Articles | Volume 25, issue 9
https://doi.org/10.5194/acp-25-4943-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-4943-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 May 2025
Research article |
| 12 May 2025
| 12 May 2025
Validation and uncertainty quantification of three state-of-the-art ammonia surface exchange schemes using NH3 flux measurements in a dune ecosystem
Tycho Jongenelen
CORRESPONDING AUTHOR
Institute of Environmental Science (CML), Leiden University, 2333 CC Leiden, the Netherlands
Margreet van Zanten
National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, the Netherlands
Meteorology and Air Quality Group, Wageningen University and Research, P.O. Box 47, 6700 AA Wageningen, the Netherlands
Enrico Dammers
Institute of Environmental Science (CML), Leiden University, 2333 CC Leiden, the Netherlands
Netherlands Organisation for Applied Scientific Research (TNO), Department Air Quality and Emissions Research, 3584 CB Utrecht, the Netherlands
Roy Wichink Kruit
National Institute for Public Health and the Environment (RIVM), 3720 BA Bilthoven, the Netherlands
Arjan Hensen
Netherlands Organisation for Applied Scientific Research (TNO), P.O. Box 15, 1755 ZG Petten, the Netherlands
Leon Geers
Netherlands Organisation for Applied Scientific Research (TNO), Department Air Quality and Emissions Research, 3584 CB Utrecht, the Netherlands
Jan Willem Erisman
Institute of Environmental Science (CML), Leiden University, 2333 CC Leiden, the Netherlands
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Lidewij Beatrijs Tijhuis, Tyler Wizenberg, and Enrico Dammers
EGUsphere, https://doi.org/10.5194/egusphere-2026-2893, https://doi.org/10.5194/egusphere-2026-2893, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Ammonia is an air pollutant that affects human health, ecosystems, and climate, but satellite measurements usually cannot identify emissions from individual facilities. We show that high‑resolution thermal infrared images can detect ammonia plumes at a much finer scale than existing satellites. This enables clearer identification of industrial sources and provides new opportunities for improved emission estimates and the design of future satellite missions.
Beatriz Herrera, Enrico Dammers, Martine De Maziere, Omaira Garcia, Michel Grutter, James W. Hannigan, Dylan B. A. Jones, Nicholas Jones, Emmanuel Mahieu, Maria Makarova, Kazuyuki Miyazaki, Isamu Morino, Isao Murata, Ivan Ortega, Mathias Palm, Anatoly Poverovskii, Takashi Sekiya, Dan Smale, Hannah Sill, Wolfgang Stremme, Ralf Sussmann, Geoffrey Toon, Corinne Vigouroux, Wei Wang, Tyler Wizenberg, and Kimberly Strong
EGUsphere, https://doi.org/10.5194/egusphere-2026-3138, https://doi.org/10.5194/egusphere-2026-3138, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This work investigates how atmospheric ammonia changes over time using long-term observations and simulations at locations around the world. While its main sources are related to agriculture, wildfires, vehicles, and volcanoes also contribute. The results show that ammonia levels vary strongly during the day and across seasons, and are rising at most locations. These findings improve our understanding of air pollution and its impacts.
Hannes Witt, Ronald J. van der A, Jieying Ding, Jeroen Kuenen, and Margreet C. van Zanten
Atmos. Chem. Phys., 26, 5237–5248, https://doi.org/10.5194/acp-26-5237-2026, https://doi.org/10.5194/acp-26-5237-2026, 2026
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We present a detailed comparison of NOx emissions from the Dutch national emission inventory with completely independent emission data derived from satellite observations with the DECSO algorithm. We find good agreement in overall emission levels, regional emissions, and the 5-year emission trend. Our results demonstrate the robustness of the national inventory and the satellite-derived emissions and might serve as a use-case for the adoption of similar methods in other countries.
Felipe Cifuentes, Henk Eskes, Ankie Piters, Julian Gomez, John Douros, Gaia Pinardi, Martina M. Friedrich, Enrico Dammers, Manuel Gebetsberger, and K. Folkert Boersma
Atmos. Meas. Tech., 19, 2437–2477, https://doi.org/10.5194/amt-19-2437-2026, https://doi.org/10.5194/amt-19-2437-2026, 2026
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Satellite NO2 data are essential for monitoring air pollution, but they are affected by several sources of uncertainty. This study evaluates the major error contributors in TROPOMI (TROPOspheric Monitoring Instrument) NO2 retrievals by analyzing each retrieval step and comparing with ground-based observations. Key findings include biases in the separation of stratospheric and tropospheric NO2, representation and smoothing errors, and substantial variability among the ground-based instruments used for validation.
Tyler Wizenberg, Enrico Dammers, Arjo Segers, Mark W. Shephard, Pierre Coheur, Lieven Clarisse, Martin Van Damme, Henk Eskes, Roy Wichink Kruit, Shelley van der Graaf, and Martijn Schaap
EGUsphere, https://doi.org/10.5194/egusphere-2025-5926, https://doi.org/10.5194/egusphere-2025-5926, 2026
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We combined satellite data on ammonia and nitrogen dioxide concentrations with a regional model to better estimate nitrogen emissions and deposition in the Netherlands. This improved the accuracy of pollution maps and trends, especially in agricultural regions. Our approach helps identify when and where emissions are highest, supporting better air quality management and environmental protection by showing the benefits of using multiple satellite datasets together.
Simeng Li, Enrico Dammers, Arjo Segers, and Jan Willem Erisman
Atmos. Chem. Phys., 25, 15593–15611, https://doi.org/10.5194/acp-25-15593-2025, https://doi.org/10.5194/acp-25-15593-2025, 2025
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Between 2019 and 2022, a notable reduction in livestock numbers has been observed on Schiermonnikoog, a small island in the north of the Netherlands. We have assessed ammonia emissions using real-world measurements on the island, demonstrated emission decrease, and proposed a network to improve emission monitoring.
Zihao Yuan, Guangliang Fu, Hai Xiang Lin, Jan Willem Erisman, and Otto P. Hasekamp
Atmos. Meas. Tech., 18, 5415–5434, https://doi.org/10.5194/amt-18-5415-2025, https://doi.org/10.5194/amt-18-5415-2025, 2025
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This work develops an Neural-Network-based above cloud aerosol (ACA) detection and retrieval scheme for multi-angular polarimetric (MAP) instruments. On one year of the retrieval, the retrieved aerosol properties (aerosol optical thickness, AOT, Angstrom Exponent, AE, and Single Scattering Albedo, SSA) agree well with adjacent clear-sky aerosol retrievals. The seasonal global pattern of ACA events and above cloud AOT are also within expectation.
Leon Geers, Ruud Janssen, Gudrun Thorkelsdottir, Jordi Vilà-Guerau de Arellano, and Martijn Schaap
Geosci. Model Dev., 18, 6647–6669, https://doi.org/10.5194/gmd-18-6647-2025, https://doi.org/10.5194/gmd-18-6647-2025, 2025
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High-resolution data on reactive nitrogen deposition are needed to inform cost-effective policies. Here, we describe the implementation of a dry deposition module in a large eddy simulation code. With this model, we are able to represent the turbulent exchange of tracers at the hectometer resolution. The model calculates the dispersion and deposition of NOx and NH3 in great spatial detail, clearly showing the influence of local land use patterns.
Judith Tettenborn, Daniel Zavala-Araiza, Daan Stroeken, Hossein Maazallahi, Carina van der Veen, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Felix Vogel, Lawson Gillespie, Sebastien Ars, James France, David Lowry, Rebecca Fisher, and Thomas Röckmann
Atmos. Meas. Tech., 18, 3569–3584, https://doi.org/10.5194/amt-18-3569-2025, https://doi.org/10.5194/amt-18-3569-2025, 2025
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Measurements of methane with vehicle-based sensors are an effective method to identify and quantify leaks from urban gas distribution systems. We deliberately released methane in different environments and calibrated the response of different methane analysers when they transected the plumes in a vehicle. We derived an improved statistical function for consistent emission estimations using different instruments. Repeated transects reduce the uncertainty in emission rate estimates.
Chris A. McLinden, Debora Griffin, Vitali Fioletov, Junhua Zhang, Enrico Dammers, Cristen Adams, Mallory Loria, Nickolay Krotkov, and Lok N. Lamsal
Atmos. Chem. Phys., 25, 6093–6120, https://doi.org/10.5194/acp-25-6093-2025, https://doi.org/10.5194/acp-25-6093-2025, 2025
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The Ozone Monitoring Instrument (OMI) was used to understand the evolution of NOx emissions from the Canadian oil sands. OMI NO2 combined with winds and reported stack emissions found emissions from the heavy-hauler mine fleet have remained flat since 2005, whereas the total oil sands mined have more than doubled. This difference is a result of emissions standards that limit NOx emissions becoming more stringent over this period, confirming the efficacy of the policy enacting these standards.
Felipe Cifuentes, Henk Eskes, Enrico Dammers, Charlotte Bryan, and Folkert Boersma
Geosci. Model Dev., 18, 621–649, https://doi.org/10.5194/gmd-18-621-2025, https://doi.org/10.5194/gmd-18-621-2025, 2025
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We tested the capability of the flux divergence approach (FDA) to reproduce known NOx emissions using synthetic NO2 satellite column retrievals from high-resolution model simulations. The FDA accurately reproduced NOx emissions when column observations were limited to the boundary layer and when the variability of the NO2 lifetime, the NOx : NO2 ratio, and NO2 profile shapes were correctly modeled. This introduces strong model dependency, reducing the simplicity of the original FDA formulation.
Jieying Ding, Ronald van der A, Henk Eskes, Enrico Dammers, Mark Shephard, Roy Wichink Kruit, Marc Guevara, and Leonor Tarrason
Atmos. Chem. Phys., 24, 10583–10599, https://doi.org/10.5194/acp-24-10583-2024, https://doi.org/10.5194/acp-24-10583-2024, 2024
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Here we applied the existing Daily Emissions Constrained by Satellite Observations (DECSO) inversion algorithm to NH3 observations from the CrIS satellite instrument to estimate NH3 emissions. As NH3 in the atmosphere is influenced by NOx, we implemented DECSO to estimate NOx and NH3 emissions simultaneously. The emissions are derived over Europe for 2020 at a spatial resolution of 0.2° using daily observations from CrIS and TROPOMI. Results are compared to bottom-up emission inventories.
Debora Griffin, Jack Chen, Kerry Anderson, Paul Makar, Chris A. McLinden, Enrico Dammers, and Andre Fogal
Atmos. Chem. Phys., 24, 10159–10186, https://doi.org/10.5194/acp-24-10159-2024, https://doi.org/10.5194/acp-24-10159-2024, 2024
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Satellite-derived CO emissions provide new insights into the understanding of global CO emission rates from wildfires. We use TROPOMI satellite data to create a global inventory database of wildfire CO emissions. These satellite-derived wildfire emissions are used for the evaluation and improvement of existing fire emission inventories and to examine how the wildfire CO emissions have changed over the past 2 decades.
Xinya Liu, Diego Alves Gouveia, Bas Henzing, Arnoud Apituley, Arjan Hensen, Danielle van Dinther, Rujin Huang, and Ulrike Dusek
Atmos. Chem. Phys., 24, 9597–9614, https://doi.org/10.5194/acp-24-9597-2024, https://doi.org/10.5194/acp-24-9597-2024, 2024
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The vertical distribution of aerosol optical properties is important for their effect on climate. This is usually measured by lidar, which has limitations, most notably the assumption of a lidar ratio. Our study shows that routine surface-level aerosol measurements are able to predict this lidar ratio reasonably well within the lower layers of the atmosphere and thus provide a relatively simple and cost-effective method to improve lidar measurements.
Enrico Dammers, Janot Tokaya, Christian Mielke, Kevin Hausmann, Debora Griffin, Chris McLinden, Henk Eskes, and Renske Timmermans
Geosci. Model Dev., 17, 4983–5007, https://doi.org/10.5194/gmd-17-4983-2024, https://doi.org/10.5194/gmd-17-4983-2024, 2024
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Nitrogen dioxide (NOx) is produced by sources such as industry and traffic and is directly linked to negative impacts on health and the environment. The current construction of emission inventories to keep track of NOx emissions is slow and time-consuming. Satellite measurements provide a way to quickly and independently estimate emissions. In this study, we apply a consistent methodology to derive NOx emissions over Germany and illustrate the value of having such a method for fast projections.
Zihao Yuan, Guangliang Fu, Bastiaan van Diedenhoven, Hai Xiang Lin, Jan Willem Erisman, and Otto P. Hasekamp
Atmos. Meas. Tech., 17, 2595–2610, https://doi.org/10.5194/amt-17-2595-2024, https://doi.org/10.5194/amt-17-2595-2024, 2024
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Currently, aerosol properties from spaceborne multi-angle polarimeter (MAP) instruments can only be retrieved in cloud-free areas or in areas where an aerosol layer is located above a cloud. Therefore, it is important to be able to identify cloud-free pixels for which an aerosol retrieval algorithm can provide meaningful output. The developed neural network cloud screening demonstrates that cloud masking for MAP aerosol retrieval can be based on the MAP measurements themselves.
Xinya Liu, Bas Henzing, Arjan Hensen, Jan Mulder, Peng Yao, Danielle van Dinther, Jerry van Bronckhorst, Rujin Huang, and Ulrike Dusek
Atmos. Chem. Phys., 24, 3405–3420, https://doi.org/10.5194/acp-24-3405-2024, https://doi.org/10.5194/acp-24-3405-2024, 2024
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We evaluated the time-of-flight aerosol chemical speciation monitor (TOF-ACSM) following the implementation of the PM2.5 aerodynamic lens and a capture vaporizer (CV). The results showed that it significantly improved the accuracy and precision of ACSM in the field observations. The paper elucidates the measurement outcomes of various instruments and provides an analysis of their biases. This comprehensive evaluation is expected to benefit the ACSM community and other aerosol field measurements.
Ruben B. Schulte, Jordi Vilà-Guerau de Arellano, Susanna Rutledge-Jonker, Shelley van der Graaf, Jun Zhang, and Margreet C. van Zanten
Biogeosciences, 21, 557–574, https://doi.org/10.5194/bg-21-557-2024, https://doi.org/10.5194/bg-21-557-2024, 2024
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We analyzed measurements with the aim of finding relations between the surface atmosphere exchange of NH3 and the CO2 uptake and transpiration by vegetation. We found a high correlation of daytime NH3 emissions with both latent heat flux and photosynthetically active radiation. Very few simultaneous measurements of NH3, CO2 fluxes and meteorological variables exist at sub-diurnal timescales. This study paves the way to finding more robust relations between the NH3 exchange flux and CO2 uptake.
Camille Viatte, Nadir Guendouz, Clarisse Dufaux, Arjan Hensen, Daan Swart, Martin Van Damme, Lieven Clarisse, Pierre Coheur, and Cathy Clerbaux
Atmos. Chem. Phys., 23, 15253–15267, https://doi.org/10.5194/acp-23-15253-2023, https://doi.org/10.5194/acp-23-15253-2023, 2023
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Ammonia (NH3) is an important air pollutant which, as a precursor of fine particulate matter, raises public health concerns. Models have difficulty predicting events of pollution associated with NH3 since ground-based observations of this gas are still relatively sparse and difficult to implement. We present the first relatively long (2.5 years) and continuous record of hourly NH3 concentrations in Paris to determine its temporal variabilities at different scales to unravel emission sources.
Tobias Christoph Valentin Werner Riess, Klaas Folkert Boersma, Ward Van Roy, Jos de Laat, Enrico Dammers, and Jasper van Vliet
Atmos. Meas. Tech., 16, 5287–5304, https://doi.org/10.5194/amt-16-5287-2023, https://doi.org/10.5194/amt-16-5287-2023, 2023
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Satellite retrievals of trace gases require prior knowledge of the vertical distribution of the pollutant, which is usually obtained from models. Using aircraft-measured vertical NO2 profiles over the North Sea in summer 2021, we evaluate the Transport Model 5 profiles used in the TROPOMI NO2 retrieval. We conclude that driven by the low horizontal resolution and the overestimated vertical mixing, resulting NO2 columns are 20 % too low. This has important implications for emission estimates.
Foteini Stavropoulou, Katarina Vinković, Bert Kers, Marcel de Vries, Steven van Heuven, Piotr Korbeń, Martina Schmidt, Julia Wietzel, Pawel Jagoda, Jaroslav M. Necki, Jakub Bartyzel, Hossein Maazallahi, Malika Menoud, Carina van der Veen, Sylvia Walter, Béla Tuzson, Jonas Ravelid, Randulph Paulo Morales, Lukas Emmenegger, Dominik Brunner, Michael Steiner, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Hugo Denier van der Gon, Antonio Delre, Maklawe Essonanawe Edjabou, Charlotte Scheutz, Marius Corbu, Sebastian Iancu, Denisa Moaca, Alin Scarlat, Alexandru Tudor, Ioana Vizireanu, Andreea Calcan, Magdalena Ardelean, Sorin Ghemulet, Alexandru Pana, Aurel Constantinescu, Lucian Cusa, Alexandru Nica, Calin Baciu, Cristian Pop, Andrei Radovici, Alexandru Mereuta, Horatiu Stefanie, Alexandru Dandocsi, Bas Hermans, Stefan Schwietzke, Daniel Zavala-Araiza, Huilin Chen, and Thomas Röckmann
Atmos. Chem. Phys., 23, 10399–10412, https://doi.org/10.5194/acp-23-10399-2023, https://doi.org/10.5194/acp-23-10399-2023, 2023
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In this study, we quantify CH4 emissions from onshore oil production sites in Romania at source and facility level using a combination of ground- and drone-based measurement techniques. We show that the total CH4 emissions in our studied areas are much higher than the emissions reported to UNFCCC, and up to three-quarters of the detected emissions are related to operational venting. Our results suggest that oil and gas production infrastructure in Romania holds a massive mitigation potential.
Daan Swart, Jun Zhang, Shelley van der Graaf, Susanna Rutledge-Jonker, Arjan Hensen, Stijn Berkhout, Pascal Wintjen, René van der Hoff, Marty Haaima, Arnoud Frumau, Pim van den Bulk, Ruben Schulte, Margreet van Zanten, and Thomas van Goethem
Atmos. Meas. Tech., 16, 529–546, https://doi.org/10.5194/amt-16-529-2023, https://doi.org/10.5194/amt-16-529-2023, 2023
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During a 5-week comparison campaign, we tested two set-ups to measure half hourly ammonia fluxes. The eddy covariance and flux gradient systems showed very similar results when the upwind terrain was both homogeneous and free of obstacles. We discuss the technical performance and practical limitations of both systems. Measurements from these instruments can facilitate the study of processes behind ammonia deposition, an important contributor to eutrophication and acidificationin natural areas.
Marsailidh M. Twigg, Augustinus J. C. Berkhout, Nicholas Cowan, Sabine Crunaire, Enrico Dammers, Volker Ebert, Vincent Gaudion, Marty Haaima, Christoph Häni, Lewis John, Matthew R. Jones, Bjorn Kamps, John Kentisbeer, Thomas Kupper, Sarah R. Leeson, Daiana Leuenberger, Nils O. B. Lüttschwager, Ulla Makkonen, Nicholas A. Martin, David Missler, Duncan Mounsor, Albrecht Neftel, Chad Nelson, Eiko Nemitz, Rutger Oudwater, Celine Pascale, Jean-Eudes Petit, Andrea Pogany, Nathalie Redon, Jörg Sintermann, Amy Stephens, Mark A. Sutton, Yuk S. Tang, Rens Zijlmans, Christine F. Braban, and Bernhard Niederhauser
Atmos. Meas. Tech., 15, 6755–6787, https://doi.org/10.5194/amt-15-6755-2022, https://doi.org/10.5194/amt-15-6755-2022, 2022
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Ammonia (NH3) gas in the atmosphere impacts the environment, human health, and, indirectly, climate. Historic NH3 monitoring was labour intensive, and the instruments were complicated. Over the last decade, there has been a rapid technology development, including “plug-and-play” instruments. This study is an extensive field comparison of the currently available technologies and provides evidence that for routine monitoring, standard operating protocols are required for datasets to be comparable.
Beatriz Herrera, Alejandro Bezanilla, Thomas Blumenstock, Enrico Dammers, Frank Hase, Lieven Clarisse, Adolfo Magaldi, Claudia Rivera, Wolfgang Stremme, Kimberly Strong, Camille Viatte, Martin Van Damme, and Michel Grutter
Atmos. Chem. Phys., 22, 14119–14132, https://doi.org/10.5194/acp-22-14119-2022, https://doi.org/10.5194/acp-22-14119-2022, 2022
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This work investigates atmospheric ammonia (NH3), a key trace gas with consequences for the environment and human health, in Mexico City. The results from the ground-based and satellite instruments show the variability and spatial distribution of NH3 over this region. NH3 in Mexico City has been increasing for the past 10 years and most of its sources are urban. This work contributes to a better understanding of NH3 sources and variability in urban and remote areas.
Ruben B. Schulte, Margreet C. van Zanten, Bart J. H. van Stratum, and Jordi Vilà-Guerau de Arellano
Atmos. Chem. Phys., 22, 8241–8257, https://doi.org/10.5194/acp-22-8241-2022, https://doi.org/10.5194/acp-22-8241-2022, 2022
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We present a fine-scale simulation framework, utilizing large-eddy simulations, to assess NH3 measurements influenced by boundary-layer dynamics and turbulent dispersion of a nearby emission source. The minimum required distance from an emission source differs for concentration and flux measurements, from 0.5–3.0 km and 0.75–4.5 km, respectively. The simulation framework presented here proves to be a powerful and versatile tool for future NH3 research at high spatio-temporal resolutions.
Michael Sitwell, Mark W. Shephard, Yves Rochon, Karen Cady-Pereira, and Enrico Dammers
Atmos. Chem. Phys., 22, 6595–6624, https://doi.org/10.5194/acp-22-6595-2022, https://doi.org/10.5194/acp-22-6595-2022, 2022
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Observations of ammonia made using the satellite-borne CrIS instrument were used to improve the ammonia emissions used in the GEM-MACH model. These observations were used to refine estimates of the monthly mean ammonia emissions over North America for May to August 2016. The updated ammonia emissions reduced biases of GEM-MACH surface ammonia fields with surface observations and showed some improvements in the forecasting of species involved in inorganic particulate matter formation.
Anja Ražnjević, Chiel van Heerwaarden, Bart van Stratum, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, and Maarten Krol
Atmos. Chem. Phys., 22, 6489–6505, https://doi.org/10.5194/acp-22-6489-2022, https://doi.org/10.5194/acp-22-6489-2022, 2022
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Mobile measurement techniques (e.g., instruments placed in cars) are often employed to identify and quantify individual sources of greenhouse gases. Due to road restrictions, those observations are often sparse (temporally and spatially). We performed high-resolution simulations of plume dispersion, with realistic weather conditions encountered in the field, to reproduce the measurement process of a methane plume emitted from an oil well and provide additional information about the plume.
Shelley van der Graaf, Enrico Dammers, Arjo Segers, Richard Kranenburg, Martijn Schaap, Mark W. Shephard, and Jan Willem Erisman
Atmos. Chem. Phys., 22, 951–972, https://doi.org/10.5194/acp-22-951-2022, https://doi.org/10.5194/acp-22-951-2022, 2022
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CrIS NH3 satellite observations are assimilated into the LOTOS-EUROS model using two different methods. In the first method the data are used to fit spatially varying NH3 emission time factors. In the second method a local ensemble transform Kalman filter is used. Compared to in situ observations, combining both methods led to the most significant improvements in the modeled concentrations and deposition, illustrating the usefulness of CrIS NH3 to improve the spatiotemporal distribution of NH3.
Debora Griffin, Chris A. McLinden, Enrico Dammers, Cristen Adams, Chelsea E. Stockwell, Carsten Warneke, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Kyle J. Zarzana, Jake P. Rowe, Rainer Volkamer, Christoph Knote, Natalie Kille, Theodore K. Koenig, Christopher F. Lee, Drew Rollins, Pamela S. Rickly, Jack Chen, Lukas Fehr, Adam Bourassa, Doug Degenstein, Katherine Hayden, Cristian Mihele, Sumi N. Wren, John Liggio, Ayodeji Akingunola, and Paul Makar
Atmos. Meas. Tech., 14, 7929–7957, https://doi.org/10.5194/amt-14-7929-2021, https://doi.org/10.5194/amt-14-7929-2021, 2021
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Satellite-derived NOx emissions from biomass burning are estimated with TROPOMI observations. Two common emission estimation methods are applied, and sensitivity tests with model output were performed to determine the accuracy of these methods. The effect of smoke aerosols on TROPOMI NO2 columns is estimated and compared to aircraft observations from four different aircraft campaigns measuring biomass burning plumes in 2018 and 2019 in North America.
Jonathan E. Hickman, Niels Andela, Enrico Dammers, Lieven Clarisse, Pierre-François Coheur, Martin Van Damme, Courtney A. Di Vittorio, Money Ossohou, Corinne Galy-Lacaux, Kostas Tsigaridis, and Susanne E. Bauer
Atmos. Chem. Phys., 21, 16277–16291, https://doi.org/10.5194/acp-21-16277-2021, https://doi.org/10.5194/acp-21-16277-2021, 2021
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Ammonia (NH3) gas emitted from soils and biomass burning contributes to particulate air pollution. We used satellite observations of the atmosphere over Africa to show that declines in NH3 concentrations over South Sudan's Sudd wetland in 2008–2017 are related to variation in wetland extent. We also find NH3 concentrations increased in West Africa as a result of biomass burning and increased in the Lake Victoria region, likely due to agricultural expansion and intensification.
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Short summary
This article compares three ammonia (NH3) deposition models in a dune ecosystem and investigates the uncertainty of these models. The Zhang model aligned best with the measurements, whereas the DEPAC (DEPosition of Acidifying Compounds) and Massad models overestimated and underestimated the NH3 deposition respectively. The study found that NH3 exchange with wet plant leaves was an important but uncertain process. It offers recommendations to improve future models and suggests measurements to lower the existing uncertainty.
This article compares three ammonia (NH3) deposition models in a dune ecosystem and investigates...
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