Articles | Volume 12, issue 18
https://doi.org/10.5194/acp-12-8475-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-12-8475-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Seasonal and annual variation of carbon dioxide surface fluxes in Helsinki, Finland, in 2006–2010
L. Järvi
Department of Physics, University of Helsinki, P.O. Box. 48, University of Helsinki, Finland
A. Nordbo
Department of Physics, University of Helsinki, P.O. Box. 48, University of Helsinki, Finland
H. Junninen
Department of Physics, University of Helsinki, P.O. Box. 48, University of Helsinki, Finland
A. Riikonen
Department of Forest Sciences, University of Helsinki, P.O. Box 27, University of Helsinki, Finland
J. Moilanen
Department of Physics, University of Helsinki, P.O. Box. 48, University of Helsinki, Finland
E. Nikinmaa
Department of Forest Sciences, University of Helsinki, P.O. Box 27, University of Helsinki, Finland
T. Vesala
Department of Physics, University of Helsinki, P.O. Box. 48, University of Helsinki, Finland
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Atmospheric NH3 in urban Beijing: long-term variations and implications for secondary inorganic aerosol control
How rainfall events modify trace gas mixing ratios in central Amazonia
Uncertainty in continuous ΔCO-based ΔffCO2 estimates derived from 14C flask and bottom-up ΔCO ∕ ΔffCO2 ratios
Dynamical drivers of free-tropospheric ozone increases over equatorial Southeast Asia
Air mass transport to the tropical western Pacific troposphere inferred from ozone and relative humidity balloon observations above Palau
Mixing-layer-height-referenced ozone vertical distribution in the lower troposphere of Chinese megacities: stratification, classification, and meteorological and photochemical mechanisms
Six years of continuous carbon isotope composition measurements of methane in Heidelberg (Germany) – a study of source contributions and comparison to emission inventories
What caused large ozone variabilities in three megacity clusters in eastern China during 2015–2020?
Atmospheric turbulence observed during a fuel-bed-scale low-intensity surface fire
Interannual variations in the Δ(17O) signature of atmospheric CO2 at two mid-latitude sites suggest a close link to stratosphere-troposphere exchange
Fingerprints of the COVID-19 economic downturn and recovery on ozone anomalies at high-elevation sites in North America and western Europe
Ozone in the boreal forest in the Alberta Oil Sands Region
Zugspitze ozone 1970–2020: the role of stratosphere–troposphere transport
High sulfur dioxide deposition velocities measured with the flux–gradient technique in a boreal forest in the Alberta Oil Sands Region
Quantification of methane emissions in Hamburg using a network of FTIR spectrometers and an inverse modeling approach
Local-to-regional methane emissions from the Upper Silesian Coal Basin (USCB) quantified using UAV-based atmospheric measurements
Transport pathways of carbon monoxide from Indonesian fire pollution to a subtropical high-altitude mountain site in the western North Pacific
Global warming will largely increase waste treatment CH4 emissions in Chinese megacities: insight from the first city-scale CH4 concentration observation network in Hangzhou, China
Disentangling methane and carbon dioxide sources and transport across the Russian Arctic from aircraft measurements
Airborne glyoxal measurements in the marine and continental atmosphere: comparison with TROPOMI observations and EMAC simulations
Mercury in the free troposphere and bidirectional atmosphere–vegetation exchanges – insights from Maïdo mountain observatory in the Southern Hemisphere tropics
Diurnal variability of atmospheric O2, CO2, and their exchange ratio above a boreal forest in southern Finland
How 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 2006–2019
Factors influencing the temporal variability of atmospheric methane emissions from Upper Silesia coal mines: a case study from the CoMet mission
Enhanced natural releases of mercury in response to the reduction in anthropogenic emissions during the COVID-19 lockdown by explainable machine learning
Temporal variability of tropospheric ozone and ozone profiles in the Korean Peninsula during the East Asian summer monsoon: insights from multiple measurements and reanalysis datasets
Retrieving CH4-emission rates from coal mine ventilation shafts using UAV-based AirCore observations and the genetic algorithm–interior point penalty function (GA-IPPF) model
Measurement report: Atmospheric mercury in a coastal city of Southeast China – inter-annual variations and influencing factors
Tropospheric 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 campaign
Transport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convection
Observational constraints on methane emissions from Polish coal mines using a ground-based remote sensing network
Continuous CH4 and δ13CH4 measurements in London demonstrate under-reported natural gas leakage
Long-term fluxes of carbonyl sulfide and their seasonality and interannual variability in a boreal forest
Declines and peaks in NO2 pollution during the multiple waves of the COVID-19 pandemic in the New York metropolitan area
Measurement report: Characterization of uncertainties in fluxes and fuel sulfur content from ship emissions in the Baltic Sea
Limitations of the radon tracer method (RTM) to estimate regional greenhouse gas (GHG) emissions – a case study for methane in Heidelberg
Positive and negative influences of typhoons on tropospheric ozone over southern China
Spatial and temporal variations of CO2 mole fractions observed at Beijing, Xianghe, and Xinglong in North China
The CO2 integral emission by the megacity of St Petersburg as quantified from ground-based FTIR measurements combined with dispersion modelling
Anthropogenic and natural controls on atmospheric δ13C-CO2 variations in the Yangtze River delta: insights from a carbon isotope modeling framework
Quantifying variability, source, and transport of CO in the urban areas over the Himalayas and Tibetan Plateau
New methodology shows short atmospheric lifetimes of oxidized sulfur and nitrogen due to dry deposition
Uncertainties in eddy covariance air–sea CO2 flux measurements and implications for gas transfer velocity parameterisations
Convergent evidence for the pervasive but limited contribution of biomass burning to atmospheric ammonia in peninsular Southeast Asia
Concurrent variation in oil and gas methane emissions and oil price during the COVID-19 pandemic
Ozone variability induced by synoptic weather patterns in warm seasons of 2014–2018 over the Yangtze River Delta region, China
Seasonal patterns of atmospheric mercury in tropical South America as inferred by a continuous total gaseous mercury record at Chacaltaya station (5240 m) in Bolivia
A mass-weighted isentropic coordinate for mapping chemical tracers and computing atmospheric inventories
Ziru Lan, Xiaoyi Zhang, Weili Lin, Xiaobin Xu, Zhiqiang Ma, Jun Jin, Lingyan Wu, and Yangmei Zhang
Atmos. Chem. Phys., 24, 9355–9368, https://doi.org/10.5194/acp-24-9355-2024, https://doi.org/10.5194/acp-24-9355-2024, 2024
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Our study examined the long-term trends of atmospheric ammonia in urban Beijing from 2009 to 2020. We found that the trends did not match satellite data or emission estimates, revealing complexities in ammonia sources. While seasonal variations in ammonia were temperature-dependent, daily variations were correlated with water vapor. We also found an increasing contribution of ammonia reduction, emphasizing its importance in mitigating the effects of fine particulate matter in Beijing.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
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Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Fabian Maier, Ingeborg Levin, Sébastien Conil, Maksym Gachkivskyi, Hugo Denier van der Gon, and Samuel Hammer
Atmos. Chem. Phys., 24, 8205–8223, https://doi.org/10.5194/acp-24-8205-2024, https://doi.org/10.5194/acp-24-8205-2024, 2024
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We assess the uncertainty in continuous fossil fuel carbon dioxide (ffCO2) estimates derived from carbon monoxide (CO) observations and radiocarbon (14CO2) flask measurements from an urban and a rural site. This study provides the basis for using continuous CO-based ffCO2 observations in atmospheric transport inversion frameworks to derive ffCO2 emission estimates. We also compare the flask-based CO / ffCO2 ratios with modeled ratios to validate an emission inventory for central Europe.
Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Ninong Komala, Habib Khirzin Al-Ghazali, Dian Yudha Risdianto, Ambun Dindang, Ahmad Fairudz bin Jamaluddin, Mohan Kumar Sammathuria, Norazura Binti Zakaria, Bryan J. Johnson, and Patrick D. Cullis
Atmos. Chem. Phys., 24, 5221–5234, https://doi.org/10.5194/acp-24-5221-2024, https://doi.org/10.5194/acp-24-5221-2024, 2024
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SHADOZ balloon-borne ozone measurements over equatorial Southeast Asia from 1998–2022 reveal that ozone increases during the early months of the year are linked to reduced convective storm activity, which typically redistributes and cleans the atmosphere of ozone. These findings challenge models to replicate the trends produced by the SHADOZ and meteorological observations and emphasize the importance of studying monthly or seasonal instead of annual changes for understanding ozone trends.
Katrin Müller, Peter von der Gathen, and Markus Rex
Atmos. Chem. Phys., 24, 4693–4716, https://doi.org/10.5194/acp-24-4693-2024, https://doi.org/10.5194/acp-24-4693-2024, 2024
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The transport history of tropospheric air masses above the tropical western Pacific is studied by local ozone and relative humidity profile measurements from Palau. A prominent anti-correlation between both tracers separates air masses of different origin and genesis. Back trajectories confirm a local convective origin of the year-round humid ozone-poor background. Anomalously dry ozone-rich air is generated in tropical Asia by pollution and dehydrated during transport via radiative cooling.
Zhiheng Liao, Meng Gao, Jinqiang Zhang, Jiaren Sun, Jiannong Quan, Xingcan Jia, Yubing Pan, and Shaojia Fan
Atmos. Chem. Phys., 24, 3541–3557, https://doi.org/10.5194/acp-24-3541-2024, https://doi.org/10.5194/acp-24-3541-2024, 2024
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This study collected 1897 ozonesondes from two Chinese megacities (Beijing and Hong Kong) in 2000–2022 to investigate the climatological vertical heterogeneity of lower-tropospheric ozone distribution with a mixing-layer-height-referenced (h-referenced) vertical coordinate system. This vertical coordinate system highlighted O3 stratification features existing at the mixing layer–free troposphere interface and provided a better understanding of O3 pollution in urban regions.
Antje Hoheisel and Martina Schmidt
Atmos. Chem. Phys., 24, 2951–2969, https://doi.org/10.5194/acp-24-2951-2024, https://doi.org/10.5194/acp-24-2951-2024, 2024
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In Heidelberg, Germany, methane and its stable carbon isotope composition have been measured continuously with a cavity ring-down spectroscopy (CRDS) analyser since April 2014. These 6-year time series are analysed with the Keeling plot method for the isotopic composition of the sources, as well as seasonal variations and trends in methane emissions. The source contributions derived from atmospheric measurements were used to evaluate global and regional emission inventories of methane.
Tingting Hu, Yu Lin, Run Liu, Yuepeng Xu, Shanshan Ouyang, Boguang Wang, Yuanhang Zhang, and Shaw Chen Liu
Atmos. Chem. Phys., 24, 1607–1626, https://doi.org/10.5194/acp-24-1607-2024, https://doi.org/10.5194/acp-24-1607-2024, 2024
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We hypothesize that the cause of the worsening O3 trends in the Beijing–Tianjin–Hebei region, the Yangtze River Delta, and Pearl River Delta from 2015 to 2020 is attributable to the increased occurrence of meteorological conditions of high solar radiation and a positive temperature anomaly under the influence of West Pacific subtropical high, tropical cyclones, and mid–high-latitude wave activities.
Joseph Seitz, Shiyuan Zhong, Joseph J. Charney, Warren E. Heilman, Kenneth L. Clark, Xindi Bian, Nicholas S. Skowronski, Michael R. Gallagher, Matthew Patterson, Jason Cole, Michael T. Kiefer, Rory Hadden, and Eric Mueller
Atmos. Chem. Phys., 24, 1119–1142, https://doi.org/10.5194/acp-24-1119-2024, https://doi.org/10.5194/acp-24-1119-2024, 2024
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Atmospheric turbulence affects wildland fire behaviors and heat and smoke transfer. Turbulence data collected during an experimental fire on a 10 m x 10 m densely instrumented burn plot are analyzed, and the results reveal substantial heterogeneity in fire-induced turbulence characteristics across the small plot, which highlights the necessity for coupled atmosphere–fire behavior models to have 1–2 m grid spacing so that adequate simulations of fire behavior and smoke transfer can be achieved.
Pharahilda M. Steur, Hubertus A. Scheeren, Gerbrand Koren, Getachew A. Adnew, Wouter Peters, and Harro A. J. Meijer
EGUsphere, https://doi.org/10.5194/egusphere-2023-2924, https://doi.org/10.5194/egusphere-2023-2924, 2024
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We present records of the triple oxygen isotope signature (Δ(17O)) of atmospheric CO2 conducted with laser absorption spectroscopy from two mid-latitude stations. Significant interannual variability is observed in both records. A model sensitivity study suggests that stratosphere-troposphere exchange, carrying high Δ(17O) CO2 from the stratosphere into the troposphere, causes most of the variability. This makes Δ(17O) a potential tracer for stratospheric intrusions in the troposphere.
Davide Putero, Paolo Cristofanelli, Kai-Lan Chang, Gaëlle Dufour, Gregory Beachley, Cédric Couret, Peter Effertz, Daniel A. Jaffe, Dagmar Kubistin, Jason Lynch, Irina Petropavlovskikh, Melissa Puchalski, Timothy Sharac, Barkley C. Sive, Martin Steinbacher, Carlos Torres, and Owen R. Cooper
Atmos. Chem. Phys., 23, 15693–15709, https://doi.org/10.5194/acp-23-15693-2023, https://doi.org/10.5194/acp-23-15693-2023, 2023
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We investigated the impact of societal restriction measures during the COVID-19 pandemic on surface ozone at 41 high-elevation sites worldwide. Negative ozone anomalies were observed for spring and summer 2020 for all of the regions considered. In 2021, negative anomalies continued for Europe and partially for the eastern US, while western US sites showed positive anomalies due to wildfires. IASI satellite data and the Carbon Monitor supported emission reductions as a cause of the anomalies.
Xuanyi Zhang, Mark Gordon, Paul A. Makar, Timothy Jiang, Jonathan Davies, and David Tarasick
Atmos. Chem. Phys., 23, 13647–13664, https://doi.org/10.5194/acp-23-13647-2023, https://doi.org/10.5194/acp-23-13647-2023, 2023
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Measurements of ozone in the atmosphere were made in a forest downwind of oil sands mining and production facilities in northern Alberta. These measurements show that the emissions of other pollutants from oil sands production and processing reduce the amount of ozone in the forest. By using an atmospheric model combined with measurements, we find that the rate at which ozone is absorbed by the forest is lower than typical rates from similar measurements in other forests.
Thomas Trickl, Cédric Couret, Ludwig Ries, and Hannes Vogelmann
Atmos. Chem. Phys., 23, 8403–8427, https://doi.org/10.5194/acp-23-8403-2023, https://doi.org/10.5194/acp-23-8403-2023, 2023
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Downward atmospheric transport from the stratosphere (STT) is the most important natural source of tropospheric ozone. We analyse the stratospheric influence on the long-term series of ozone and carbon monoxide measured on the Zugspitze in the Bavarian Alps (2962 m a.s.l.). Since the 1970s, there has been a pronounced ozone rise that has been ascribed to an increase in STT. We determine the stratospheric influence from the observational data alone (humidity and 7Be).
Mark Gordon, Dane Blanchard, Timothy Jiang, Paul A. Makar, Ralf M. Staebler, Julian Aherne, Cris Mihele, and Xuanyi Zhang
Atmos. Chem. Phys., 23, 7241–7255, https://doi.org/10.5194/acp-23-7241-2023, https://doi.org/10.5194/acp-23-7241-2023, 2023
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Measurements of the gas sulfur dioxide (SO2) were made in a forest downwind of oil sands mining and production facilities in northern Alberta. These measurements tell us the rate at which SO2 is absorbed by the forest. The measured rate is much higher than what is currently used by air quality models, which is supported by a previous study in this region. This suggests that SO2 may have a much shorter lifetime in the atmosphere at this location than currently predicted by models.
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., 23, 6897–6922, https://doi.org/10.5194/acp-23-6897-2023, https://doi.org/10.5194/acp-23-6897-2023, 2023
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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 Hamburg. Multiple sources that contribute to methane emissions were located and quantified. Methane sources were found to be mainly caused by human activity (e.g., by release from oil and gas refineries). Moreover, potential natural sources have been located, such as the Elbe River and lakes.
Truls Andersen, Zhao Zhao, Marcel de Vries, Jaroslaw Necki, Justyna Swolkien, Malika Menoud, Thomas Röckmann, Anke Roiger, Andreas Fix, Wouter Peters, and Huilin Chen
Atmos. Chem. Phys., 23, 5191–5216, https://doi.org/10.5194/acp-23-5191-2023, https://doi.org/10.5194/acp-23-5191-2023, 2023
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The Upper Silesian Coal Basin, Poland, is one of the hot spots of methane emissions in Europe. Using an uncrewed 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.
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, https://doi.org/10.5194/acp-23-4727-2023, https://doi.org/10.5194/acp-23-4727-2023, 2023
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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, https://doi.org/10.5194/acp-23-4501-2023, https://doi.org/10.5194/acp-23-4501-2023, 2023
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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, https://doi.org/10.5194/acp-23-2293-2023, https://doi.org/10.5194/acp-23-2293-2023, 2023
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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, https://doi.org/10.5194/acp-23-1369-2023, https://doi.org/10.5194/acp-23-1369-2023, 2023
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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, https://doi.org/10.5194/acp-23-1309-2023, https://doi.org/10.5194/acp-23-1309-2023, 2023
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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, https://doi.org/10.5194/acp-23-851-2023, https://doi.org/10.5194/acp-23-851-2023, 2023
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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, https://doi.org/10.5194/acp-23-725-2023, https://doi.org/10.5194/acp-23-725-2023, 2023
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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, https://doi.org/10.5194/acp-23-453-2023, https://doi.org/10.5194/acp-23-453-2023, 2023
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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, https://doi.org/10.5194/acp-22-16031-2022, https://doi.org/10.5194/acp-22-16031-2022, 2022
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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, https://doi.org/10.5194/acp-22-15851-2022, https://doi.org/10.5194/acp-22-15851-2022, 2022
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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.
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, https://doi.org/10.5194/acp-22-14177-2022, https://doi.org/10.5194/acp-22-14177-2022, 2022
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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, https://doi.org/10.5194/acp-22-13881-2022, https://doi.org/10.5194/acp-22-13881-2022, 2022
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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, https://doi.org/10.5194/acp-22-11187-2022, https://doi.org/10.5194/acp-22-11187-2022, 2022
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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, https://doi.org/10.5194/acp-22-11137-2022, https://doi.org/10.5194/acp-22-11137-2022, 2022
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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, https://doi.org/10.5194/acp-22-10703-2022, https://doi.org/10.5194/acp-22-10703-2022, 2022
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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, https://doi.org/10.5194/acp-22-8221-2022, https://doi.org/10.5194/acp-22-8221-2022, 2022
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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, https://doi.org/10.5194/acp-22-5859-2022, https://doi.org/10.5194/acp-22-5859-2022, 2022
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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, https://doi.org/10.5194/acp-22-3595-2022, https://doi.org/10.5194/acp-22-3595-2022, 2022
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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, https://doi.org/10.5194/acp-22-2569-2022, https://doi.org/10.5194/acp-22-2569-2022, 2022
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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, https://doi.org/10.5194/acp-22-2399-2022, https://doi.org/10.5194/acp-22-2399-2022, 2022
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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.
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, https://doi.org/10.5194/acp-21-18175-2021, https://doi.org/10.5194/acp-21-18175-2021, 2021
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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, https://doi.org/10.5194/acp-21-17907-2021, https://doi.org/10.5194/acp-21-17907-2021, 2021
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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, https://doi.org/10.5194/acp-21-16911-2021, https://doi.org/10.5194/acp-21-16911-2021, 2021
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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, https://doi.org/10.5194/acp-21-11741-2021, https://doi.org/10.5194/acp-21-11741-2021, 2021
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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, https://doi.org/10.5194/acp-21-10939-2021, https://doi.org/10.5194/acp-21-10939-2021, 2021
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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, https://doi.org/10.5194/acp-21-10015-2021, https://doi.org/10.5194/acp-21-10015-2021, 2021
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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, https://doi.org/10.5194/acp-21-9201-2021, https://doi.org/10.5194/acp-21-9201-2021, 2021
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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, https://doi.org/10.5194/acp-21-8377-2021, https://doi.org/10.5194/acp-21-8377-2021, 2021
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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, https://doi.org/10.5194/acp-21-8089-2021, https://doi.org/10.5194/acp-21-8089-2021, 2021
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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, https://doi.org/10.5194/acp-21-7187-2021, https://doi.org/10.5194/acp-21-7187-2021, 2021
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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, https://doi.org/10.5194/acp-21-6605-2021, https://doi.org/10.5194/acp-21-6605-2021, 2021
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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, https://doi.org/10.5194/acp-21-5847-2021, https://doi.org/10.5194/acp-21-5847-2021, 2021
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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, https://doi.org/10.5194/acp-21-3447-2021, https://doi.org/10.5194/acp-21-3447-2021, 2021
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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, https://doi.org/10.5194/acp-21-217-2021, https://doi.org/10.5194/acp-21-217-2021, 2021
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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.
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