AS3.19 | Atmospheric composition variability and trends
EDI PICO
Atmospheric composition variability and trends
Convener: Oksana Tarasova | Co-conveners: Andrea Pozzer, Bin QuECSECS, Euan Nisbet, Pedro Jimenez-Guerrero
PICO
| Fri, 19 Apr, 08:30–12:30 (CEST)
 
PICO spot 5
Fri, 08:30
The session focuses on the variability of the tropospheric and stratospheric chemical composition on the timescales from diurnal to decadal. It discusses the processes driving this variability and attribution of changes to specific drivers. Special emphasis is put on the value of high-quality long-term measurement data sets both from scientific and societal perspective and their sustainability. Supporting model simulations on different scales that utilize observational data will also be discussed. Contributions related to emerging constituents, new data sources and approached to atmospheric composition monitoring (e.g. low cost sensor, emerging measurement techniques), measurement campaign that addresses specific processes and long-term projections of the atmospheric chemical composition are also welcome in the session. The presentations that address policy-relevant datasets on atmospheric composition are cordially invited.
Researchers are invited to present novel scientific results from mid- and long-term observational time series from various programmes and networks such as the Global Atmosphere Watch (GAW) Programme, European Monitoring, and Evaluation Programme (EMEP), Network for the Detection of Atmospheric Composition Change (NDACC), Southern Hemisphere Additional Ozonesondes (SHADOZ), Advanced Global Atmospheric Gases Experiment (AGAGE), National Oceanic and Atmospheric Administration (NOAA), regular airborne (e.g. CARIBIC, IAGOS, CONTRAIL) and other campaigns as well as satellite data and model simulations. Data relevant to tropospheric and stratospheric composition, in particular, related to ozone depletion, climate change, and air quality as well as firn data on past atmospheric composition are welcome. We welcome contributions from multi-year modeling studies and inter-comparison exercises that address past and future tropospheric or stratospheric composition changes, carried out in the framework of international projects and initiatives.

PICO: Fri, 19 Apr | PICO spot 5

Chairperson: Oksana Tarasova
08:30–08:32
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PICO5.1
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EGU24-470
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ECS
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On-site presentation
Evolution of Ozone above Togo during the 1979–2020 Period
(withdrawn after no-show)
Koffi Ayassou, Andrea Pazmiño, Kokou Sabi, Ariane Bazureau, and Sophie Godin-Beekmann
08:32–08:34
|
PICO5.2
|
EGU24-20001
|
On-site presentation
Paul Griffiths, James Keeble, and Luke Abraham

The transport of ozone from the stratosphere to the troposphere is a key contributor to the tropospheric ozone budget. It is estimated that the stratosphere-to-troposphere flux of ozone (STT) leads to ~500 Tg of ozone transported into the troposphere each year, which is comparable to the net chemical production of ozone within the troposphere. 

We will present an analysis of the tropospheric ozone budget in the CCMI2022 experiments performed with UKESM-StratTrop, a whole atmosphere chemistry-climate model. 

We focus on the specified dynamics experiments covering 1982-2018, during which there was significant ozone depletion.  We intercompare the ozone budget from the derived using the complementary approaches of Ox and Oy species, and use idealised tracers to examine in detail the role of stratosphere-to-troposphere transport on tropospheric composition.  Where possible, these model simulations are compared with in-situ calculation of ozone production and loss rates derived from observations.

How to cite: Griffiths, P., Keeble, J., and Abraham, L.: Analysis of UKESM1-StratTrop CCMI2022 experiments with a focus on ozone trends, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-20001, https://doi.org/10.5194/egusphere-egu24-20001, 2024.

08:34–08:36
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PICO5.3
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EGU24-19728
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ECS
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On-site presentation
Hao Fu, Yao Té, Christof Janssen, Pascal Jeseck, Corinne Boursier, Patrick Marie-Jeanne, and Christian Rouille

The European megacity of Paris with 11 million habitants provides a unique research platform for atmospheric science. Since 2011, our group has continuously operated a high-resolution Fourier-transform infrared spectrometer (FTS-Paris) for the study of atmospheric composition above Paris. The measurements cover alternatively the near-infrared spectral domain related to the TCCON[1] network (since 2014) and the thermal infrared related to NDACC-IRWG[2] network. So far, there has been limited research into the origins of air masses over Paris. However, understanding the dynamics of the air masses over Paris is crucial for comprehending and studying the city’s atmospheric composition. Consequently, we have studied the seasonal variability of the air mass passing through Paris in the period 2011 to 2020 by using the Hybrid Single-Particle Lagrangian Integrated Trajectory (Hysplit) model. Furthermore, we combined our NDACC-IRWG measurement data with simulated trajectories from Hysplit to investigate the characteristics of the potential source of the specific trace gases by applying Weighted Potential Source Contribution Function (WPSCF). The results illustrated that the air masses above Paris were predominantly contributed from the west the north, while the eastern sector, despite its minor contribution, emerged as a significant source of the specific trace gases from the WPSCF results.


[1] Total Carbon Column Observation Network

[2]Network for Detection of Atmospheric Composition Change – Infrared Working Group

How to cite: Fu, H., Té, Y., Janssen, C., Jeseck, P., Boursier, C., Marie-Jeanne, P., and Rouille, C.: Ten-year air masses contribution study and potential source of specific components in Paris, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19728, https://doi.org/10.5194/egusphere-egu24-19728, 2024.

08:36–08:38
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PICO5.4
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EGU24-2664
|
ECS
|
On-site presentation
Zheng Li, Xiaocheng Wu, Junfeng Yang, Cui Tu, Xiong Hu, and Zhaoai Yan

The stellar occultation technique detects Earth’s atmospheric components by measuring the absorption of the stellar spectrum. In this paper, A method of air density retrieval using stellar occultation transmission data in oxygen absorption A band is studied. In this method, the average single-band transmission in oxygen A-band is used to calculate the effective optical depth of each layer of atmosphere by using the peeling onion algorithm. Then, the effective optical depth of each layer and prior atmospheric temperature data are used to obtain the oxygen number density profile by using the retrieval method. Finally, the stable proportion of oxygen in the atmosphere is taken into account. By introducing the iterative algorithm of atmospheric static equilibrium and ideal gas state equation, the accuracy of air density retrieval is improved under the condition of deviation of prior temperature. The results of simulation retrieval are presented in this paper. This method overcomes the negative influence of prior temperature deviation on the retrieval accuracy, and provides a new method and theoretical basis for stellar occultation detection and air density detection.

How to cite: Li, Z., Wu, X., Yang, J., Tu, C., Hu, X., and Yan, Z.: The Iteration Method for Air Density Retrieval in The Stellar Occultation Measurement, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2664, https://doi.org/10.5194/egusphere-egu24-2664, 2024.

08:38–08:40
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PICO5.5
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EGU24-14152
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On-site presentation
David Flittner, Marilee Roell, Robbert Manion, and Kevin Leavor

After completion of the robot installation on the International Space Station (ISS) in early March 2017 as an external hosted science payload, the Stratospheric Aerosol and Gas Experiment (SAGE) III became the newest member to the family of space-based solar occultation instruments operated by NASA to investigate the Earth’s upper atmosphere since the late 1970s. One of three identical instruments, the SAGE III/ISS mission was revived in the early 2010s with a primary objective to monitor the vertical distribution of aerosol, ozone and other trace gases to enhance understanding of ozone recovery and climate change processes in the upper atmosphere. The 51.6-degree inclined orbit of the ISS is well-suited for solar occultation and provides near-global observations on a monthly basis with coverage of low and mid-latitudes similar to that of the SAGE II mission, which operated over two decades – outliving its platform.  International commitment to continuing ISS as a science outpost throughout this decade enables SAGE III to serve as a bridge to future stratospheric composition missions.

The nominal science products, derived from sampling spectra covering 290nm to 1030nm and a photo-diode near 1550 nm, include high resolution vertical profiles of ozone, nitrogen dioxide and water vapor, along with multi-wavelength aerosol extinction. Although in the visible portion of the spectrum the brightness of the Sun is a million times that of the full Moon, the SAGE III instrument design covers this large dynamic range, performing lunar occultations on a routine basis to augment the solar products. The standard lunar products include ozone and nitrogen trioxide. Routine observations began June 2017 and continue to the present. This has enabled observations of significant perturbations of the stratosphere induced by multiple episodic terrestrial events - wildfires (two of which were record setting) and volcanic eruptions - and dynamical forcings such as phase changes of the Quasi-Biennial Oscillation (QBO).  Here is presented stratospheric variability as represented in the standard SAGE III/ISS data products since 2017.  The stability of observations afforded by the solar occultation technique is superb for quantifying long-term changes in stratospheric composition.  Thus, comparisons with variability recorded by previous SAGE missions are also shown. 

How to cite: Flittner, D., Roell, M., Manion, R., and Leavor, K.: Stratospheric composition variability observed from the International Space Station (ISS) by the Stratospheric Aerosol and Gas Experiment III (SAGE III/ISS), EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14152, https://doi.org/10.5194/egusphere-egu24-14152, 2024.

08:40–08:42
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EGU24-14286
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Virtual presentation
Jeremie Lasue, Anni Määttänen, Michael Zolensky, François Ravetta, and Augustin Grunewald

The life cycle of a spacecraft starts and ends in the atmosphere: it interacts with the atmosphere right after the launch and during the atmospheric reentry when it usually mostly ablates. Both phases induce emissions of gases and solid particles, providing a source of these components in the middle atmosphere. Little is known about the exact nature, composition and effects of these emissions on the atmosphere and climate, but their impact is expected to rise as more and more orbiting satellites are launched. Ever since the years 2000, the number of space rockets launched per year has increased by a factor 3 globally. At the same time, the number of satellites launched in orbit around the Earth per year has been multiplied by about 30. One may wonder whether changes in the anthropogenic material injected in the terrestrial stratosphere can be detected and what its influence may be. 

In order to study the cosmic dust particles arriving on Earth, the NASA Johnson Space Center (JSC) has been systematically collecting solid dust particles from the Earth’s stratosphere by aircraft equipped with dedicated particle collectors since 1981. So far, 25 catalogs have been published, covering campaigns of collection from 1981 to 2020, with a total of 5071 solid particles that have been preliminary characterized and curated. In this work, we use the preliminary classification of the dust particles. Based on SEM images and X-ray EDS composition the collected dust is separated into four groups: C (Cosmic), TCN (Terrestrial Contaminant Natural), TCA (Terrestrial Contaminant Artificial) and AOS (Aluminum Oxide Sphere). The AOS being mostly generated by solid rocket propellant, they also belong to the TCA class. Our analysis of the data published indicates that from 1980 to 2009 the cosmic dust particles typically represent on average 40% of the collection with TCA and TCN corresponding to about 30% each. In the recent years, the TCA fraction has doubled to about 60% of the collection (2010-2020). This increase in anthropogenic particles is likely due to the overall human space activity and its recent increase. We will present the properties of the solid stratospheric dust particles collected and their evolution with time.

Future work will be dedicated to better classify the natural and anthropogenic particles collected and described in the existing databases. We will use numerical modelling to produce quantitative estimates of the injected mass, the lifetime of particles in the middle atmosphere (stratosphere) and the relative abundance of the anthropogenic particles with respect to the stratospheric background particle population.

How to cite: Lasue, J., Määttänen, A., Zolensky, M., Ravetta, F., and Grunewald, A.: Assessing stratospheric aerosols contamination due to space activities, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14286, https://doi.org/10.5194/egusphere-egu24-14286, 2024.

08:42–08:44
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PICO5.7
|
EGU24-14600
|
On-site presentation
The STRAtosphere TO Surface (STRATOS) Mission: An Earth System Explorer Proposal to Study Long-Term Changes in the Stratosphere and Their Impacts at Earth's Surface 
(withdrawn)
Jessica Neu, Nathaniel Livesey, Marianna Linz, Bianca Baier, Arlene Fiore, Lorenzo Polvani, Kazuyuki Miyazaki, Louis Rivoire, Michelle Santee, Carl Percival, Luis Millan Valle, Goutam Chattopadhyay, Mark Chodas, and Valerie Scott
08:44–08:46
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PICO5.8
|
EGU24-1046
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ECS
|
On-site presentation
Statistical analysis of water vapour profiles over the ACTRIS AGORA station in Granada using Raman lidar 
(withdrawn)
Arlett Díaz Zurita, Daniel Pérez Ramírez, Inmaculada Foyo Moreno, Jose Antonio Benavent Oltra, Ana del Águila, Sol Fernández Carvelo, Juan Antonio Bravo Aranda, María José Granados Muñoz, Juan Luis Guerrero Rascado, Lucas Alados Arboledas, and Francisco Navas Guzmán
08:46–08:48
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PICO5.9
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EGU24-14910
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On-site presentation
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Constantina Rousogenous, Christof Petri, Thorsten Warneke, Pierre-Yves Quéhé, Thomas Laemmel, Michel Ramonet, Justus Notholt, Jean-Daniel Paris, Michail Vrekousis, and Jean Sciare

At the crossroads of Europe, Africa, and Asia, the island of Cyprus receives long-range and regional pollution from various anthropogenic and natural sources. To assess the variability and amounts of greenhouse gases (GHG) in the region, we have set up, in 2019, a new Total Carbon Column Observing Network (TCCON) site, the TCCON Nicosia, at The Cyprus Institute. Herewith, we present the first time series of columnar amounts of the main GHGs in the region (Xgas; X stands for total column average dry-air mole fractions), namely carbon dioxide (XCO2), methane (XCH4), nitrous oxide (XN2O), carbon monoxide (XCO) and hydrogen fluoride (XHF). To evaluate the performance of TCCON, an AirCore campaign was conducted in Cyprus in June 2020, providing independent in-situ vertical profiles of CO2, CH4 and CO extending up to the stratosphere. The recent observations of XGHG data, together with the results of the AirCore, are presented. The observed variability in the columnar time series and its possible drivers are discussed.

How to cite: Rousogenous, C., Petri, C., Warneke, T., Quéhé, P.-Y., Laemmel, T., Ramonet, M., Notholt, J., Paris, J.-D., Vrekousis, M., and Sciare, J.: Variability of Total Column CO2, CH4 and CO in the Eastern Mediterranean And Middle East (EMME) Region: Insights from the TCCON Nicosia and AirCore, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-14910, https://doi.org/10.5194/egusphere-egu24-14910, 2024.

08:48–08:50
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PICO5.10
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EGU24-19613
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On-site presentation
Stephen Montzka, Isaac Vimont, Bradley Hall, and Scott Clingan

Ethane-based chlorofluorocarbons and hydrochlorofluorocarbons can have multiple isomers that are difficult to separate using gas chromatography with detection by electron capture (GC-ECD) or even mass spectrometry (GC-MS). Examples include CFC-113 and CFC-113a; CFC-114 and CFC-114a; CFC-112 and CFC-112a; and HCFC-124 and HCFC-124a.  As a result, atmospheric histories reported in the past by most laboratories for the more abundant isomer can represent an ill-defined combination of both chemicals.  This is especially true for CFC-113 over the past decade, as mole fractions of CFC-113a have increased rapidly during that time and the contribution of this isomer to our understanding of atmospheric changes measured ostensibly for CFC-113 has not been known. Being able to accurately and routinely determine atmospheric abundances for each of these isomers separately from one another is important as these isomers have different environmental impacts (ozone-depleting potentials and global warming potentials) and different sources likely contribute to their emissions.  Here we demonstrate a technique for quantifying the abundances of co-eluting isomers using GC-MS even when ions unique to the different isomers are unavailable.  Initial results for CFC-113 and 113a will be presented that allow a reassessment of the atmospheric decline and global emission rate of CFC-113 over the past decade, and they confirm the rapid increases in the atmospheric abundance of CFC-113a.  Co-variations between the measured CFC-113a atmospheric mole fractions and other gases are observed at particular sites (e.g., Mauna Loa, Hawaii) that help identify regions where CFC-113a emissions are currently substantial, contributing to its rapid global increase.

How to cite: Montzka, S., Vimont, I., Hall, B., and Clingan, S.: Making atmospheric measurements of difficult-to-separate isomers of CFCs routine: a case study of CFC-113 and CFC-113a that refines our understanding of recent atmospheric changes for both of these chemicals., EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19613, https://doi.org/10.5194/egusphere-egu24-19613, 2024.

08:50–08:52
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PICO5.11
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EGU24-2540
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On-site presentation
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Vadim Rakitin, Andrey Skorokhod, Yury Shtabkin, Natalia Kirillova, and Eugenia Fedorova

Based on the analysis of orbital measurements and GEOS-Chem model calculations with different anthropogenic and wild-fires emission scenarios, a study of trends in the total content of CO and CH4 in different periods and seasons of 2003-2023 for the Eurasia domain, -20°E - 180°E, 0°N - 80°N. A response of CO trends to climate change was estimated. Data from the orbital AIRS instrument and ground-based spectrometers were used as experimental information to assess atmospheric composition trends.
A good agreement has been established between estimates obtained from the orbital data and from simulations. However, certain regional features of the discrepancies have been identified and are associated with the inaccuracy of specifying the spatial distribution and integral power of anthropogenic CO, CH4 and another species emission and their trends for Russia, South-East Asia and other regions of Eurasia. These emission uncertainties affect the accuracy of model calculations.
In general, according to average annual estimates, CO TC trends over entire Eurasia for 2000-2023 was slightly negative (~ 0.5-1.2 %/year depending on the region); however, after approximately 2008 the downward trend slowed down, and in some areas the CO TC began to rise.
Thus, a positive change in CO TC trends after about 2008 was established. In the entire domain under study, this change was about 2–3%/year, according both experimental and model estimates. In autumn months of 2008-2023 the increase in CO TC was established over almost the entire Eurasia, including Arctic regions and Europe. This growth (at least in Europe) cannot be explained by either anthropogenic emissions or releases from wild-fires. A possible reason for this rising may be the formation of additional CO from methane, the increase in concentrations of which began around the same time (after 2007), and change in the source/sink ratio for CO.
Additionally, to assess the parameters of correspondence between orbital and ground-based measurements, we have compared the trend estimates using only synchronous orbital and ground-based CO and CH4 observations and obtained the drift of the difference between them.
The study was supported by Russian Science Foundation under grant №20-17-00200.

How to cite: Rakitin, V., Skorokhod, A., Shtabkin, Y., Kirillova, N., and Fedorova, E.: Study of atmospheric CO and CH4 trends and their response on global climate changes based on experimental data and model simulations, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2540, https://doi.org/10.5194/egusphere-egu24-2540, 2024.

08:52–08:54
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PICO5.12
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EGU24-9742
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ECS
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On-site presentation
Lukas Heizmann, Mathias Palm, Justus Notholt, and Matthias Buschmann

The solar absorption spectroscopy has been established as a powerful tool to monitor the trace gas composition of the atmosphere and is used in world wide networks such as TCCON (Total Carbon Column Observing Network) and NDACC (Network for Detection of Atmospheric Composition Change). The solar absorption measurements have the disadvantage that in Arctic regions there are no measurements possible during polar night leading to significant gaps in the data record. To fill those gaps we deploy a Bruker Vertex 80 spectrometer in emission geometry at the AWIPEV station in Ny-Ålesund, Svalbard. For highest possible resolution of 0.08 cm⁻¹, one-sided interferograms are recorded. Total power calibration procedures with two reference black bodies developed for double-sided interferograms (having lower resolution) are adjusted to obtain radiometrically calibrated zenith viewing emission spectra. The optimal estimation method is used to retrieve atmospheric water vapor and methane for cloud-free scenes. Results are compared to radiosondes and TCCON measurements. We investigate in detail the influence of black body emissivity and temperature uncertainty as quality check of our setup. The importance of spectral resolution is tested to prepare our retrieval to work with other instruments such as the 1 cm⁻¹ resolution E-AERI deployed during the MOSAiC campaign.

How to cite: Heizmann, L., Palm, M., Notholt, J., and Buschmann, M.: Infrared emission spectroscopy for trace gas retrievals in the Arctic, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9742, https://doi.org/10.5194/egusphere-egu24-9742, 2024.

08:54–08:56
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PICO5.13
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EGU24-2565
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On-site presentation
|
Natalia Kirillova, Vadim Rakitin, Andrey Skorokhod, Anatoly Dzhola, Arseny Shilkin, and Eugeniya Fedorova

This report presents the results of a comprehensive analysis of spectroscopic long-term data sets on CO total content (CO TC) at stations of the A.M. Obukhov Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS), in Moscow and Moscow oblast. The long-term variability of CO TC and meteorological parameters in atmospheric boundary layer were investigated. A decrease in the average TC CO annual values in 2000–2023 was found for Moscow (–2.23 ± 0.36%/year) and for Zvenigorod Scientific Station (ZSS) (‒1.12 ± 0.33%/year). The CO trend characteristics in both sites in different seasons and periods are demonstrated and discussed.

After about 2007–2008, the rate of CO TC reduction decreased at both sites. In 2008–2023 at the ZSS no significant changes in CO TC in the summer and autumn months were found: trend was near zero (-0.04±0.81%/year). An increase in the wind speed in the atmospheric boundary layer of Moscow in different periods of 2008–2022 at a rate of 0.66±0.55%/year has been determined. At the same time, no statistically significant changes in wind speed were found in Kaluga oblast (0.12±0.56%/year). The results indicate the influence of the climatic (meteorological) factor on air quality in Moscow.

Study was supported by Russian Science Foundation, Project No 20-17-00200.

How to cite: Kirillova, N., Rakitin, V., Skorokhod, A., Dzhola, A., Shilkin, A., and Fedorova, E.: Long-Term Tendencies and Variability of CO content in the Atmosphereof the Moscow Megapolis, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2565, https://doi.org/10.5194/egusphere-egu24-2565, 2024.

08:56–08:58
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PICO5.14
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EGU24-18503
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On-site presentation
Pascale Chelin, Rebecca D. Kutzner, Juliette Brochet, Sylvain Caville, Mokhtar Ray, Xavier Landsheere, Juan Cuesta, Guillaume Siour, Yelva Roustan, Frank Hase, and Claude Camy-Peyret

Ammonia (NH3) has direct adverse effects on ecosystems and environment regarding the eutrophication and acidification of soils and water (Cape et al., 2009; Krupa, 2003). As the main alkaline molecule in the atmosphere, NH3 is also a gaseous precursor of other major secondary pollutants, such as inorganic fine particles: sulphate and ammonium nitrate particles (Seinfeld, and Pandis, 2006), which are very harmful to public health. Ammonia is an atmospheric pollutant mainly emitted by agricultural activities (e.g 80% of the emissions worldwide and 95% of the emissions in Europe) (Génermont et al., 2018; Skorupka and Nosalewicz, 2021) with part from traffic that is highly uncertain in urban areas (Cao et al., 2021). Ammonia emissions are projected to increase in the future due to population growth, rise in food demand and climate change.

Despite its environmental impacts, ammonia is one of the least documented precursors of PM2.5 in France which is strongly related to the crucial lack of routine ammonia observations. One of the scientific reasons comes from the difficulty to measure atmospheric ammonia in situ due to its polar, sticky, volatile, and highly water-soluble nature (von Bobrutzki et al., 2010) resulting in strong interactions with sampling systems, recently well documented during the French AMICA* campaign.

An innovative and very promising alternative for monitoring atmospheric ammonia is infrared remote sensing, from the ground or from space. The first multiyear time series of atmospheric NH3 ground-based measurements over a European megacity (Paris) was performed using Observations of the Atmosphere by Solar absorption Infrared Spectroscopy (OASIS) FTIR observatory, based on the NDACC stations’ methodology, and located in the Paris suburbs (France) (Tournadre et al., 2020). In this presentation, we test different a priori profiles and retrieval methods in order to investigate the robustness of the NH3-OASIS retrievals. We show the potential of the observatory to assess diurnal variability of ammonia focusing on spring pollution events such as in March 2012 (Kutzner et al., 2021) and compare the measured NH3-OASIS total columns to simulations from the CAMS data assimilation system (Inness et al., 2019).

 

*: AMICA consortium : Analysis of Multi-Instrumental Concentrations of Ammonia

References

Cape, J. N., et al., Environmental Pollution, 2009, 157(3), 1033–1037, https://doi.org/10.1016/j.envpol.2008.09.049

Krupa, S. V., Environmental Pollution, 2003, 124, Issue 2, 179–221, https://doi.org/10.1016/S0269-7491(02)00434-7

Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics: from Air Pollution to Climate Change, third ed., John Wiley & Sons, New York, 1121 pp., 2016

Génermont, S., et al., Data in Brief, 2018, 21, 1119–1124 https://doi.org/10.1016/j.dib.2018.09.119

Skorupka, M., and Nosalewicz, A., Agriculture, 2021, 11(9). https://doi.org/10.3390/agriculture11090822

Cao H., et al., Environmental Science & Technology Letters, 2022 9 (1), 3-9 https://doi.org/10.1021/acs.estlett.1c00730

von Bobrutzki, et al., Atmos. Meas. Tech., 2010, 3, 91–112, https://doi.org/10.5194/amt-3-91-2010

Tournadre, B., et al., Atmos. Meas. Tech., 13, 3923–3937, https://doi.org/10.5194/amt-13-3923-2020, 2020.

Kutzner, R. D., et al., Atmos. Chem. Phys., 21, 12091–12111, https://doi.org/10.5194/acp-21-12091-2021, 2021.

Inness, A., et al., Atmos. Chem. Phys., 19, 3515–3556, https://doi.org/10.5194/acp-19-3515-2019, 2019.

How to cite: Chelin, P., Kutzner, R. D., Brochet, J., Caville, S., Ray, M., Landsheere, X., Cuesta, J., Siour, G., Roustan, Y., Hase, F., and Camy-Peyret, C.: Impact of new retrieval settings on time-series and diurnal variation of retrieved ammonia total columns by ground-based remote sensing (OASIS observatory) over Greater Paris, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-18503, https://doi.org/10.5194/egusphere-egu24-18503, 2024.

08:58–09:00
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PICO5.15
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EGU24-5436
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ECS
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On-site presentation
Alvaro Patricio Prieto Perez, Peter Huszar, and Jan Karlicky

Air quality depends on emissions, but climate and meteorology also play a role in it. To understand better the contribution of each of these factors, we have to study the evolution of air pollution by varying these drivers. In this study, we are investigating the role that changes in emissions play in air-quality following the RCP4.5 and RCP8.5 scenarios for the 2026-2035 and 2046-2055 decades. We assume that the changes of climate conditions are negligible in comparison to changes in emissions, thus isolating the contribution of emission changes in future air pollution. To carry out the study, a simulation with present-day (2010-2019 decade) emissions and meteorology was performed, and another four simulations with future emissions are being carried out at the moment. The emission input for 2010-2019 was compiled using the Flexible Universal Processor for Modeling Emissions (http://www.fume-ep.org/), and the two future decades were created by applying scaling factors on the present-day emissions based on the mentioned RCPs. The simulations are being performed both by the Weather Research and Forecast with online chemistry version 4.0.3 (WRF-Chem) model and the Comprehensive Air-quality Model with Extensions (CAMx) version 7.20. The present-day simulation is being validated by studying several pollutants (such as NO2, O3, SO2, CO, PM10 and PM2.5) and meteorological variables and comparing them with observational data.

How to cite: Prieto Perez, A. P., Huszar, P., and Karlicky, J.: Understanding the role of emissions in future air-quality scenarios over Central Europe, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5436, https://doi.org/10.5194/egusphere-egu24-5436, 2024.

09:00–10:15
Chairperson: Andrea Pozzer
10:45–10:47
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PICO5.1
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EGU24-7806
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ECS
|
On-site presentation
Biomass burning plumes from Indochina towards southern China: the predominant synoptic weather processes
(withdrawn)
Lian Xue, Ke Ding, Xin Huang, Anbao Zhu, Sijia Lou, Zilin Wang, and Aijun Ding
10:47–10:49
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PICO5.2
|
EGU24-9756
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On-site presentation
Bianca Mihalache, Sabina Stefan, and Gabriela Iorga

High levels of atmospheric pollution degrade air quality, affect the climate and have significant impacts on human health. The climate maps show that the region of South-Eastern Romania (SERO) has started to be to be affected by significant climate changes. Therefore, the spatial variations of the trace gases (NO2, CO, SO2, and O3) by investigating their levels and variations in the atmosphere both from ground based measurements, but also from remote sensing in different areas of this region need to be investigated. The selected sites (urban, suburban and rural types) are subject to different sources of pollution and represent well the pollution spread over a larger area within SERO region. A database (2019-2021) was created for each site considering the ground-based data retrieved from Romanian National Air Quality Network, the remote-sensing data retrieved from the Sentinel 5P TROPOMI instrument and also, for one of the sites studied, we used the data available from Pandonia Global Network Pandora instrument. The meteorological parameters were extracted from the European Centre for Medium-Range Weather Forecasts (ECMWF) Era5 single level products and pressure level products.

During the observation period, univariate and bivariate LISA cluster maps indicate the spatial and temporal behavior is linked to local and regional pollution sources, social behavior and the level of economic development. Trans-regional pollution between different areas within SERO region was found to be very strong. Moreover, the statistical analysis of studied trace gasses (NO2, CO, SO2, and O3) in the areas with lowest concentrations and highest concentrations confirmed the need to take in consideration more factors than just pollution sources (such as traffic, industry type, agricultural and biomass burning activities etc.). Results show that the complexity of atmospheric pollution is related to more than just the identification of pollution sources. It implies the necessity to take into account additional metadata. They also highlights important information on the distribution and variation of selected trace gases, with the potential to help the policy makers in addressing measures to reduce these pollutants.

Acknowledgment: BM work was supported by the University of Bucharest, PhD research grant. The partial support from NO Grants 2014-2021, under Project EEA-RO-NO-2019-0423, contract no 31/01.09.2020 is also acknowledged. We thank R.V. Chiritescu for providing LISA maps.

How to cite: Mihalache, B., Stefan, S., and Iorga, G.: Trans-regional pollution between different areas within South – Eastern Romania is very strong, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-9756, https://doi.org/10.5194/egusphere-egu24-9756, 2024.

10:49–10:51
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PICO5.3
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EGU24-16374
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On-site presentation
Joanna Struzewska and Lorenzo Labrador

The Task Force on Measurements and Modelling (TFMM), established in 1999, operates within the framework of the Cooperative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (EMEP). TFMM serves as a platform for the Parties of the United Nations Economic Commission for Europe’s (UNECE) Convention on Long-range Transboundary Air Pollution to exchange knowledge, share experiences, and develop recommendations on air quality issues.   

TFMM offers a valuable opportunity for the Parties and EMEP Centres to engage in discussions regarding the performance of measurements and models. The focus is on getting improvements in methodologies, considering their diverse applications such as national assessments of air quality, evaluation of transboundary fluxes and their impact on air quality, trend analyses, and more.   

Previous initiatives have encompassed comprehensive measurement campaigns and collaborative modelling exercises, contributing to the understanding of atmospheric processes across national borders.   

In the upcoming 2024-2025 work plan a key focus will be a targeted measurement campaign.  Additionally, TFMM aims to conduct a comprehensive modelling exercise specifically geared towards the studying the impact of volatile organic compounds (VOCs) on ozone formation under heatwave conditions. In parallel, the work involves the exploration of the representation of aerosol chemical composition in air quality models.    

Being a hub for collaborative efforts and scientific advancements within the EMEP framework, TFMM extends an open invitation to the scientific community and academia to actively join the TFMM experts’ community.  

How to cite: Struzewska, J. and Labrador, L.: TFMM: Advancing Air Quality Insights and Collaboration within the EMEP Framework  , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-16374, https://doi.org/10.5194/egusphere-egu24-16374, 2024.

10:51–10:53
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PICO5.4
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EGU24-17788
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On-site presentation
Athanasios Nenes, Andrea Baccarini, and Ali Waseem

Anthropogenic activity has caused a dramatic decrease in biodiversity with an estimated 100-1000 fold larger extinction rate compared to the natural background. This biodiversity loss has profound effects on the functioning and stability of ecosystems and consequent adverse societal and economic impacts. Increased deposition of reactive nitrogen (Nr) is one of the major drivers of biodiversity loss, alongside land-use change, biotic exchange, and climate change. The large increase in the input of anthropogenic Nr to the environment is mainly due to combustion, industrial and agricultural processes. The Nr excess is also responsible for degraded soil quality and groundwater pollution.

Emissions of nitrogen oxides (NOx) and ammonia (NH3) are the primary sources of atmospheric Nr, while nitric acid (HNO3) and NH3 drive most of Nr deposition (more than 90% globally). The cycling of N species in the atmosphere is modulated by aerosol acidity, as it drives the partitioning of each species between the gas and particle phase. In particular, the fraction of HNO3 partitioning to the condensed phase decreases with acidity, whereas NH3 has the opposite behavior. Changes in environmental conditions, namely temperature (T) and relative humidity (RH), directly affect aerosol acidity (e.g., a higher RH increases the aerosol water content and decreases the overall acidity – while T has a strong effect in the partitioning constant). Given the large difference in deposition velocity between gas and particles, it is essential to constrain atmospheric acidity to characterize the atmospheric deposition of Nr accurately.

In our study, we used data from the Swiss National Air Pollution Monitoring Network and the ISORROPIA-Lite model to examine aerosol acidity trends over several years, focusing on two Swiss sites: Payerne (agricultural) and Rigi (prealpine). In Payerne, winter brings increased nitrate but reduced acidity due to higher liquid water content. At Rigi, ammonia and sulfate concentrations peak in late spring and summer, about three times higher than in winter, influenced by nearby farming and atmospheric conditions. Despite these variations, aerosol pH at Rigi remains consistently around 3 to 3.5, balanced by the parallel seasonality of ammonia and sulfate. Over the past 14 years, sulfate levels have halved at both sites, as a result of successful emission reduction policies. However, aerosol acidity has remained largely unaffected due to the buffering capacity of ammonia.

Furthermore, we assessed aerosol sensitivity to changes in ammonia and nitrate, along with their deposition patterns. We find that aerosols remain sensitive to both ammonia and nitrate levels throughout the year, although their deposition regimes vary. For instance, in Payerne, nitrate deposition is rapid in summer but slows down in winter. At Rigi, similar patterns are observed for nitrate, with deposition slowing down on about 50% of winter days. Ammonia deposition is consistently fast at both sites, but it slows down for 10-20% of winter days in Rigi.

We conclude by exploring the consequences of these trends for nitrogen emission control strategies and the impact of energy transitions and future climate scenarios on Switzerland's nitrogen cycle, air quality and policy effectiveness.

How to cite: Nenes, A., Baccarini, A., and Waseem, A.: The effect of atmospheric acidity on the reactive nitrogen cycle in Switzerland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-17788, https://doi.org/10.5194/egusphere-egu24-17788, 2024.

10:53–10:55
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PICO5.5
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EGU24-6831
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ECS
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On-site presentation
Adriana Iorga, Jeremy Harrison, and David Moore

Ammonia (NH3) is one of the most important nitrogen gas species and pollutants in the lower troposphere because of the wide usage of nitrogen-based fertilisers in agriculture. Most of the ammonia present in the atmosphere originates from anthropogenic sources, agriculture being the dominant one [1]. Ammonia enters the atmosphere through volatilisation from agricultural soils where fertilisers and/or manure have been spread [2]. Ammonia is a highly unstable gas, reacting chemically with acids to form fine particulate matter (PM2.5), therefore playing an important role in secondary aerosol formation [3]. Wet and dry deposition of ammonia on soils and water bodies is detrimental to ecosystem biodiversity as it leads to acidification of the environment [4]. Therefore, observations of ammonia are essential for establishing air quality and environmental regulations for agricultural practices.

The remote sensing of ammonia presents numerous challenges because ammonia concentrations rapidly change over time and space due to the short life-time of the gas, which ranges from a few hours up to a day [5]. Studying the ammonia diurnal cycle provides valuable information on its sources, surface exchange, deposition and transport processes, and the impact on these by weather and surface conditions; all these are crucial for improving atmospheric models.

The ammonia daily cycle over the Indo-Gangetic Plain in India has been studied using combined satellite observations from the Infrared Atmospheric Sounding Interferometer (IASI) and the Cross-track Infrared Sounder (CrIS) instruments during different months in 2022. By studying the evolution of the ammonia total column concentrations at different satellite overpass times over several days, changes in the ammonia daily cycle can be observed between different seasons. The study makes use of optimal estimation-based retrieval methods developed at the University of Leicester.

 

References:

[1] Clarisse L. et al (2009), Nature Geoscience, 479-483

[2] Van Damme M. et al (2021), Environ. Res. Lett., 16 055017

[3] Erisman, J. W. et al (2007), Environ. Pollut., 150, 140– 149

[4] Krupa S. V. et al (2003), Environ. Pollut., 124, 179-221 

[5] Dammers E. et al (2019), Atmos. Chem. Phys., 12261–12293

How to cite: Iorga, A., Harrison, J., and Moore, D.: Observing the Ammonia Daily Cycle over Agricultural Areas in Asia Using Combined Satellite Measurements, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-6831, https://doi.org/10.5194/egusphere-egu24-6831, 2024.

10:55–10:57
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PICO5.6
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EGU24-3668
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Highlight
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On-site presentation
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Hsin-Cheng Hsieh, Chieh-Heng Wang, Chih-Chung Chang, and Jia-Lin Wang

Toxic volatile organic compounds (VOCs) are part of the hazardous air pollutants (HAPs) or air toxics that affect public health. An approach comprising both online and offline measurement techniques was conducted in a community near an industrial complex for method evaluation and risk assessment. During a month-long field test in this environmental justice community, the instrument of thermal desorption (TD) - gas chromatography-mass spectrometry (GCMS) targeting 86 air toxics was intercompared with two other techniques: direct inlet mass spectrometry (proton transfer reaction quadrupole mass spectrometry or PTR-QMS) and flask sampling for evaluating method suitability. TD-GCMS gathering hourly data was deemed the most suitable online device for source investigation and health risk assessment due to its superior accuracy, species coverage, and data continuity.

The sensitive detection of plumes as spikes near real-time by TD-GCMS established a strong link between source and receptor, which has proven to be effective for tracing the origins of the plumes. Compared to online measurements, random flask sampling tends to miss most of the emission plumes. The concentration spikes in the TD-GCMS data were further aimed for backward trajectory analysis to guide offline sampling in suspected source areas to confirm emission origins.

Although both the online PTR-QMS and TD-GCMS were effective in detecting non-chlorinated species, TD-GCMS proved to be more versatile in detecting both chlorinated and non-chlorinated air toxics with irreplaceable accuracy pivotal for robust hazard assessment resulting from the acute effects, chronic effects, and cancer risks induced by long-term exposure to ambient air toxics.

How to cite: Hsieh, H.-C., Wang, C.-H., Chang, C.-C., and Wang, J.-L.: Source investigation and risk assessment of air toxics in an environmental justice community , EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-3668, https://doi.org/10.5194/egusphere-egu24-3668, 2024.

10:57–10:59
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PICO5.7
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EGU24-2568
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On-site presentation
Evgenia Fedorova, Vladimir Lapchenko, Nikolai Elansky, Vadim Rakitin, and Nastya Vasileva

The work presents the results of a study of a near-surface ozone concentration variability in the Crimea at the background environmental monitoring station in the Karadag Nature Reserve (44°55 north latitude, 35°14 east longitude; 180 m above sea level) for 2012-2021 years with a more detailed analysis of the last six years from 2016 to 2021 years. Ozone measurements at the station are carried out using an APOA-370 gas analyzer (HORIBA, Japan) with an error of no more than 15 μg/m3.

A significantly high-level air pollution of а near-surface ozone was revealed in the observation region, despite the absence of nearby sources of industrial emissions. The maximum hourly average concentration of ozone, equal to 195 µg/m3, was observed on 25.08.2018

To interpret the results obtained, determine the nature of ozone pollution, its relationship with carbon monoxide, and the influence of transboundary and downward transport on ozone concentrations, observations data from the AIRS (Atmospheric InfraRed Sounder, Level 3, v.6 resolution 1°x1°, “ascending only”) orbital spectrometer were used.

The relationship of near-surface ozone concentration and meteorological parameters was investigated. Wind directions leading to increased levels of near-surface ozone pollution are established. Intra-annual variations of near-surface ozone concentration are analyzed. Factors causing the local summer minimum of surface ozone level in some years are established.

Using NOAA HYSPLIT trajectory model and ERA5 reanalysis, a spatial analysis of the atmospheric circulation pattern in the region was carried out. The recurrence of episodes of exceeding the ozone concentration 100 µg/m3 during more than 8 hours (WHO recommendation, further in the text - the standard) was estimated. The frequency of exceeding this standard is about 5% of all measurements for the time-period of 2016–2021. Possible causes of these episodes were determined and discussed. The mechanisms of long-range transport and its contribution to the near-surface ozone regime in the area of the station have been established in different seasons.

Thus, trajectory analysis showed that for cases where the standard is exceeded in the spring, the movement of air masses occurs over the surface of Black Sea under cyclonic circulation processes. The analysis showed that polluted air masses were formed mainly over central Ukraine, Turkey, Romania and Bulgaria. In the summer months, atmospheric transport over the land surface from the eastern direction (Ukraine, southern Russia) predominates.

Annual trends of near-surface ozone concentration in the period 2012-2021 years are estimated as statistically insignificant.

Study was supported by Russian Science Foundation, Project No 20-17-00200.

How to cite: Fedorova, E., Lapchenko, V., Elansky, N., Rakitin, V., and Vasileva, N.: Near-surface ozone variability in the Karadag nature reserve, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2568, https://doi.org/10.5194/egusphere-egu24-2568, 2024.

10:59–11:01
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PICO5.8
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EGU24-1298
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On-site presentation
Real-time measurement of total and water-soluble organic carbon with developed online monitors 
(withdrawn after no-show)
Constantinos Sioutas, Yashar Aghaei, Mohammad Aldekheel, Ramin Tohidi, and Mehdi Badami
11:01–11:03
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PICO5.9
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EGU24-2199
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On-site presentation
Xuguang Chi, Lei Wang, and Caijun Zhu

  Burning firework is a traditional custom in China during Chinese Spring festival period, and the smoke plums releasing from firework burning are responsible for high concentrations of particles (especially trace metals) and gases. In this work,results from in-situ measurements of chemical components of PM2.5 aerosols and trace gases during three successive spring festival campaigns (2016-2018) are reported. The campaigns were carried out at a regional background station, SORPES, located in the western part of the Yangtze River Delta in eastern China. 

Table 1. Median value of selected trace metals, PM2.5 mass, organic carbon, elemental carbon, ions and trace gas concentration during firework events (FW) and background (BG) periods in three campaigns.

   2016 2017 2018
  FW BG FW BG FW BG
ug/m3            
PM2.5 63 54 40 63 59 43
OC 12 7.7 6.5 7.8 4.7 4.4
EC 3.4 2.7 1.8 2.8 2.4 2.7
K 3.1 0.8 1.0 0.5 1.2 0.2
Cl 1.2 1.6 1.0 1.0
1.5
0.8
SO4 11 12 9.2 12 12 7.3
ng/m3            
Sr 60 8.2 16 5.5 35 7.4
Ba 137 14 33 11 87 17
Cu 26 10 9.4 6.1 50 37
As 36 23 11 15 13 11
Pb 139 83 60 75 60 46
Zn 90 109 70 127 73 84
Fe 338 369 150 265 174 318
V 2.3 0.8 1.9 2.2 0.7 0.6
CO(ppm) 0.83 0.53 0.48 0.64 0.56 0.55
SO2(ppb)     2.0 3.6 1.4 2.5

Sr/PM(‰)

1.03 0.2 1.01 0.11 0.98 0.2

 

Median concentrations of selected PM2.5 chemical species and trace metals are summarized in Table1. Clear elevations of Sr, Ba, Cu, K and Cl were observed during firework event period than background period, while no clear elevation were found for other species. Time series illustrated in Fig.1 suggested that in our case, Sr followed by Ba were recognised as the best fireworks tracers because their concentration were very high during firework episode and comparable with the detection limits of instrument during the background period. Similar founding was also observed in Spain (Moreno et al., 2010). The higher Sr/PM2.5 ratio (Table 1) suggest higher contribution of firework emission pollution to PM2.5 during firework events compare to background period (5 to 10 times).

Figure 1. Time series of Sr and Ba during three campaigns in 2016-2018.

  Extremely high enrichment factor was determined for Sr, Ba, Cu, Zn and Pb, suggests that they have anthropogenic origin. Mass concentrations of the trace elements and OC, EC data were input into EPA PMF5.0 model to elucidate the possible dominant source. The results suggest that the dominant sources in three campaigns were firework, coal burning, industry, and traffic. Further analysis on PMF and back trajectory statistics are still need to be done.        

 

 

How to cite: Chi, X., Wang, L., and Zhu, C.: Effect of fireworks events on urban background PM2.5 composition:  measurement of trace elements at SORPES during spring festival periods 2016-2018, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2199, https://doi.org/10.5194/egusphere-egu24-2199, 2024.

11:03–11:05
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EGU24-2653
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ECS
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Virtual presentation
Lu Lei, Kirsten Fossum, Chunshui Lin, Darius Ceburnis, Aqeel Afzal, Teresa Spohn, Emmanuel Chevassus, Colin O'Dowd, and Jurgita Ovadnevaite

The air quality in Ireland was once significantly deteriorated by air pollutants emitted from domestic coal combustion activities in the 1980s. Thanks to the smoky coal ban which was put into force in 1990, the air pollution in Ireland has been improved gradually and surely. However, extreme air pollutions with the mass concentration of submicron aerosols (PM1) exceeding 300 μg m-3 were still observed sporadically during cold months, which were mainly related to domestic solid fuel combustion, and the disproportionate impacts from so-called “low-carbon” and “carbon-neutral” solid fuels (e.g., peat and wood). Moreover, due to the increasing wood stove advertisements and significant fuel price increase caused by Ukrainian-Russian war, the emissions from local solid fuel combustion activities could greatly impair the air quality in Ireland in the future. Since the situation is changing year to year, it’s very critical to conduct continuous field aerosol measurements and have a deeper insight into the medium/long-term variations for more targeted and effective regulations in the future. In this study, based on the parallel real-time measurements of submicron aerosol species at three representative sites over Ireland, the multi-year variations of aerosol chemical composition and source emissions have been analyzed.

The air quality in Dublin has been improved gradually since 2016, with the annual average mass concentration of PM1 decreased from 8.0 μg m-3 in 2016 to 4.1 μg m-3  in 2022, and the total number of days when PM1 concentration exceeds the WHO recommendation value (15 μg m-3) has decreased to 11 days in 2022. Specifically, the extreme air pollutions have been reduced significantly, e.g., the maximum hourly PM1 concentration has decreased to 77 μg m-3 in 2022 compared to 317 μg m-3 in 2016.  The high PM1 concentrations in Dublin were more related to local emissions, especially domestic solid fuel burning, characterized by large contributions from primary organic aerosols. While long-range transport also plays an important role with high fractions of inorganics especially Nitrate (NO3). The chemical composition of PM1 in Dublin was similar over the years, i.e., dominated by Organics (Org) and then followed by NO3 or sulfate (SO4). However, it’s worrisome to find that the mass concentration of SO4 has been increasing since 2021 and showed higher contribution to PM1 especially during cold months, indicating that the sharply increasing fuel prices recently may have led to a change in fuel usage, possibly with more coal and solid fuel combustion in households. This could indicate severe air pollution episodes that need further and more effective regulations in the near future to ensure good enough air quality.  

 

How to cite: Lei, L., Fossum, K., Lin, C., Ceburnis, D., Afzal, A., Spohn, T., Chevassus, E., O'Dowd, C., and Ovadnevaite, J.: Multi‐year variations of submicron aerosol composition and sources in Ireland, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-2653, https://doi.org/10.5194/egusphere-egu24-2653, 2024.

11:05–11:07
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PICO5.10
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EGU24-5307
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On-site presentation
Carlos Ordóñez, Soledad Collazo, and Ricardo García-Herrera

Biomass burning has been identified as a major cause of poor regional air quality and the dominant source of particulate matter (PM) in the Amazon basin. In this study, we analyse the impact of the upper-level jet on PM2.5 (PM with an aerodynamic diameter ≤ 2.5 μm) concentrations in tropical South America (SA) from December to February during the period 2003-2022, using the Copernicus Atmosphere Monitoring Service (CAMS) and ERA5 reanalyses. Furthermore, we investigate the response of air pollutants to the joint modulation of the upper-level jet and El Niño-Southern Oscillation (ENSO). First, a climatological analysis shows that PM in the region is largely composed of organic matter and black carbon, with the highest concentrations and temporal variability in Colombia and northeastern Brazil. Regarding the link with the upper-level circulation, we find that PM2.5 concentrations in northeastern Brazil are reduced on days when the subtropical jet (STJ) is absent, due to increased convection and precipitation over the region. This improvement in air quality is independent of the ENSO phase. Conversely, a prominent STJ inhibits convection and contributes to dry conditions that favour increased biomass burning and elevated pollutant concentrations in the lower troposphere. At a 3-day persistence of these STJ conditions, there is a 90% probability of exceeding the World Health Organisation threshold of 15 μg m-3. In addition, the co-occurrence of a prominent STJ with an El Niño phase acts synergistically to increase pollutant concentrations, as both reduce precipitation in northeastern Brazil. In combination with La Niña, this upper-level pattern does not modulate PM2.5 concentrations because the wet conditions favoured by this ENSO phase prevail, reducing biomass burning. This study provides new insights into the modulation of air quality by the upper-level atmospheric circulation in tropical SA. The results have the potential to improve short-term predictability and can serve as a first step towards the development of a warning system.

How to cite: Ordóñez, C., Collazo, S., and García-Herrera, R.: Impact of Upper-Level Atmospheric Circulation and El Niño-Southern Oscillation Phases on Particulate Matter Concentrations in Tropical South America, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-5307, https://doi.org/10.5194/egusphere-egu24-5307, 2024.

11:07–11:09
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PICO5.11
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EGU24-19818
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On-site presentation
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Ranka Godec, Martina Šilović Hujić, Valentina Gluščić, and Gordana Pehnec

Fine particulate matter, such as PM2.5 and PM1, is a harmful air pollutant from natural and human sources. It impacts the climate and causes respiratory issues. It's classified as a Group 1 carcinogen, and it's the most harmful form of air pollution, causing heart and lung disease and premature death. Aerosols' composition and toxicity vary depending on their source and atmospheric chemistry. The carbon fraction of particulate matter, consisting of both elemental and organic carbon, may cause adverse health effects due to its reductive potential and organic species. It also contributes to global warming due to its radiative properties. Carbonaceous material is a substantial part of particulate matter, with primary organic carbon coming from incomplete combustion and degradation of carbon-containing products. Secondary organic carbon forms through the condensation of organic carbon gases from organic material combustion, fuel evaporation, or natural volatile organic compounds emission.

The objective of this study was to identify and compare the concentrations of elemental carbon (EC) and organic carbon (OC) in PM2.5 and PM1 particles during different seasons and years in order to detect any potential trends of individual pollutants in PM at a single site in Zagreb. Continuous monitoring of mass concentrations of PM1 and PM2.5 particles, along with their carbon content, was carried out for a period of five years, starting from January 1st, 2018, and ending on December 31st, 2022, at an urban background site located in the northern part of Zagreb. Daily samples of PM1 and PM2.5 particle fractions were gathered on pre-fired quartz fiber. Their mass concentrations were determined gravimetrically, while carbon content was analyzed for OC, TC, WSOC, and EC. This was done using the thermal-optical transmittance method, following the EUSAAR_2 protocol. The measurements taken over 5 years showed that the concentration of carbon species in PM1 and PM2.5 varied seasonally. The concentration of carbon pollutants was observed to be higher during cold periods, while it was lower during warmer periods of the 5-year campaign. A weak downward trend in PM1, PM2.5, and OC mass concentrations was observed during the studied period, while EC mass concentrations showed a slight increasing trend.

 

ACKNOWLEDGEMENTS: These measurements were conducted within the internal scientific project of the Institute for Medical Research and Occupational Health “Organic content of PM1 particle fraction” (PI: R. Godec). The results of this research were obtained using the facilities and equipment funded within the European Regional Development Fund project KK.01.1.1.02.0007 "Research and Education Centre of Environmental Health and Radiation Protection – Reconstruction and Expansion of the Institute for Medical Research and Occupational Health".

How to cite: Godec, R., Šilović Hujić, M., Gluščić, V., and Pehnec, G.: The 5-year trend of PM1 and PM2.5 mass concentrations and their carbon content at an urban background site in Zagreb, Croatia, EGU General Assembly 2024, Vienna, Austria, 14–19 Apr 2024, EGU24-19818, https://doi.org/10.5194/egusphere-egu24-19818, 2024.

11:09–11:11
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PICO5.12
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EGU24-20147
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ECS
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On-site presentation
Long-term trends and sources of submicron particle number size distributions at four different sites in Denmark
(withdrawn)
Varun Kumar, Andreas Massling, Claus Nordstrøm, and Thomas Ellermann
11:11–11:13
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PICO5.13
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EGU24-22450
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On-site presentation
Estimation of Ca2+ Wet Deposition in the Northern Hemisphere by Use of CNN Deep-Learning Model
(withdrawn)
Wanying Chen, Xingcheng Lu, and Jimmy C.H. Fung
11:13–12:30