Articles | Volume 16, issue 23
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Variability of winter and summer surface ozone in Mexico City on the intraseasonal timescale
Bradford S. Barrett
Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
Oceanography Department, US Naval Academy, Annapolis, MD 21401, USA
No articles found.
Diana L. Pereira, Irma Gavilán, Consuelo Letechipía, Graciela B. Raga, Teresa Pi Puig, Violeta Mugica-Álvarez, Harry Alvarez-Ospina, Irma Rosas, Leticia Martinez, Eva Salinas, Erika T. Quintana, Daniel Rosas, and Luis A. Ladino
Atmos. Chem. Phys., 22, 6435–6447,Short summary
Airborne particles were i) collected in an agricultural fields and ii) generated in the laboratory from agricultural soil samples to analyze their ice nucleating abilities. It was found that the size and chemical composition of the Mexican agricultural dust particles influence their ice nucleating behavior, where the organic components are likely responsible for their efficiency as INPs. The INP concentrations from the present study are comparable to those from higher latitudes.
Graciela B. Raga, Darrel Baumgardner, Blanca Rios, Yanet Díaz-Esteban, Alejandro Jaramillo, Martin Gallagher, Bastien Sauvage, Pawel Wolff, and Gary Lloyd
Atmos. Chem. Phys., 22, 2269–2292,Short summary
The In-Service Aircraft for a Global Observing System (IAGOS) is a small fleet of commercial aircraft that carry a suite of meteorological, gas, aerosol, and cloud sensors and have been measuring worldwide for almost 9 years, since late 2011. Extreme ice events (EIEs) have been identified from the IAGOS cloud measurements and linked to surface emissions for biomass and fossil fuel consumption. The results reported here are highly relevant for climate change and flight operations forecasting.
Fernanda Córdoba, Carolina Ramírez-Romero, Diego Cabrera, Graciela B. Raga, Javier Miranda, Harry Alvarez-Ospina, Daniel Rosas, Bernardo Figueroa, Jong Sung Kim, Jacqueline Yakobi-Hancock, Talib Amador, Wilfrido Gutierrez, Manuel García, Allan K. Bertram, Darrel Baumgardner, and Luis A. Ladino
Atmos. Chem. Phys., 21, 4453–4470,Short summary
Most precipitation from deep clouds over the continents and in the intertropical convergence zone is strongly influenced by the presence of ice crystals whose formation requires the presence of aerosol particles. In the present study, the ability of three different aerosol types (i.e., marine aerosol, biomass burning, and African dust) to facilitate ice particle formation was assessed in the Yucatán Peninsula, Mexico.
Carolina Ramírez-Romero, Alejandro Jaramillo, María F. Córdoba, Graciela B. Raga, Javier Miranda, Harry Alvarez-Ospina, Daniel Rosas, Talib Amador, Jong Sung Kim, Jacqueline Yakobi-Hancock, Darrel Baumgardner, and Luis A. Ladino
Atmos. Chem. Phys., 21, 239–253,Short summary
Field measurements were conducted to confirm the arrival of African dust on the Yucatàn Peninsula. Aerosol particles were monitored at ground level by different online and off-line sensors. Several particulate matter peaks were observed with a relative increase in their levels of up to 500 % with respect to background conditions. Based on the chemical composition, back trajectories, vertical profiles, reanalysis, and satellite images, it was found that the peaks are linked to African dust.
Lester Alfonso, Graciela B. Raga, and Darrel Baumgardner
Atmos. Chem. Phys., 19, 14917–14932,Short summary
The aim of this paper is to find some observational evidence of gel formation in clouds, by analyzing the distribution of the largest droplet at an early stage of cloud formation, and to show that the mass of the gel (
lucky droplet) is a mixture of Gaussian and Gumbel distributions. The results obtained may help advance the understanding of precipitation formation and are a novel application of the theory of critical phenomena in cloud physics.
Luis A. Ladino, Graciela B. Raga, Harry Alvarez-Ospina, Manuel A. Andino-Enríquez, Irma Rosas, Leticia Martínez, Eva Salinas, Javier Miranda, Zyanya Ramírez-Díaz, Bernardo Figueroa, Cedric Chou, Allan K. Bertram, Erika T. Quintana, Luis A. Maldonado, Agustín García-Reynoso, Meng Si, and Victoria E. Irish
Atmos. Chem. Phys., 19, 6147–6165,Short summary
This study presents results obtained during a field campaign conducted in the tropical village of Sisal located on the coast of the Gulf of Mexico. Air masses arriving in Sisal during the passage of cold fronts have surprisingly higher ice-nucleating particle (INP) concentrations than the campaign average. The high concentrations of INPs at T > −15 C and the supermicron size of the INPs suggest that biological particles may have been a significant contributor to the INP population in Sisal.
Lester Alfonso and Graciela B. Raga
Atmos. Chem. Phys., 17, 6895–6905,Short summary
The main hypothesis of this work is that the discrepancy between the observations and the theoretical models of precipitation formation in warm clouds could be explained by the formation of embryo droplets in the context of a sol–gel transition. By using novel numerical techniques, our calculations show that after the formation of the raindrop embryo, the droplet mass distribution strongly differs from the results obtained by using the traditional approaches.
Ana Graciela Ulke, Marcela M. Torres Brizuela, Graciela B. Raga, and Darrel Baumgardner
Nat. Hazards Earth Syst. Sci., 16, 2159–2175,Short summary
The eruption in June 2011 of the Puyehue-Cordón Caulle Volcanic Complex (Chile) impacted air traffic around the Southern Hemisphere for several months. The ash deposited in vast areas of the Patagonian steppe was subjected to the strong wind conditions prevalent during the austral winter and spring. An ash resuspension event impacted Buenos Aires and resulted in the closure of airports in the area on 16 October 2011. Measurements of aerosol properties clearly indicate the enhanced concentrations
A. Retama, D. Baumgardner, G. B. Raga, G. R. McMeeking, and J. W. Walker
Atmos. Chem. Phys., 15, 9693–9709,Short summary
Extended measurements of equivalent black carbon (eBC) derived from light absorption measurements have been made with a PAX over a 13 month period. The daily trends in eBC and other co-pollutants are evaluated with respect to season. The primary factors that led to large changes between the wet and dry seasons are the accelerated vertical mixing of boundary layer and free tropospheric air, by the formation of clouds and decreased actinic flux that reduces the production of ozone.
G. B. Raga, D. Baumgardner, A. G. Ulke, M. Torres Brizuela, and B. Kucienska
Nat. Hazards Earth Syst. Sci., 13, 2319–2330,
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)Transport pathways of carbon monoxide from Indonesian fire pollution to a subtropical high-altitude mountain site in the western North PacificGlobal warming will largely increase waste treatment CH4 emissions in Chinese megacities: insight from the first city-scale CH4 concentration observation network in Hangzhou, ChinaDisentangling methane and carbon dioxide sources and transport across the Russian Arctic from aircraft measurementsAirborne glyoxal measurements in the marine and continental atmosphere: comparison with TROPOMI observations and EMAC simulationsMercury in the free troposphere and bidirectional atmosphere–vegetation exchanges – insights from Maïdo mountain observatory in the Southern Hemisphere tropicsDiurnal variability of atmospheric O2, CO2, and their exchange ratio above a boreal forest in southern FinlandHow adequately are elevated moist layers represented in reanalysis and satellite observations?Quantitative impacts of vertical transport on the long-term trend of nocturnal ozone increase over the Pearl River Delta region during 2006–2019Factors influencing the temporal variability of atmospheric methane emissions from Upper Silesia coal mines: a case study from the CoMet missionEnhanced natural releases of mercury in response to the reduction in anthropogenic emissions during the COVID-19 lockdown by explainable machine learningQuantification of methane emissions in Hamburg using a network of FTIR spectrometers and an inverse modeling approachTemporal variability of tropospheric ozone and ozone profiles in the Korean Peninsula during the East Asian summer monsoon: insights from multiple measurements and reanalysis datasetsRetrieving CH4-emission rates from coal mine ventilation shafts using UAV-based AirCore observations and the genetic algorithm–interior point penalty function (GA-IPPF) modelMeasurement report: Atmospheric mercury in a coastal city of Southeast China – inter-annual variations and influencing factorsTropospheric and stratospheric ozone profiles during the 2019 TROpomi vaLIdation eXperiment (TROLIX-19)Evaluation of correlated Pandora column NO2 and in situ surface NO2 measurements during GMAP campaignTransport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convectionObservational constraints on methane emissions from Polish coal mines using a ground-based remote sensing networkContinuous CH4 and δ13CH4 measurements in London demonstrate under-reported natural gas leakageLong-term fluxes of carbonyl sulfide and their seasonality and interannual variability in a boreal forestDeclines and peaks in NO2 pollution during the multiple waves of the COVID-19 pandemic in the New York metropolitan areaLocal to regional methane emissions from the Upper Silesia Coal Basin (USCB) quantified using UAV-based atmospheric measurementsMeasurement report: Characterization of uncertainties in fluxes and fuel sulfur content from ship emissions in the Baltic SeaLimitations of the radon tracer method (RTM) to estimate regional greenhouse gas (GHG) emissions – a case study for methane in HeidelbergPositive and negative influences of typhoons on tropospheric ozone over southern ChinaSpatial and temporal variations of CO2 mole fractions observed at Beijing, Xianghe, and Xinglong in North ChinaThe CO2 integral emission by the megacity of St Petersburg as quantified from ground-based FTIR measurements combined with dispersion modellingAnthropogenic and natural controls on atmospheric δ13C-CO2 variations in the Yangtze River delta: insights from a carbon isotope modeling frameworkQuantifying variability, source, and transport of CO in the urban areas over the Himalayas and Tibetan PlateauNew methodology shows short atmospheric lifetimes of oxidized sulfur and nitrogen due to dry depositionUncertainties in eddy covariance air–sea CO2 flux measurements and implications for gas transfer velocity parameterisationsConvergent evidence for the pervasive but limited contribution of biomass burning to atmospheric ammonia in peninsular Southeast AsiaConcurrent variation in oil and gas methane emissions and oil price during the COVID-19 pandemicOzone variability induced by synoptic weather patterns in warm seasons of 2014–2018 over the Yangtze River Delta region, ChinaSeasonal patterns of atmospheric mercury in tropical South America as inferred by a continuous total gaseous mercury record at Chacaltaya station (5240 m) in BoliviaA mass-weighted isentropic coordinate for mapping chemical tracers and computing atmospheric inventoriesMethane mapping, emission quantification, and attribution in two European cities: Utrecht (NL) and Hamburg (DE)Ozone affected by a succession of four landfall typhoons in the Yangtze River Delta, China: major processes and health impacts4D dispersion of total gaseous mercury derived from a mining source: identification of criteria to assess risks related to high concentrations of atmospheric mercuryEstimating CH4, CO2 and CO emissions from coal mining and industrial activities in the Upper Silesian Coal Basin using an aircraft-based mass balance approachProfiling of formaldehyde, glyoxal, methylglyoxal, and CO over the Amazon: normalized excess mixing ratios and related emission factors in biomass burning plumesMeasurement report: Leaf-scale gas exchange of atmospheric reactive trace species (NO2, NO, O3) at a northern hardwood forest in MichiganA dedicated flask sampling strategy developed for Integrated Carbon Observation System (ICOS) stations based on CO2 and CO measurements and Stochastic Time-Inverted Lagrangian Transport (STILT) footprint modellingThe increasing atmospheric burden of the greenhouse gas sulfur hexafluoride (SF6)Understanding nighttime methane signals at the Amazon Tall Tower Observatory (ATTO)Background heterogeneity and other uncertainties in estimating urban methane flux: results from the Indianapolis Flux Experiment (INFLUX)Methane emissions from the Munich OktoberfestA study of the influence of tropospheric subsidence on spring and summer surface ozone concentrations at the JRC Ispra station in northern ItalyLocal and synoptic meteorological influences on daily variability in summertime surface ozone in eastern ChinaVariability in a four-network composite of atmospheric CO2 differences between three primary baseline sites
Saginela Ravindra Babu, Chang-Feng Ou-Yang, Stephen M. Griffith, Shantanu Kumar Pani, Steven Soon-Kai Kong, and Neng-Huei Lin
Atmos. Chem. Phys., 23, 4727–4740,Short summary
In October 2006 and 2015, extensive fire episodes occurred in Indonesia, releasing an enormous amount of CO emissions. By combining in situ and satellite CO measurements and reanalysis products, we reported plausible transport pathways of CO from Indonesia to the Lulin Atmospheric Background Station (LABS; 23.47° N, 120.87° E; 2862 m a.s.l.) in Taiwan. We identified (i) horizontal transport in the free troposphere and (ii) vertical transport through the Hadley circulation.
Cheng Hu, Junqing Zhang, Bing Qi, Rongguang Du, Xiaofei Xu, Haoyu Xiong, Huili Liu, Xinyue Ai, Yiyi Peng, and Wei Xiao
Atmos. Chem. Phys., 23, 4501–4520,Short summary
We build the first city-scale tower-based atmospheric CH4 concentration observation network in China. The a priori total annual anthropogenic CH4 emissions and emissions from waste treatment were overestimated by 36.0 % and 47.1 %, respectively, in Hangzhou. Global warming will largely enhance the CH4 emission factor of waste treatment, which will increase by 17.6 %, 9.6 %, 5.6 % and 4.0 % for Representative Concentration Pathway (RCP) 8.5, RCP6.0, RCP4.5 and RCP2.6, respectively, by 2100.
Clément Narbaud, Jean-Daniel Paris, Sophie Wittig, Antoine Berchet, Marielle Saunois, Philippe Nédélec, Boris D. Belan, Mikhail Y. Arshinov, Sergei B. Belan, Denis Davydov, Alexander Fofonov, and Artem Kozlov
Atmos. Chem. Phys., 23, 2293–2314,Short summary
We measured CH4 and CO2 from aircraft over the Russian Arctic. Analyzing our data with the Lagrangian model FLEXPART, we find a sharp east–west gradient in atmospheric composition. Western Siberia is influenced by strong wetland CH4 emissions, deep CO2 gradient from biospheric uptake, and long-range transport from Europe and North America. Eastern flights document less variability. Over the Arctic Ocean, we find a small influence from marine CH4 emissions compatible with reasonable inventories.
Flora Kluge, Tilman Hüneke, Christophe Lerot, Simon Rosanka, Meike K. Rotermund, Domenico Taraborrelli, Benjamin Weyland, and Klaus Pfeilsticker
Atmos. Chem. Phys., 23, 1369–1401,Short summary
Using airborne glyoxal concentration and vertical column density measurements, vertical profiles are inferred for eight global regions in aged biomass burning plumes and the tropical marine boundary layer. Using TROPOMI observations, an analysis of space- and airborne measurements is performed. A comparison to EMAC simulations shows a general glyoxal underprediction, which points to various missing sources and precursors from anthropogenic activities, biomass burning, and the sea surface.
Alkuin M. Koenig, Olivier Magand, Bert Verreyken, Jerome Brioude, Crist Amelynck, Niels Schoon, Aurélie Colomb, Beatriz Ferreira Araujo, Michel Ramonet, Mahesh K. Sha, Jean-Pierre Cammas, Jeroen E. Sonke, and Aurélien Dommergue
Atmos. Chem. Phys., 23, 1309–1328,Short summary
The global distribution of mercury, a potent neurotoxin, depends on atmospheric transport, chemistry, and interactions between the Earth’s surface and the air. Our understanding of these processes is still hampered by insufficient observations. Here, we present new data from a mountain observatory in the Southern Hemisphere. We give insights into mercury concentrations in air masses coming from aloft, and we show that tropical mountain vegetation may be a daytime source of mercury to the air.
Kim A. P. Faassen, Linh N. T. Nguyen, Eadin R. Broekema, Bert A. M. Kers, Ivan Mammarella, Timo Vesala, Penelope A. Pickers, Andrew C. Manning, Jordi Vilà-Guerau de Arellano, Harro A. J. Meijer, Wouter Peters, and Ingrid T. Luijkx
Atmos. Chem. Phys., 23, 851–876,Short summary
The exchange ratio (ER) between atmospheric O2 and CO2 provides a useful tracer for separately estimating photosynthesis and respiration processes in the forest carbon balance. This is highly relevant to better understand the expected biosphere sink, which determines future atmospheric CO2 levels. We therefore measured O2, CO2, and their ER above a boreal forest in Finland and investigated their diurnal behaviour for a representative day, and we show the most suitable way to determine the ER.
Marc Prange, Stefan A. Buehler, and Manfred Brath
Atmos. Chem. Phys., 23, 725–741,Short summary
We investigate the representation of elevated moist layers (EMLs) in two satellite retrieval products and ERA5 reanalysis. EMLs occur in the vicinity of tropical convective storms and are thought to have an impact on their evolution through radiative heating. We provide a first dedicated assessment of EMLs in long-term data products in terms of moist layer strength, vertical thickness and altitude by comparing to collocated radiosondes over the western Pacific, a region where EMLs often occur.
Yongkang Wu, Weihua Chen, Yingchang You, Qianqian Xie, Shiguo Jia, and Xuemei Wang
Atmos. Chem. Phys., 23, 453–469,Short summary
Relying on observed and simulated data, we determine the spatiotemporal characteristics of nocturnal O3 increase (NOI) events in the Pearl River Delta region during 2006–2019. Low-level jets and convective storms are the main meteorological processes causing NOI. Daytime O3 is another essential influencing factor. More importantly, a more prominent role of meteorological processes in NOI has been demonstrated. Our study highlights the important role of meteorology in nocturnal O3 pollution.
Justyna Swolkień, Andreas Fix, and Michał Gałkowski
Atmos. Chem. Phys., 22, 16031–16052,Short summary
Determination of emissions from coal mines on a local scale requires instantaneous data. We analysed temporal emission data for ventilation shafts and factors influencing their variability. They were saturation of the seams with methane, the permeability of the rock mass, and coal output. The data for the verification should reflect the actual values of emissions from point sources. It is recommended to achieve this by using a standardised emission measurement system for all coal mines.
Xiaofei Qin, Shengqian Zhou, Hao Li, Guochen Wang, Cheng Chen, Chengfeng Liu, Xiaohao Wang, Juntao Huo, Yanfen Lin, Jia Chen, Qingyan Fu, Yusen Duan, Kan Huang, and Congrui Deng
Atmos. Chem. Phys., 22, 15851–15865,Short summary
Using artificial neural network modeling and an explainable analysis approach, natural surface emissions (NSEs) were identified as a main driver of gaseous elemental mercury (GEM) variations during the COVID-19 lockdown. A sharp drop in GEM concentrations due to a significant reduction in anthropogenic emissions may disrupt the surface–air exchange balance of Hg, leading to increases in NSEs. This implies that NSEs may pose challenges to the future control of Hg pollution.
Andreas Forstmaier, Jia Chen, Florian Dietrich, Juan Bettinelli, Hossein Maazallahi, Carsten Schneider, Dominik Winkler, Xinxu Zhao, Taylor Jones, Carina van der Veen, Norman Wildmann, Moritz Makowski, Aydin Uzun, Friedrich Klappenbach, Hugo Denier van der Gon, Stefan Schwietzke, and Thomas Röckmann
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
Large cities emit greenhouse gases which contribute to global warming. In this study we measured the release of one important green house gas, methane in the Hamburg. Multiple sources that contribute to the methane emissions were located and quantified. Methane sources were found to be mainly caused by human activity, for example by the release from oil and gas refineries. Also potential natural sources have been located such as the Elbe river and lakes.
Juseon Bak, Eun-Ji Song, Hyo-Jung Lee, Xiong Liu, Ja-Ho Koo, Joowan Kim, Wonbae Jeon, Jae-Hwan Kim, and Cheol-Hee Kim
Atmos. Chem. Phys., 22, 14177–14187,Short summary
Our study investigates the temporal variations of ozone profiles at Pohang in the Korean Peninsula from multiple ozone products. We discuss the quantitative relationships between daily surface measurements and key meteorological variables, different seasonality of ozone between the troposphere and stratosphere, and interannual changes in the lower tropospheric ozone, linked by the weather pattern driven by the East Asian summer monsoon.
Tianqi Shi, Zeyu Han, Ge Han, Xin Ma, Huilin Chen, Truls Andersen, Huiqin Mao, Cuihong Chen, Haowei Zhang, and Wei Gong
Atmos. Chem. Phys., 22, 13881–13896,Short summary
CH4 works as the second-most important greenhouse gas, its reported emission inventories being far less than CO2. In this study, we developed a self-adjusted model to estimate the CH4 emission rate from strong point sources by the UAV-based AirCore system. This model would reduce the uncertainty in CH4 emission rate quantification accrued by errors in measurements of wind and concentration. Actual measurements on Pniówek coal demonstrate the high accuracy and stability of our developed model.
Jiayan Shi, Yuping Chen, Lingling Xu, Youwei Hong, Mengren Li, Xiaolong Fan, Liqian Yin, Yanting Chen, Chen Yang, Gaojie Chen, Taotao Liu, Xiaoting Ji, and Jinsheng Chen
Atmos. Chem. Phys., 22, 11187–11202,Short summary
Gaseous elemental mercury (GEM) was observed in Southeast China over the period 2012–2020. The observed GEM concentrations showed no distinct inter-annual variation trends. The interpretation rate of transportation and meteorology on GEM variations displayed an increasing trend. In contrast, anthropogenic emissions have shown a decreasing interpretation rate since 2012, indicating the effectiveness of emission mitigation measures in reducing GEM concentrations in the study region.
John T. Sullivan, Arnoud Apituley, Nora Mettig, Karin Kreher, K. Emma Knowland, Marc Allaart, Ankie Piters, Michel Van Roozendael, Pepijn Veefkind, Jerry R. Ziemke, Natalya Kramarova, Mark Weber, Alexei Rozanov, Laurence Twigg, Grant Sumnicht, and Thomas J. McGee
Atmos. Chem. Phys., 22, 11137–11153,Short summary
A TROPOspheric Monitoring Instrument (TROPOMI) validation campaign (TROLIX-19) was held in the Netherlands in September 2019. The research presented here focuses on using ozone lidars from NASA’s Goddard Space Flight Center to better evaluate the characterization of ozone throughout TROLIX-19 as compared to balloon-borne, space-borne and ground-based passive measurements, as well as a global coupled chemistry meteorology model.
Lim-Seok Chang, Donghee Kim, Hyunkee Hong, Deok-Rae Kim, Jeong-Ah Yu, Kwangyul Lee, Hanlim Lee, Daewon Kim, Jinkyu Hong, Hyun-Young Jo, and Cheol-Hee Kim
Atmos. Chem. Phys., 22, 10703–10720,Short summary
Our study explored the synergy of combined column and surface measurements during GMAP (GEMS Map of Air Pollution) campaign. It has several points to note for vertical distribution analysis. Particularly under prevailing local wind meteorological conditions, Pandora-based vertical structures sometimes showed negative correlations between column and surface measurements. Vertical analysis should be done carefully in some local meteorological conditions when employing either surface or columns.
Zhixiong Chen, Jane Liu, Xiushu Qie, Xugeng Cheng, Yukun Shen, Mengmiao Yang, Rubin Jiang, and Xiangke Liu
Atmos. Chem. Phys., 22, 8221–8240,Short summary
A vigorous surface ozone surge event of stratospheric origin occurred in the North China Plain at night. Surface ozone concentrations were 40–50 ppbv higher than the corresponding monthly mean, whereas surface carbon monoxide concentrations declined abruptly, which confirmed the direct stratospheric intrusions to the surface. We further addressed the notion that a combined effect of the dying typhoon and mesoscale convective systems was responsible for this vigorous ozone surge.
Andreas Luther, Julian Kostinek, Ralph Kleinschek, Sara Defratyka, Mila Stanisavljević, Andreas Forstmaier, Alexandru Dandocsi, Leon Scheidweiler, Darko Dubravica, Norman Wildmann, Frank Hase, Matthias M. Frey, Jia Chen, Florian Dietrich, Jarosław Nȩcki, Justyna Swolkień, Christoph Knote, Sanam N. Vardag, Anke Roiger, and André Butz
Atmos. Chem. Phys., 22, 5859–5876,Short summary
Coal mining is an extensive source of anthropogenic methane emissions. In order to reduce and mitigate methane emissions, it is important to know how much and where the methane is emitted. We estimated coal mining methane emissions in Poland based on atmospheric methane measurements and particle dispersion modeling. In general, our emission estimates suggest higher emissions than expected by previous annual emission reports.
Eric Saboya, Giulia Zazzeri, Heather Graven, Alistair J. Manning, and Sylvia Englund Michel
Atmos. Chem. Phys., 22, 3595–3613,Short summary
Continuous measurements of atmospheric methane concentrations and its carbon-13 isotope have been made in central London since early 2018. These measurements were used to evaluate methane emissions reported in global and UK-specific emission inventories for the London area. Compared to atmospheric methane measurements from March 2018 to October 2020, both inventories are under-reporting natural gas leakage for the London area.
Timo Vesala, Kukka-Maaria Kohonen, Linda M. J. Kooijmans, Arnaud P. Praplan, Lenka Foltýnová, Pasi Kolari, Markku Kulmala, Jaana Bäck, David Nelson, Dan Yakir, Mark Zahniser, and Ivan Mammarella
Atmos. Chem. Phys., 22, 2569–2584,Short summary
Carbonyl sulfide (COS) provides new insights into carbon cycle research. We present an easy-to-use flux parameterization and the longest existing time series of forest–atmosphere COS exchange measurements, which allow us to study both seasonal and interannual variability. We observed only uptake of COS by the forest on an annual basis, with 37 % variability between years. Upscaling the boreal COS uptake using a biosphere model indicates a significant missing COS sink at high latitudes.
Maria Tzortziou, Charlotte F. Kwong, Daniel Goldberg, Luke Schiferl, Róisín Commane, Nader Abuhassan, James J. Szykman, and Lukas C. Valin
Atmos. Chem. Phys., 22, 2399–2417,Short summary
The COVID-19 pandemic created an extreme natural experiment in which sudden changes in human behavior significantly impacted urban air quality. Using a combination of model, satellite, and ground-based data, we examine the impact of multiple waves and phases of the pandemic on atmospheric nitrogen pollution in the New York metropolitan area, and address the role of weather as a key driver of high pollution episodes observed even during – and despite – the stringent early lockdowns.
Truls Andersen, Marcel de Vries, Jaroslaw Necki, Justyna Swolkien, Malika Menoud, Thomas Röckmann, Anke Roiger, Andreas Fix, Wouter Peters, and Huilin Chen
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
The Upper Silesian Coal Basin, Poland is one of the hot spots of methane emissions in Europe. Using an unmanned aerial vehicle (UAV), we performed atmospheric measurements of methane concentrations downwind of five ventilation shafts in this region and determined the emission rates from the individual shafts. We found a strong correlation between quantified shaft-averaged emission rates and hourly inventory data, which also allows us to estimate the methane emissions from the entire region.
Jari Walden, Liisa Pirjola, Tuomas Laurila, Juha Hatakka, Heidi Pettersson, Tuomas Walden, Jukka-Pekka Jalkanen, Harri Nordlund, Toivo Truuts, Miika Meretoja, and Kimmo K. Kahma
Atmos. Chem. Phys., 21, 18175–18194,Short summary
Ship emissions play an important role in the deposition of gaseous compounds and nanoparticles (Ntot), affecting climate, human health (especially in coastal areas), and eutrophication. Micrometeorological methods showed that ship emissions were mainly responsible for the deposition of Ntot, whereas they only accounted for a minor proportion of CO2 deposition. An uncertainty analysis applied to the fluxes and fuel sulfur content results demonstrated the reliability of the results.
Ingeborg Levin, Ute Karstens, Samuel Hammer, Julian DellaColetta, Fabian Maier, and Maksym Gachkivskyi
Atmos. Chem. Phys., 21, 17907–17926,Short summary
The radon tracer method is applied to atmospheric methane and radon observations from the upper Rhine valley to independently estimate methane emissions from the region. Comparison of our top-down results with bottom-up inventory data requires high-resolution footprint modelling and representative radon flux data. In agreement with inventories, observed emissions decreased, but only until 2005. A limitation of this method is that point-source emissions are not captured or not fully captured.
Zhixiong Chen, Jane Liu, Xugeng Cheng, Mengmiao Yang, and Hong Wang
Atmos. Chem. Phys., 21, 16911–16923,Short summary
Using a large ensemble of typhoons, we investigate the impacts of evolving typhoons on tropospheric ozone and address the linkages between typhoon-affected meteorological conditions and ozone variations. The influences of typhoon-induced stratospheric intrusions on lower-troposphere ozone are also quantified. Thus, the results obtained in this study have important implications for a full understanding of the multifaced roles of typhoons in modulating tropospheric ozone variation.
Yang Yang, Minqiang Zhou, Ting Wang, Bo Yao, Pengfei Han, Denghui Ji, Wei Zhou, Yele Sun, Gengchen Wang, and Pucai Wang
Atmos. Chem. Phys., 21, 11741–11757,Short summary
This study introduces the in situ CO2 measurement system installed in Beijing (urban), Xianghe (suburban), and Xinglong (rural) in North China for the first time. The spatial and temporal variations in CO2 mole fractions at the three sites between June 2018 and April 2020 are discussed on both seasonal and diurnal scales.
Dmitry V. Ionov, Maria V. Makarova, Frank Hase, Stefani C. Foka, Vladimir S. Kostsov, Carlos Alberti, Thomas Blumenstock, Thorsten Warneke, and Yana A. Virolainen
Atmos. Chem. Phys., 21, 10939–10963,Short summary
Megacities are a significant source of emissions of various substances in the atmosphere, including carbon dioxide, which is the most important anthropogenic greenhouse gas. In 2019–2020, the Emission Monitoring Mobile Experiment was carried out in St Petersburg, which is the second-largest industrial city in Russia. The results of this experiment, coupled with numerical modelling, helped to estimate the amount of CO2 emitted by the city. This value was twice as high as predicted.
Cheng Hu, Jiaping Xu, Cheng Liu, Yan Chen, Dong Yang, Wenjing Huang, Lichen Deng, Shoudong Liu, Timothy J. Griffis, and Xuhui Lee
Atmos. Chem. Phys., 21, 10015–10037,Short summary
Seventy percent of global CO2 emissions were emitted from urban landscapes. The Yangtze River delta (YRD) ranks as one of the most densely populated regions in the world and is an anthropogenic CO2 hotspot. Besides anthropogenic factors, natural ecosystems and croplands act as significant CO2 sinks and sources. Independent quantification of the fossil and cement CO2 emission and assessment of their impact on atmospheric δ13C-CO2 have potential to improve our understanding of urban CO2 cycling.
Youwen Sun, Hao Yin, Yuan Cheng, Qianggong Zhang, Bo Zheng, Justus Notholt, Xiao Lu, Cheng Liu, Yuan Tian, and Jianguo Liu
Atmos. Chem. Phys., 21, 9201–9222,Short summary
We quantified the variability, source, and transport of urban CO over the Himalayas and Tibetan Plateau (HTP) by using measurement, model simulation, and the analysis of meteorological fields. Urban CO over the HTP is dominated by anthropogenic and biomass burning emissions from local, South Asia and East Asia, and oxidation sources. The decreasing trends in surface CO since 2015 in most cities over the HTP are attributed to the reduction in local and transported CO emissions in recent years.
Katherine Hayden, Shao-Meng Li, Paul Makar, John Liggio, Samar G. Moussa, Ayodeji Akingunola, Robert McLaren, Ralf M. Staebler, Andrea Darlington, Jason O'Brien, Junhua Zhang, Mengistu Wolde, and Leiming Zhang
Atmos. Chem. Phys., 21, 8377–8392,Short summary
We developed a method using aircraft measurements to determine lifetimes with respect to dry deposition for oxidized sulfur and nitrogen compounds over the boreal forest in Alberta, Canada. Atmospheric lifetimes were significantly shorter than derived from chemical transport models with differences related to modelled dry deposition velocities. The shorter lifetimes suggest models need to reassess dry deposition treatment and predictions of sulfur and nitrogen in the atmosphere and ecosystems.
Yuanxu Dong, Mingxi Yang, Dorothee C. E. Bakker, Vassilis Kitidis, and Thomas G. Bell
Atmos. Chem. Phys., 21, 8089–8110,Short summary
Eddy covariance (EC) is the most direct method for measuring air–sea CO2 flux from ships. However, uncertainty in EC air–sea CO2 fluxes has not been well quantified. Here we show that with the state-of-the-art gas analysers, instrumental noise no longer contributes significantly to the CO2 flux uncertainty. Applying an appropriate averaging timescale (1–3 h) and suitable air–sea CO2 fugacity threshold (at least 20 µatm) to EC flux data enables an optimal analysis of the gas transfer velocity.
Yunhua Chang, Yan-Lin Zhang, Sawaeng Kawichai, Qian Wang, Martin Van Damme, Lieven Clarisse, Tippawan Prapamontol, and Moritz F. Lehmann
Atmos. Chem. Phys., 21, 7187–7198,Short summary
In this study, we integrated satellite constraints on atmospheric NH3 levels and fire intensity, discrete NH3 concentration measurement, and N isotopic analysis of NH3 in order to assess the regional-scale contribution of biomass burning to ambient atmospheric NH3 in the heartland of Southeast Asia. The combined approach provides a valuable cross-validation framework for source apportioning of NH3 in the lower atmosphere and will thus help to ameliorate predictions of biomass burning emissions.
David R. Lyon, Benjamin Hmiel, Ritesh Gautam, Mark Omara, Katherine A. Roberts, Zachary R. Barkley, Kenneth J. Davis, Natasha L. Miles, Vanessa C. Monteiro, Scott J. Richardson, Stephen Conley, Mackenzie L. Smith, Daniel J. Jacob, Lu Shen, Daniel J. Varon, Aijun Deng, Xander Rudelis, Nikhil Sharma, Kyle T. Story, Adam R. Brandt, Mary Kang, Eric A. Kort, Anthony J. Marchese, and Steven P. Hamburg
Atmos. Chem. Phys., 21, 6605–6626,Short summary
The Permian Basin (USA) is the world’s largest oil field. We use tower- and aircraft-based approaches to measure how methane emissions in the Permian Basin changed throughout 2020. In early 2020, 3.3 % of the region’s gas was emitted; then in spring 2020, the loss rate temporarily dropped to 1.9 % as oil price crashed. We find this short-term reduction to be a result of reduced well development, less gas flaring, and fewer abnormal events despite minimal reductions in oil and gas production.
Da Gao, Min Xie, Jane Liu, Tijian Wang, Chaoqun Ma, Haokun Bai, Xing Chen, Mengmeng Li, Bingliang Zhuang, and Shu Li
Atmos. Chem. Phys., 21, 5847–5864,Short summary
O3 has been increasing in recent years over the Yangtze River Delta region of China and is closely associated with dominant weather systems. Still, the study on the impact of changes in synoptic weather patterns (SWPs) on O3 variation is quite limited. This work aims to reveal the unique features of changes in each SWP under O3 variation and quantifies the effects of meteorological conditions on O3 variation. Our findings could be helpful in strategy planning for O3 pollution control.
Alkuin Maximilian Koenig, Olivier Magand, Paolo Laj, Marcos Andrade, Isabel Moreno, Fernando Velarde, Grover Salvatierra, René Gutierrez, Luis Blacutt, Diego Aliaga, Thomas Reichler, Karine Sellegri, Olivier Laurent, Michel Ramonet, and Aurélien Dommergue
Atmos. Chem. Phys., 21, 3447–3472,Short summary
The environmental cycling of atmospheric mercury, a harmful global contaminant, is still not sufficiently constrained, partly due to missing data in remote regions. Here, we address this issue by presenting 20 months of atmospheric mercury measurements, sampled in the Bolivian Andes. We observe a significant seasonal pattern, whose key features we explore. Moreover, we deduce ratios to constrain South American biomass burning mercury emissions and the mercury uptake by the Amazon rainforest.
Yuming Jin, Ralph F. Keeling, Eric J. Morgan, Eric Ray, Nicholas C. Parazoo, and Britton B. Stephens
Atmos. Chem. Phys., 21, 217–238,Short summary
We propose a new atmospheric coordinate (Mθe) based on equivalent potential temperature (θe) but with mass as the unit. This coordinate is useful in studying the spatial and temporal distribution of long-lived chemical tracers (CO2, CH4, O2 / N2, etc.) from sparse data, like airborne observation. Using this coordinate and sparse airborne observation (HIPPO and ATom), we resolve the Northern Hemisphere mass-weighted average CO2 seasonal cycle with high accuracy.
Hossein Maazallahi, Julianne M. Fernandez, Malika Menoud, Daniel Zavala-Araiza, Zachary D. Weller, Stefan Schwietzke, Joseph C. von Fischer, Hugo Denier van der Gon, and Thomas Röckmann
Atmos. Chem. Phys., 20, 14717–14740,Short summary
Methane accounts for ∼ 25 % of current climate warming. The current lack of methane measurements is a barrier for tracking major sources, which are key for near-term climate mitigation. We use mobile measurements to identify and quantify methane emission sources in Utrecht (NL) and Hamburg (DE) with a focus on natural gas pipeline leaks. The measurements resulted in fixing the major leaks by the local utility, but coordinated efforts are needed at national levels for further emission reductions.
Chenchao Zhan, Min Xie, Chongwu Huang, Jane Liu, Tijian Wang, Meng Xu, Chaoqun Ma, Jianwei Yu, Yumeng Jiao, Mengmeng Li, Shu Li, Bingliang Zhuang, Ming Zhao, and Dongyang Nie
Atmos. Chem. Phys., 20, 13781–13799,Short summary
The Yangtze River Delta (YRD) region has been suffering from severe ozone (O3) pollution in recent years. Synoptic systems, like typhoons, can have a significant effect on O3 episodes. However, research on landfall typhoons affecting O3 in the YRD is limited. This work aims to reveal the main processes of landfall typhoons affecting surface O3 and estimate health impacts of O3 during the study period in the YRD, which can be useful for taking reasonable pollution control measures in this area.
José M. Esbrí, Pablo L. Higueras, Alba Martínez-Coronado, and Rocío Naharro
Atmos. Chem. Phys., 20, 12995–13010,Short summary
The aim of this work was to identify criteria to obtain the minimum amount of data with the maximum meaning and representativeness in order to delimit risk areas, both in a spatial and temporal respect. We have constructed a model of vertical mercury movements which could be used to predict the location and timing of mercury inhalation risk. Also, we have designed a monitoring strategy to identify the relevant criteria, which involved the measurement of gaseous mercury in a vertical section.
Alina Fiehn, Julian Kostinek, Maximilian Eckl, Theresa Klausner, Michał Gałkowski, Jinxuan Chen, Christoph Gerbig, Thomas Röckmann, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Pawel Jagoda, Norman Wildmann, Christian Mallaun, Rostyslav Bun, Anna-Leah Nickl, Patrick Jöckel, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 20, 12675–12695,Short summary
A severe reduction of greenhouse gas emissions is necessary to fulfill the Paris Agreement. We use aircraft- and ground-based in situ observations of trace gases and wind speed from two flights over the Upper Silesian Coal Basin, Poland, for independent emission estimation. The derived methane emission estimates are within the range of emission inventories, carbon dioxide estimates are in the lower range and carbon monoxide emission estimates are slightly higher than emission inventory values.
Flora Kluge, Tilman Hüneke, Matthias Knecht, Michael Lichtenstern, Meike Rotermund, Hans Schlager, Benjamin Schreiner, and Klaus Pfeilsticker
Atmos. Chem. Phys., 20, 12363–12389,Short summary
The presented study reports on airborne measurements of formaldehyde, glyoxal, methylglyoxal, and CO over the Amazon basin and lays a special focus on the influence of biomass burning emissions on the atmospheric profiles of these carbonyl compounds within the planetary boundary layer as well as in the free and upper troposphere.
Wei Wang, Laurens Ganzeveld, Samuel Rossabi, Jacques Hueber, and Detlev Helmig
Atmos. Chem. Phys., 20, 11287–11304,Short summary
Trees exchange with the atmosphere nitrogen oxides and ozone, affecting the tropospheric composition and consequently air quality and ecosystem health. We examined the leaf-level gas exchanges for four typical tree species (pine, maple, oak, aspen) found in northern Michigan, US. The leaves largely absorb the gases, showing little evidence of emission. We measured the uptake rates that can be used to improve model studies of the source and sink processes controlling these gases in forests.
Ingeborg Levin, Ute Karstens, Markus Eritt, Fabian Maier, Sabrina Arnold, Daniel Rzesanke, Samuel Hammer, Michel Ramonet, Gabriela Vítková, Sebastien Conil, Michal Heliasz, Dagmar Kubistin, and Matthias Lindauer
Atmos. Chem. Phys., 20, 11161–11180,Short summary
Based on observations and Stochastic Time-Inverted Lagrangian Transport (STILT) footprint modelling, a sampling strategy has been developed for tall tower stations of the Integrated Carbon Observation System (ICOS) research infrastructure atmospheric station network. This strategy allows independent quality control of in situ measurements, provides representative coverage of the influence area of the sites, and is capable of automated targeted sampling of fossil fuel CO2 emission hotspots.
Peter G. Simmonds, Matthew Rigby, Alistair J. Manning, Sunyoung Park, Kieran M. Stanley, Archie McCulloch, Stephan Henne, Francesco Graziosi, Michela Maione, Jgor Arduini, Stefan Reimann, Martin K. Vollmer, Jens Mühle, Simon O'Doherty, Dickon Young, Paul B. Krummel, Paul J. Fraser, Ray F. Weiss, Peter K. Salameh, Christina M. Harth, Mi-Kyung Park, Hyeri Park, Tim Arnold, Chris Rennick, L. Paul Steele, Blagoj Mitrevski, Ray H. J. Wang, and Ronald G. Prinn
Atmos. Chem. Phys., 20, 7271–7290,Short summary
Sulfur hexafluoride (SF6) is a potent greenhouse gas which is regulated under the Kyoto Protocol. From a 40-year record of measurements, collected at five global monitoring sites and archived air samples, we show that its concentration in the atmosphere has steadily increased. Using modelling techniques, we estimate that global emissions have increased by about 24 % over the past decade. We find that this increase is driven by the demand for SF6-insulated switchgear in developing countries.
Santiago Botía, Christoph Gerbig, Julia Marshall, Jost V. Lavric, David Walter, Christopher Pöhlker, Bruna Holanda, Gilberto Fisch, Alessandro Carioca de Araújo, Marta O. Sá, Paulo R. Teixeira, Angélica F. Resende, Cleo Q. Dias-Junior, Hella van Asperen, Pablo S. Oliveira, Michel Stefanello, and Otávio C. Acevedo
Atmos. Chem. Phys., 20, 6583–6606,Short summary
A long record of atmospheric methane concentrations in central Amazonia was analyzed. We describe events in which concentrations at 79 m are higher than at 4 m. These events are more frequent during the nighttime of dry season, but we found no association with fire signals. Instead, we suggest that a combination of nighttime transport and a nearby source could explain such events. Our research gives insights into how methane is transported in the complex nocturnal atmosphere in Amazonia.
Nikolay V. Balashov, Kenneth J. Davis, Natasha L. Miles, Thomas Lauvaux, Scott J. Richardson, Zachary R. Barkley, and Timothy A. Bonin
Atmos. Chem. Phys., 20, 4545–4559,Short summary
An accurate independent verification methodology to estimate methane (a powerful greenhouse gas) emissions is essential for the effective implementation of policies that aim to reduce the impacts of climate change. In this paper, four uncertainties that complicate the independent estimation of urban methane emissions are identified: the definition of urban domain, background heterogeneity, emissions temporal variability, and missing sources. Ways to improve emission estimates are suggested.
Jia Chen, Florian Dietrich, Hossein Maazallahi, Andreas Forstmaier, Dominik Winkler, Magdalena E. G. Hofmann, Hugo Denier van der Gon, and Thomas Röckmann
Atmos. Chem. Phys., 20, 3683–3696,Short summary
We demonstrate for the first time that large festivals can be significant methane sources, though they are not included in emission inventories. We combined in situ measurements with a Gaussian plume model to determine the Oktoberfest emissions and show that they are not due solely to human biogenic emissions, but are instead primarily fossil fuel related. Our study provides the foundation to develop reduction policies for such events and new pathways to mitigate fossil fuel methane emissions.
Pavlos Kalabokas, Niels Roland Jensen, Mauro Roveri, Jens Hjorth, Maxim Eremenko, Juan Cuesta, Gaëlle Dufour, Gilles Foret, and Matthias Beekmann
Atmos. Chem. Phys., 20, 1861–1885,Short summary
The influence of tropospheric ozone on the surface measurements at a regional air pollution station in the pre-Alpine area of northern Italy is investigated. During such episodes the local air pollution parameters show generally very low values, while the ozone levels reach high values, occasionally exceeding the ozone air quality standards. Better understanding of ozone variability over the examined region will help in the formulation of more effective policies for the environment and climate.
Han Han, Jane Liu, Lei Shu, Tijian Wang, and Huiling Yuan
Atmos. Chem. Phys., 20, 203–222,Short summary
We statistically assessed the impacts of local and synoptic meteorology on daily surface ozone in eastern China in summer during 2013–2018. The results show that the meteorology described by a multiple linear regression model explains 43 % of variations in surface ozone. The most important local meteorological factors vary with location in eastern China. The maximum impact of the predominant synoptic pattern on surface ozone can reach ± 8 µg m-3 or ± 16 % of the daily mean over some regions.
Roger J. Francey, Jorgen S. Frederiksen, L. Paul Steele, and Ray L. Langenfelds
Atmos. Chem. Phys., 19, 14741–14754,Short summary
25-year composites of interhemispheric baseline CO2 differences demonstrate close agreement between 4 monitoring networks. Variability from monthly to multiyear time frames mostly reflects variability in upper troposphere dynamical indices chosen to represent eddy and mean transport interhemispheric exchange. Monthly interhemispheric atmospheric fluxes are much larger than air–surface terrestrial exchanges. The composite differences offer unusual constraints on transport in global carbon models.
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Surface ozone concentrations in Mexico City frequently exceed the Mexican standard and have proven difficult to forecast due to changes in meteorological conditions at its tropical location. The Madden–Julian Oscillation (MJO) is largely responsible for intraseasonal variability in the tropics. Surface ozone in Mexico City is modulated by the MJO through its circulation pattern in the upper troposphere and its associated cloudiness, thus modulating solar radiation reaching the boundary layer.
Surface ozone concentrations in Mexico City frequently exceed the Mexican standard and have...