton, M., and Harris, P.: Living with Collinearity in Local Regression Models, in: Proceedings of the 10th International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences, Brasil, 2012.
Byun, D. W. and Ching, J. K. S.: Science algorithms of the EPA models-3 Community Multiscale Air Quality (CMAQ) modeling system, EPA/600/R-99/030, US EPA, Research Triangle Park, USA, 1999.
Byun, D. W. and Schere, K. L.: Review of the Governing Equations, Computational Algorithms, and Other Components of the Models-3 Community Multiscale Air Quality (CMAQ) Modeling System, Appl. Mech. Rev., 59, 51–77, 2006.
Carter, W. P. L.: Implementation of the SAPRC-99 chemical mechanism into the models-3 framework, Report to the United States Environmental Protection Agency, 2000a.
Carter, W. P. L.: Documentation of the SAPRC-99 Chemical Mechanism for VOC Reactivity Assessment," Report to the California Air Resources Board, Contracts 92-329 and 95-308, 8 May, available at: http://cert.ucr.edu/ carter/absts.htm#saprc99 (last access: 21 May 2013), 2000b.
Carter, W. P. L. and Seinfeld, J. H.: Winter ozone formation and VOC incremental reactivities in the Upper Green River Basin of Wyoming, Atmos. Environ., 50, 255–266, 2012.
Cleveland, W. S.: Robust locally weighted regression and smoothing scatterplots, J. Am. Stat. Assoc., 74, 829–836, 1979.
Colella, P. and Woodward, P. L.: The Piecewise Parabolic Method (PPM) for gas dynamical simulation, J. Comput. Phys., 54, 174–201, 1984.
Finlayson-Pitts, B. J. and Pitts Jr., J. N.: Chemistry of the upper and lower atmosphere, Academic Press, San Diego, CA, 2000.
Fotheringham, A. S., Brunsdon, C., and Charlton, M.: Geographically Weighted Regression: the Analysis of Spatially Varying Relationships, Wiley, Chichester, 2002.
Friedl, M. A., McIver, D. K., Hodges, J. C. F., Zhang, X. Y., Muchoney, D., Strahler, A. H., Woodcock, C. E., Gopal, S., Schneider, A., Cooper, A., Baccini, A., Gao, F., and Schaaf, C.: Global Land Cover Mapping from MODIS: Algorithms and Early Results, Remote Sens. Environ., 83, 287–302, 2002.
Gollini, I., Lu, B., Charlton, M., Brunsdon, C., and Harris, P.: GWmodel: an R Package for Exploring Spatial Heterogeneity using Geographically Weighted Models. In arXiv:1306.0413 [stat.AP], available at: http://arxiv.org/pdf/1306.0413v2.pdf (last access: 13 January 2014), 2013.
Grell, G. A., Dudhia, J., and Stauffer, D. R.: A description of the fifth-generation Penn State/NCAR mesoscale model (MM5), NCAR Technical Note, NCAR/TN-398+STR, 117 pp., 1994.
Guenther, A. and Sakulyanontvittaya, T.: Improved Biogenic Emission Inventories across the West, Technical Analysis Report for Western Governors' Association, Project Number: 06-27369, Alex Guenther, Colorado and ENVIRON International Corporation, California, available at: http://www.wrapair2.org/pdf/WGA_Task1_TechnicalAnalysisReport_ImprovedBiogenicEmissionInventories.pdf (last access: 5 February 2012), 2011.
Guenther, A., Hewitt, C. N., Erickson, D., Fall, R., Geron, C., Graedel, T., Harley, P., Klinger, L., Lerdau, M., Mckay, W. A., Pierce, T., Scholes, B., Steinbrecher, R., Tallamraju, R., Taylor, J., and Zimmerman, P. A.: Global-Model of Natural Volatile Organic-Compound Emissions, J. Geophys. Res.-Atmos., 100, 8873–8892, 1995.
Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, https://doi.org/10.5194/acp-6-3181-2006, 2006.
Hoaglin, D. C. and Welsch, R. E.: The hat matrix in regression and ANOVA, The American Statistician, 32, 17–22, 1978.
Hoerl, A. E.: Application of ridge analysis to regression problems, Chemical Engineering Progress, 58, 54–59, 1962.
Hoerl, A. E. and Kennard, R. W.: Ridge Regression: Biased Estimation for Nonorthogonal Problems, Technometrics, 12, 55–67, 1970.
Hogrefe, C., Isukapalli, S., Tang, X., Georgopoulos, P., He, S., Zalewsky, E., Hao, W., Ku, J., Key, T., and Sistla, G.: Impact of biogenic emission uncertainties on the simulated response of ozone and fine Particulate Matter to anthropogenic emission reductions, J. Air Waste Manage., 61, 92–108, 2011.
Hong, S.-Y. and Pan, H.-L.: Nonlocal boundary layer vertical diffusion in a medium-range forecast model, Mon. Weather Rev., 124, 2322–2339, 1996.
Hurvich, C. M., Simonoff, J. S., and Tsai, C. L.: Smoothing parameter selection in non-parametric regression using an improved Akaike information criterion, Journal of Real State Society, Series B (Statistic Methodology), 60, 271–293, 1998.
IPCC Climate Change 2007: The Physical Science Basis, Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L., Cambridge University Press, Cambridge, UK and New York, NY, USA, 996 pp., 2007.
Ji, M., Cohan, D. S., and Bell, M. L.: Meta-analysis of the association between short-term exposure to ambient ozone and respiratory hospital admissions, Environ. Res. Lett., 6, 024006, https://doi.org/10.1088/1748-9326/6/2/024006, 2011.
Kanamitsu, M., Ebisuzaki, W., Woollen, J., Yang, S. K., Hnilo, J. J., Fiorino, M., and Potter, G. L.: NCEP-DOE AMIP-II reanalysis (R-2), B. Am. Meteor. Soc., 83, 1631–1643, 2002.
Loader, C. R.: Bandwidth selection: classical or plug-in?, The Annals of Statistics, 27, 415–438, 1999.
Lu, B., Harris, P., Charlton, M., Brunsdon, C., Nakaya, T., Gollini, I., and Lu, M. B.: Package "GWmodel" Version 1.2-2, available at: http://cran.r-project.org/src/contrib/Archive/GWmodel/ (last access: 13 January 2014), 2013.
O'Brien, R.: A caution regarding rules of thumb for variance inflation factors, Qual. Quant., 41, 673–690, 2007.
Pfister, G. G., Emmons, L. K., Hess, P. G., Lamarque, J. F., Orlando, J. J., Walters, S., Guenther, A., Palmer, P. I., and Lawrence, P. J.: Contribution of isoprene to chemical budgets: A model tracer study with the NCAR CTM MOZART-4, J. Geophys. Res., 113, D05308, https://doi.org/10.1029/2007JD008948, 2008.
Pleim, J. E. and Chang, J. S.: A non-local closure model in the convective boundary layer, Atmos. Environ. A-Gen., 26, 965–981, 1992.
Reisner, J., Rasmussen, R. J., and Bruintjes, R. T.: Explicit forecasting of supercooled liquid water in winter storms using MM5 mesoscale model, Q. J. Roy. Meteor. Soc., 124B, 1071–1107, 1998.
Russell, A. G. and Dennis, R.: NARSTO critical review of photochemical models and modeling. Atmos. Environ., 34, 2284–2324, 2000.
Smith, T. M., Shugart, H. H., and Woodward, F. I. (Eds.): Plant functional types: Their relevance to ecosystem properties and global change, International geosphere-biosphere programme book series 1, Cambridge University Press, Cambridge, 1997.
Strahler, A., Muchoney, D., Borak, J., Friedl, M. A., Gopal, S., Lambin, E., and Moody, A.: MODIS land cover product algorithm theoretical basis document (ATBD) (Version 5.0), available at: http://modis.gsfc.nasa.gov/data/atbd/atbd_mod12.pdf(last access: 3 July 2009), 1999.
Streets, D. G., Bond, T. C., Carmichael, G. R., Fernandes, S. D., Fu, Q., He, D., Klimont, Z., Nelson, S. M., Tsai, N. Y., Wang, M. Q., Woo, J.-H., and Yarber, K. F.: An inventory of gaseous and primary aerosol emissions in Asia in the year 2000, J. Geophys. Res., 108, 8809, https://doi.org/10.1029/2002JD003093, 2003.
Sun, W., Liang, S., Xu, G., Fang, H., and Dickinson, R.: Mapping plant functional types from MODIS data using multisource evidential reasoning, Remote Sens. Environ., 112, 1010–1024, 2008.
Tao, Z., Larson, S. M., Wuebbles, D. J., Williams, A., and Caughey, M.: A Summer Simulation of Biogenic Contributions to Ground-Level Ozone over the Continental United States. J. Geophys. Res., 108, 4404, https://doi.org/10.1029/2002JD002945, 2003.
Woo, J.-H., Choi, K.-C., Kim, H.-K., Baek, B. H., Jang, M. D., Eum, J.-H., Song, C. H., Ma, Y.-I., Young Sunwoo, Y., Chang, L.-S., and Yoo, Y. H.: Development of an anthropogenic emissions processing system for Asia using SMOKE, Atmos. Environ., 58, 5–13, 2012.
Xie, X., Shao, M., Liu, Y., Lu, S. H., Chang, C. C., and Chen, Z. M.: Estimate of initial isoprene contribution to ozone formation potential in Beijing, China, Atmos. Environ., 42, 6000–6010, 2008.
Zhang, Q., Streets, D. G., Carmichael, G. R., He, K. B., Huo, H., Kannari, A., Klimont, Z., Park, I. S., Reddy, S., Fu, J. S., Chen, D., Duan, L., Lei, Y., Wang, L. T., and Yao, Z. L.: Asian emissions in 2006 for the NASA INTEX-B mission, Atmos. Chem. Phys., 9, 5131–5153, https://doi.org/10.5194/acp-9-5131-2009, 2009.
Zheng, J. Y., Shao, M., Che, W. W., Zhang, L. J., Zhong, L. J., Zhang, Y. H., and Streets, D. G.: Speciated VOC emission inventory and spatial patterns of ozone formation potential in the Pearl River Delta, China, Environ. Sci. Technol., 43, 8580–8586, 2009.