TY - JOUR TI - A 3°C global RCP8.5 emission trajectory cancels benefits of European emission reductions on air quality AU - A. Fortems-Cheiney, , G. Foret, G. Siour, R. Vautard, S. Szopa, G. Dufour, A. Colette, G. Lacressonniere AU - Beekmann, M. T2 - Nature Communications DA - 2017/// PY - 2017 VL - 8 IS - 89 ER - TY - JOUR TI - Volatile and intermediate volatility organic compounds in suburban Paris: variability, origin and importance for SOA formation AU - Ait-Helal, W. AU - Borbon, A. AU - Sauvage, S. AU - de Gouw, J. A. AU - Colomb, A. AU - Gros, V. AU - Freutel, F. AU - Crippa, M. AU - Afif, C. AU - Baltensperger, U. AU - Beekmann, M. AU - Doussin, J. F. AU - Durand-Jolibois, R. AU - Fronval, I. AU - Grand, N. AU - Leonardis, T. AU - Lopez, M. AU - Michoud, V. AU - Miet, K. AU - Perrier, S. AU - Prévôt, A. S. H. AU - Schneider, J. AU - Siour, G. AU - Zapf, P. AU - Locoge, N. T2 - Atmos. Chem. Phys. DA - 2014/// PY - 2014 VL - 14 IS - 19 SP - 10439 EP - 10464 ER - TY - JOUR TI - Changes in spatial patterns of ammonia dry deposition flux and deposition threshold exceedance according to dispersion model formalism and horizontal resolution AU - Azouz, Niramson AU - Beekmann, Matthias AU - Siour, Guillaume AU - Cellier, Pierre AU - Drouet, Jean-Louis T2 - Environmental Pollution AB - Ammonia (NH3) emitted into the atmosphere from agricultural sources may affect nearby sensitive ecosystems due to high dry deposition fluxes on vegetation and soil surfaces, contributing to critical load exceedances. Ammonia fluxes near sources are simulated by either short-range atmospheric models or regional models using large grid cell sizes. However, studies are missing on the comparison of the results simulated by these two types of models. This paper presents the effect of model formalism, input factors, especially grid cell size and wind speed and the choice of deposition threshold on the spatial patterns of NH3 dry deposition fluxes and deposition threshold exceedances. We used the Eulerian chemistry-transport model CHIMERE and the Gaussian plume model OPS-ST on two study domains characterised by contrasting land use. We showed that the average annual NH3 dry deposition fluxes over each whole domain are similar for both models. By contrast, NH3 dry deposition fluxes near sources are higher when simulated with OPS-ST that provides analytical solutions that can be sampled with small grid cell sizes (i.e., from 25 to 1600 m in this study), than with CHIMERE, which uses large grid cell sizes (i.e., 800 and 1600 m). As a result, the spatial patterns of deposition threshold exceedance were very different between both models. These patterns depend mainly on grid cell size, the input factors and the choice of the deposition threshold value. We show that the model formalism has a relatively small effect on the results and that the differences result mainly from the spatial resolutions to which they can be applied. Simulation results must therefore be interpreted carefully, taking into account the simulation conditions. DA - 2020/// PY - 2020 VL - 268 SP - 115823 KW - Ammonia fluxes OPS-ST model CHIMERE model Sub-grid variability Landscape ER - TY - GEN TI - Comparison of spatial patterns of ammonia concentration and dry deposition flux between a regional Eulerian chemistry-transport model and a local Gaussian plume model AU - Azouz, Niramson AU - Drouet, Jean-Louis AU - Beekmann, Matthias AU - Siour, Guillaume AU - Wichink Kruit, Roy AU - Cellier, Pierre AB - Agricultural activities are the principal sources of ammonia (NH3) emitted into the atmosphere. High ammonia deposition flux may impact sensitive ecosystems. Regional models of NH3 dispersion, transport and deposition may under- or overestimate NH3 fluxes. We compared NH3 dry deposition fluxes simulated with local and regional models on different theoretical scenarios characterised by varying the values of several input factors: grid cell sizes, characteristics of the NH3 sources such as location and emission rate, characteristics such as canopy resistance (Rc) or roughness length (z0) at the NH3 sinks, and meteorological conditions such as wind speed and direction. Our results showed that, for a given grid cell size, both models provide similar predictions of average NH3 concentration and dry deposition flux over the whole simulation domain. A sensitivity analysis of NH3 concentration and dry deposition flux to wind speed and to surface resistance also showed a similar behaviour between both models. However, the differences of model formalism and changes in the values of the input factors, especially grid cell size and vertical resolution, provide different spatial patterns of NH3 dry deposition flux and concentration. Our results would suggest that regional models operating with large grid cell sizes (e.g. larger than 1 km) could not predict accurately patterns of NH3 dry deposition fluxes close to the sources (e.g. a few tens or hundreds of metres) on heterogeneous landscapes in terms of NH3 fluxes. DA - 2019/04/13/ PY - 2019 ER - TY - JOUR TI - Evaluation of receptor and chemical transport models for PM10 source apportionment AU - Belis, C. A. AU - Pernigotti, D. AU - Pirovano, G. AU - Favez, O. AU - Jaffrezo, J. L. AU - Kuenen, J. AU - van Der Gon, H. D. AU - Reizer, M. AU - Riffault, V. AU - Alleman, L. Y. AU - Almeida, M. AU - Amato, F. AU - Angyal, A. AU - Argyropoulos, G. AU - Bande, S. AU - Beslic, I. AU - Besombes, J. L. AU - Bove, M. C. AU - Brotto, P. AU - Calori, G. AU - Cesari, D. AU - Colombi, C. AU - Contini, D. AU - De Gennaro, G. AU - Di Gilio, A. AU - Diapouli, E. AU - El Haddad, I. AU - Elbern, H. AU - Eleftheriadis, K. AU - Ferreira, J. AU - Vivanco, M. G. AU - Gilardoni, S. AU - Golly, B. AU - Hellebust, S. AU - Hopke, P. K. AU - Izadmanesh, Y. AU - Jorquera, H. AU - Krajsek, K. AU - Kranenburg, R. AU - Lazzeri, P. AU - Lenartz, F. AU - Lucarelli, F. AU - Maciejewska, K. AU - Manders, A. AU - Manousakas, M. AU - Masiol, M. AU - Mircea, M. AU - Mooibroek, D. AU - Nava, S. AU - Oliveira, D. AU - Paglione, M. AU - Pandolfi, M. AU - Perrone, M. AU - Petralia, E. AU - Pietrodangelo, A. AU - Pillon, S. AU - Pokorna, P. AU - Prati, P. AU - Salameh, D. AU - Samara, C. AU - Samek, L. AU - Saraga, D. AU - Sauvage, S. AU - Schaap, M. AU - Scotto, F. AU - Sega, K. AU - Siour, G. AU - Tauler, R. AU - Valli, G. AU - Vecchi, R. AU - Venturini, E. AU - Vestenius, M. AU - Waked, A. AU - Yubero, E. T2 - Atmospheric Environment-X DA - 2019/// PY - 2019 VL - 5 ER - TY - GEN TI - The Respective Roles of Wind Speed and Green Vegetation in Controlling Sahelian Dust Emission During the Wet Season AU - Bergametti, G. AU - Marticorena, B. AU - Rajot, J. L. AU - Siour, G. AU - Féron, A. AU - Gaimoz, C. AU - Coman, A. AU - Chatenet, B. AU - Coulibaly, M. AU - Maman, A. AU - Koné, I. AU - Zakou, A. AB - Abstract Based on 10 years of continuous measurements of wind speed, rainfall, and PM10 concentrations (i.e., concentrations of the particulate matter having a diameter lower than 10 μm) performed in two Sahelian stations, we examine how wind speed and vegetation interact during the wet season to control the dust concentration when it is due to local dust emissions. The results clearly show that the frequency of the high wind speeds is higher at the beginning of the wet season and is the main driver of the seasonal dust emission. During the second part of the wet season, the frequency of high wind speeds is much lower and, in addition, their efficiency for wind erosion and dust emission is strongly affected by the vegetation whose growth reduces progressively PM10 concentrations up to 80%. DA - 2020/// PY - 2020 ER - TY - JOUR TI - What Can We Expect from Data Assimilation for Air Quality Forecast? Part II: Analysis with a Semi-Real Case AU - Bessagnet, B. AU - Menut, L. AU - Couvidat, F. AU - Meleux, F. AU - Siour, G. AU - Mailler, S. T2 - Journal of Atmospheric and Oceanic Technology DA - 2019/// PY - 2019 VL - 36 IS - 7 SP - 1433 EP - 1448 ER - TY - JOUR TI - High Resolution Chemistry Transport Modeling with the On-Line CHIMERE-WRF Model over the French Alps—Analysis of a Feedback of Surface Particulate Matter Concentrations on Mountainous Meteorology AU - Bessagnet, B. AU - Menut, L. AU - Lapere, R. AU - Couvidat, F. AU - Jaffrezo, J.-L. AU - Mailler, S. AU - Favez, O. AU - Pennel, R. AU - Siour, G T2 - Atmosphere DA - 2020/// PY - 2020 VL - 11 SP - 565 ER - TY - JOUR TI - Improving direct normal irradiance retrieval in cloud-free, but high aerosol load conditions by using aerosol optical depth AU - Boraiy, M. AU - Korany, M. AU - Aoun, Y. AU - Alfaro, S.C. AU - El-Metwally, M. AU - Abdel Wahab, M.M. AU - Blanc, P. AU - Eissa, Y. AU - Ghedira, H. AU - Siour, G. AU - Hungershoefer, K. AU - Wald, L. T2 - Meteorologische Zeitschrift DA - 2017/// PY - 2017 ER - TY - JOUR TI - Simulation of fine organic aerosols in the western Mediterranean area during the ChArMEx 2013 summer campaign AU - Cholakian, A. AU - Beekmann, M. AU - Colette, A. AU - Coll, I. AU - Siour, G. AU - Sciare, J. AU - Marchand, N. AU - Couvidat, F. AU - Pey, J. AU - Gros, V. AU - Sauvage, S. AU - Michoud, V. AU - Sellegri, K. AU - Colomb, A. AU - Sartelet, K. AU - Langley DeWitt, H. AU - Elser, M. AU - Prévot, A. S. H. AU - Szidat, S. AU - Dulac, F. T2 - Atmos. Chem. Phys. DA - 2018/// PY - 2018 VL - 18 IS - 10 SP - 7287 EP - 7312 ER - TY - JOUR TI - Simulation of organic aerosol, its precursors, and related oxidants in the Landes pine forest in southwestern France: accounting for domain-specific land use and physical conditions AU - Cholakian, A. AU - Beekmann, M. AU - Siour, G. AU - Coll, I. AU - Cirtog, M. AU - Ormeño, E. AU - Flaud, P. M. AU - Perraudin, E. AU - Villenave, E. T2 - Atmos. Chem. Phys. DA - 2023/// PY - 2023 VL - 23 IS - 6 SP - 3679 EP - 3706 ER - TY - JOUR TI - Modélisation de l'export de polluants atmosphériques depuis les grandes zones urbanisées européennes AU - Coll, I. AU - Siour, G. AU - Colette, A. AU - Bessagnet, B. T2 - La Météorologie AB - La dimension et la compacité des grandes villes ont un effet structurant sur le rejet de polluants primaires anthropiques dans l’atmosphère. Une fois émis, les polluants s’oxydent à une vitesse et avec une efficacité qui sont fortement contraintes par la structure des panaches urbains. Dans le cadre de la gestion de la qualité de l’air et des problèmes climatiques, il est donc nécessaire de prendre en compte l’organisation actuelle et future des émissions urbaines afin d’estimer leur impact sur la pollution troposphérique à différentes échelles. Nous présentons ici une analyse par modélisation numérique de la relation entre villes, qualité de l’air et export de polluants, à l’aide du modèle de chimie-transport CHIMERE.Nos résultats montrent que, comme attendu, les exports de polluants primaires et secondaires sont très sensibles à la forme, à l’étendue et au positionnement géographique des villes, qui confèrent une très grande variabilité au flux de précurseurs d’ozone le long du trajet des panaches urbains. DA - 2012/// PY - 2012 VL - 79 SP - 25 EP - 33 ER - TY - JOUR TI - Ozone pollution during the COVID-19 lockdown in the spring of 2020 over Europe, analysed from satellite observations, in situ measurements, and models AU - Cuesta, J. AU - Costantino, L. AU - Beekmann, M. AU - Siour, G. AU - Menut, L. AU - Bessagnet, B. AU - Landi, T. C. AU - Dufour, G. AU - Eremenko, M. T2 - Atmos. Chem. Phys. DA - 2022/// PY - 2022 VL - 22 IS - 7 SP - 4471 EP - 4489 ER - TY - GEN TI - Response of surface ozone concentration to emission reduction and meteorology during the COVID-19 lockdown in Europe AU - Deroubaix, Adrien AU - Brasseur, Guy AU - Gaubert, Benjamin AU - Labuhn, Inga AU - Menut, Laurent AU - Siour, Guillaume AU - Tuccella, Paolo AB - Abstract The lockdown period (March–May 2020) during the COVID-19 pandemic in Europe led to a reduction in the anthropogenic emissions of primary pollutants. For three-quarters of over 1,100 available monitoring stations, the average nitrogen dioxide (NO2) concentrations decreased by at least 2.7 μg·m−3 (or 25%) compared with the average concentrations recorded during the same period of the previous seven years. This reduction was not specific to urban or rural areas because the relative reduction was of similar magnitude in both areas. The ozone (O3) response differed spatially, with positive anomalies in Northern Europe and negative anomalies in Southwestern Europe. Reduced cloudiness and related enhanced radiation in Northern Europe played a significant role in the increase of surface O3 concentrations by shifting the photochemical partitioning between NO2 and O3 toward more O3. The level of total oxidant (Ox = O3 + NO2) remained unchanged, except in Southwestern Europe where it decreased. Several episodes lasting a few days of a high level of total oxidants were observed in Northern Europe. The results illustrate the complexity of the atmospheric response to the unprecedented reduction in the emission of primary pollutants. DA - 2021/// PY - 2021 ER - TY - JOUR TI - Interactions of atmospheric gases and aerosols with the monsoon dynamics over the Sudano-Guinean region during AMMA AU - Deroubaix, A. AU - Flamant, C. AU - Menut, L. AU - Siour, G. AU - Mailler, S. AU - Turquety, S. AU - Briant, R. AU - Khvorostyanov, D. AU - Crumeyrolle, S. T2 - Atmos. Chem. Phys. DA - 2018/// PY - 2018 VL - 18 IS - 1 SP - 445 EP - 465 ER - TY - JOUR TI - Large uncertainties in trends of energy demand for heating and cooling under climate change AU - Deroubaix, Adrien AU - Labuhn, Inga AU - Camredon, Marie AU - Gaubert, Benjamin AU - Monerie, Paul-Arthur AU - Popp, Max AU - Ramarohetra, Johanna AU - Ruprich-Robert, Yohan AU - Silvers, Levi G. AU - Siour, Guillaume T2 - Nature Communications AB - The energy demand for heating and cooling buildings is changing with global warming. Using proxies of climate-driven energy demand based on the heating and cooling Degree-Days methodology applied to thirty global climate model simulations, we show that, over all continental areas, the climate-driven energy demand trends for heating and cooling were weak, changing by less than 10% from 1950 to 1990, but become stronger from 1990 to 2030, changing by more than 10%. With the multi-model mean, the increasing trends in cooling energy demand are more pronounced than the decreasing trends in heating. The changes in cooling, however, are highly variable depending on individual simulations, ranging from a few to several hundred percent in most of the densely populated mid-latitude areas. This work presents an example of the challenges that accompany future energy demand quantification as a result of the uncertainty in the projected climate. DA - 2021/// PY - 2021 VL - 12 IS - 1 SP - 5197 ER - TY - JOUR TI - Sensitivity of low-level clouds and precipitation to anthropogenic aerosol emission in southern West Africa: a DACCIWA case study AU - Deroubaix, A. AU - Menut, L. AU - Flamant, C. AU - Knippertz, P. AU - Fink, A. H. AU - Batenburg, A. AU - Brito, J. AU - Denjean, C. AU - Dione, C. AU - Dupuy, R. AU - Hahn, V. AU - Kalthoff, N. AU - Lohou, F. AU - Schwarzenboeck, A. AU - Siour, G. AU - Tuccella, P. AU - Voigt, C. T2 - Atmos. Chem. Phys. DA - 2022/// PY - 2022 VL - 22 IS - 5 SP - 3251 EP - 3273 ER - TY - JOUR TI - Aerosol optical depth climatology from the high-resolution MAIAC product over Europe: differences between major European cities and their surrounding environments AU - Di Antonio, L. AU - Di Biagio, C. AU - Foret, G. AU - Formenti, P. AU - Siour, G. AU - Doussin, J. F. AU - Beekmann, M. T2 - Atmos. Chem. Phys. DA - 2023/// PY - 2023 VL - 23 IS - 19 SP - 12455 EP - 12475 ER - TY - JOUR TI - Recent ozone trends in the Chinese free troposphere: role of the local emission reductions and meteorology AU - Dufour, G. AU - Hauglustaine, D. AU - Zhang, Y. AU - Eremenko, M. AU - Cohen, Y. AU - Gaudel, A. AU - Siour, G. AU - Lachatre, M. AU - Bense, A. AU - Bessagnet, B. AU - Cuesta, J. AU - Ziemke, J. AU - Thouret, V. AU - Zheng, B. T2 - Atmos. Chem. Phys. DA - 2021/// PY - 2021 VL - 21 IS - 20 SP - 16001 EP - 16025 ER - TY - JOUR TI - 24 h Evolution of an Exceptional HONO Plume Emitted by the Record-Breaking 2019/2020 Australian Wildfire Tracked from Space AU - Dufour, M.;, G.; Eremenko AU - Siour, J.;, G.; Sellitto, P.; Cuesta AU - Perrin, M, A.; Beekmann T2 - Atmosphere AB - Megafires occurred in Australia during the 2019/2020 bushfire season, leading to enhanced concentrations of many tropospheric pollutants. Here, we report on a fire plume with unusually high and persistent nitrous acid (HONO) levels that we could track during one day at free tropospheric levels over the Tasman Sea on 4 January 2020 using IASI and CrIS satellite observations. HONO concentrations up to about 25 ppb were retrieved during nighttime. Persistent HONO concentrations (>10 ppb) were still observed at sunrise, likely due to large aerosol concentrations within the plume, preventing HONO photodissociation. In addition, comparison with carbon monoxide (CO) measurements suggest a secondary production during the plume transport. Model simulations confirm that the plume is transported in the lower free troposphere with concentrations as high as 30 ppb at about 4 km. However, many uncertainties and unknowns remain in the plume aerosol load and in the chemical processes which may explain the model inability to reproduce elevated HONO concentrations at sunrise. DA - 2022/// PY - 2022 VL - 13 IS - 9 KW - nitrous acid biomass burning remote sensing ER - TY - JOUR TI - Prediction and forecast of surface wind using ML tree-based algorithms AU - ElTaweel, M. H. AU - Alfaro, S. C. AU - Siour, G. AU - Coman, A. AU - Robaa, S. M. AU - Wahab, M. M. Abdel T2 - Meteorology and Atmospheric Physics AB - This study focuses on the importance of reliable surface wind forecasts for various sectors, particularly energy production. Traditional numerical weather prediction models are facing limitations and increasing complexity, leading to the development of machine learning models as alternatives or supplements. The research consists of two stages. In the first stage, the ERA5 database is used to evaluate the long-term performance of different combinations of features and two tree-based algorithms for predicting surface wind characteristics (speed and direction) in Cairo. The XGBoost algorithm slightly outperforms the Random Forest algorithm, especially when combined with appropriate feature selection. Even three years after the training period, the results remain very good, with an RMSE of 0.59 m/s, rRMSE of 17%, and R2 of 0.84. The second stage assesses the multivariate approach's ability to forecast wind speed evolution at different time horizons (1–12 h) during a week characterized by significant wind dynamics. The forecasts demonstrate excellent agreement with observations at a 1-h time horizon, with an RMSE of 0.35 m/s, rRMSE of 7.6%, and R2 of 0.98, surpassing or comparable to other literature results. However, as the time lag increases, the RMSE (0.86, 1.14, and 1.51 m/s for 3, 6, and 12 h, respectively) and rRMSE (18.7%, 24.8%, and 32.9% for 3, 6, and 12 h, respectively) also increase, while R2 decreases (0.86, 0.79, and 0.60). Furthermore, the wind variations' amplitude is underestimated. To address this bias, a simple correction method is proposed. DA - 2023/// PY - 2023 VL - 136 IS - 1 SP - 1 ER - TY - JOUR TI - The December 2016 extreme weather and particulate matter pollution episode in the Paris region (France) AU - Foret, G. AU - Michoud, V. AU - Kotthaus, S. AU - Petit, J. E. AU - Baudic, A. AU - Siour, G. AU - Kim, Y. AU - Doussin, J. F. AU - Dupont, J. C. AU - Formenti, P. AU - Gaimoz, C. AU - Ghersi, V. AU - Gratien, A. AU - Gros, V. AU - Jaffrezo, J. L. AU - Haeffelin, M. AU - Kreitz, M. AU - Ravetta, F. AU - Sartelet, K. AU - Simon, L. AU - Té, Y. AU - Uzu, G. AU - Zhang, S. AU - Favez, O. AU - Beekmann, M. T2 - Atmospheric Environment DA - 2022/// PY - 2022 SP - 119386 ER - TY - JOUR TI - Three years of measurements of light-absorbing aerosols over coastal Namibia: seasonality, origin, and transport AU - Formenti, P. AU - Piketh, S. J. AU - Namwoonde, A. AU - Klopper, D. AU - Burger, R. AU - Cazaunau, M. AU - Feron, A. AU - Gaimoz, C. AU - Broccardo, S. AU - Walton, N. AU - Desboeufs, K. AU - Siour, G. AU - Hanghome, M. AU - Mafwila, S. AU - Omoregie, E. AU - Junkermann, W. AU - Maenhaut, W. T2 - Atmos. Chem. Phys. DA - 2018/// PY - 2018 VL - 18 IS - 23 SP - 17003 EP - 17016 ER - TY - GEN TI - Analysis of the Anthropogenic and Biogenic NOx Emissions Over 2008–2017: Assessment of the Trends in the 30 Most Populated Urban Areas in Europe AU - Fortems-Cheiney, A. AU - Broquet, G. AU - Pison, I. AU - Saunois, M. AU - Potier, E. AU - Berchet, A. AU - Dufour, G. AU - Siour, G. AU - Denier van der Gon, H. AU - Dellaert, S. N. C. AU - Boersma, K. F. AB - Abstract We use the OMI-QA4ECV-v1.1 NO2 tropospheric columns over the 10-year 2008–2017 period to confront satellite-based trends in NO2 concentrations to those from the state-of-the-art regional chemistry-transport model CHIMERE and to evaluate the bottom-up anthropogenic and biogenic NOx emissions in Europe. A focus is made for the 30 most populated urban areas in Europe. Over urban areas in Western Europe, except for coastal cities, OMI confirms the drop in the simulated CHIMERE NO2 tropospheric columns based on the latest country emission official reporting. OMI hardly shows significant negative trends over Central and Eastern Europe urban areas. Increasing biogenic emissions helps reconciling CHIMERE and OMI trends over urban areas in Central Europe and over rural areas, confirming the importance of accounting for non-anthropogenic emissions to assess long-term trends. Over Eastern Europe, our results question emission reductions estimated for particular sectors and in particular the road transport, public power, and industrial emissions. DA - 2021/// PY - 2021 ER - TY - JOUR TI - Do alternative inventories converge on the spatiotemporal representation of spring ammonia emissions in France? AU - Fortems-Cheiney, A. AU - Dufour, G. AU - Dufossé, K. AU - Couvidat, F. AU - Gilliot, J. M. AU - Siour, G. AU - Beekmann, M. AU - Foret, G. AU - Meleux, F. AU - Clarisse, L. AU - Coheur, P. F. AU - Van Damme, M. AU - Clerbaux, C. AU - Génermont, S. T2 - Atmos. Chem. Phys. DA - 2020/// PY - 2020 VL - 20 IS - 21 SP - 13481 EP - 13495 ER - TY - JOUR TI - Unaccounted variability in NH3 agricultural sources detected by IASI contributing to European spring haze episode AU - Fortems-Cheiney, A. AU - Dufour, G. AU - Hamaoui-Laguel, L. AU - Foret, G. AU - Siour, G. AU - Van Damme, M. AU - Meleux, F. AU - Coheur, P. F. AU - Clerbaux, C. AU - Clarisse, L. AU - Favez, O. AU - Wallasch, M. AU - Beekmann, M. C. Gl T2 - Geophysical Research Letters DA - 2016/// PY - 2016 SP - n/a EP - n/a KW - ammonia emissions IASI spreading practices 0365 Troposphere: composition and chemistry 0305 Aerosols and particles 0345 Pollution: urban and regional ER - TY - GEN TI - Understanding the Simulated Ammonia Increasing Trend from 2008 to 2015 over Europe with CHIMERE and Comparison with IASI Observations AU - Fortems-Cheiney, Audrey AU - Dufour, Gaëlle AU - Foret, Gilles AU - Siour, Guillaume AU - Van Damme, Martin AU - Coheur, Pierre-François AU - Clarisse, Lieven AU - Clerbaux, Cathy AU - Beekmann, Matthias DA - 2022/// PY - 2022 ER - TY - JOUR TI - Variational regional inverse modeling of reactive species emissions with PYVAR-CHIMERE-v2019 AU - Fortems-Cheiney, A. AU - Pison, I. AU - Broquet, G. AU - Dufour, G. AU - Berchet, A. AU - Potier, E. AU - Coman, A. AU - Siour, G. AU - Costantino, L. T2 - Geosci. Model Dev. DA - 2021/// PY - 2021 VL - 14 IS - 5 SP - 2939 EP - 2957 ER - TY - JOUR TI - Implementation of an incoherent broadband cavity-enhanced absorption spectroscopy technique in an atmospheric simulation chamber for in situ NO3 monitoring: characterization and validation for kinetic studies AU - Fouqueau, A. AU - Cirtog, M. AU - Cazaunau, M. AU - Pangui, E. AU - Zapf, P. AU - Siour, G. AU - Landsheere, X. AU - Méjean, G. AU - Romanini, D. AU - Picquet-Varrault, B. T2 - Atmos. Meas. Tech. DA - 2020/// PY - 2020 VL - 13 IS - 11 SP - 6311 EP - 6323 ER - TY - JOUR TI - Dust uplift potential in Central Sahel: an analysis based on 10 years of meteorological measurements at high temporal resolution AU - G. Bergametti, A. Maman, B. Marticorena, J.L. Rajot, B. Chatenet, A. Féron, C. Gaimoz, G. Siour, M. Coulibaly, I. Koné AU - Zakou, A. T2 - Journal of Geophysical Research: Atmospheres DA - 2017/// PY - 2017 ER - TY - JOUR TI - Parameterization of convective transport in the boundary layer and its impact on the representation of the diurnal cycle of wind and dust emissions AU - Hourdin, F. AU - Gueye, M. AU - Diallo, B. AU - Dufresne, J. L. AU - Escribano, J. AU - Menut, L. AU - Marticoréna, B. AU - Siour, G. AU - Guichard, F. T2 - Atmos. Chem. Phys. DA - 2015/// PY - 2015 VL - 15 IS - 12 SP - 6775 EP - 6788 ER - TY - JOUR TI - An investigation on the origin of regional springtime ozone episodes in the western Mediterranean AU - Kalabokas, P. AU - Hjorth, J. AU - Foret, G. AU - Dufour, G. AU - Eremenko, M. AU - Siour, G. AU - Cuesta, J. AU - Beekmann, M. T2 - Atmos. Chem. Phys. DA - 2017/// PY - 2017 VL - 17 IS - 6 SP - 3905 EP - 3928 ER - TY - JOUR TI - Experimental observation of fractional echoes AU - Karras, G. AU - Hertz, E. AU - Billard, F. AU - Lavorel, B. AU - Siour, G. AU - Hartmann, J. M. AU - Faucher, O. AU - Gershnabel, E. AU - Prior, Y. AU - Averbukh, I. S. T2 - Physical Review A AB - We report the observation of fractional echoes in a double-pulse excited nonlinear system. Unlike standard echoes, which appear periodically at delays which are integer multiples of the delay between the two exciting pulses, the fractional echoes appear at rational fractions of this delay. We discuss the mechanism leading to this phenomenon, and provide experimental demonstration of fractional echoes by measuring third harmonic generation in a thermal gas of CO2 molecules excited by a pair of femtosecond laser pulses. DA - 2016/// PY - 2016 VL - 94 IS - 3 SP - 6 KW - ALIGNMENT KW - BEAM KW - DYNAMICS KW - EVOLUTION KW - HARMONIC-GENERATION KW - LASER FIELDS KW - MANIPULATION KW - MOLECULES KW - REVIVALS KW - WAVE-PACKET ER - TY - JOUR TI - On the importance of the model representation of organic aerosol in simulations of the direct radiative effect of Siberian biomass burning aerosol in the eastern Arctic AU - Konovalov, Igor B. AU - Golovushkin, Nikolai A. AU - Beekmann, Matthias AU - Siour, Guillaume AU - Zhuravleva, Tatyana B. AU - Nasrtdinov, Ilmir M. AU - Kuznetsova, Irina N. T2 - Atmospheric Environment AB - Shortcomings and uncertainties in the model representation of atmospheric transformations (the aging) of organic aerosol (OA) have long been identified as one of the potential sources of considerable uncertainty in OA simulations with both global and regional models. However, the impact of this uncertainty on predictions of radiative and climate effects of both anthropogenic and biomass burning (BB) aerosol yet needs to be understood. This study examines the importance of the model representation of OA for simulating the direct radiative effect (DRE) of Siberian BB aerosol in the eastern Arctic. We employ a regional coupled chemistry-meteorology model and a global fire emission database to simulate the optical properties and DRE of BB aerosol emitted from intense Siberian fires in July 2016 and compare the DRE estimates that were obtained using two alternative representations of Siberian BB OA. One of them is a “default” OA representation that predicts very little secondary OA (SOA), and another involves a simple original OA parameterization that has been developed previously within the volatility basis set (VBS) framework and features a strong production of SOA. The simulations of the aerosol optical properties are evaluated against satellite observations of the aerosol optical depth (AOD) in Siberia and the Arctic as well as against values of the single scattering albedo derived from in situ observations of the aerosol absorption and scattering coefficients at four Arctic sites. While the simulations with the default OA representation are found to strongly underestimate AOD both in Siberia and the eastern Arctic, the use of the VBS parameterization considerably improves the agreement between the AOD simulations and observations in both regions. Simulations of the single scattering albedo are found to be overall rather adequate with both representations. Differences in the OA representations are found to result in major differences in the estimates of the DRE of Siberian BB aerosol in the eastern Arctic. Specifically, although the simulations with both representations predict that the DRE is predominantly negative at the top of the atmosphere (TOA), the magnitude of the mean DRE is found to be more than twice as large (6.0 W m−2) with the VBS parameterization than with the default OA representation (2.8 W m−2). An even larger difference (by a factor of 3.5) is found between the estimates of the DRE over the snow- or ice-covered areas. The different treatments of the BB OA evolution are associated also with considerably different contributions of black and brown carbon to the DRE estimates. Overall, our results indicate that model estimates of the DRE of Siberian BB aerosol in the eastern Arctic are strongly sensitive to the assumptions regarding the evolution of OA in Siberian BB plumes and that the SOA formation in these plumes is one of the major factors determining the magnitude of the radiative effects of Siberian BB aerosol in the real atmosphere. DA - 2023/// PY - 2023 VL - 309 SP - 119910 KW - Biomass burning Organic aerosol Radiative forcing Volatility basis set Microphysical model Mie theory calculations Radiative transfer ER - TY - GEN TI - Air Quality Degradation by Mineral Dust over Beijing, Chengdu and Shanghai Chinese Megacities AU - Lachatre, Mathieu AU - Foret, Gilles AU - Laurent, Benoit AU - Siour, Guillaume AU - Cuesta, Juan AU - Dufour, Gaëlle AU - Meng, Fan AU - Tang, Wei AU - Zhang, Qijie AU - Beekmann, Matthias DA - 2020/// PY - 2020 ER - TY - JOUR TI - The unintended consequence of SO2 and NO2 regulations over China: increase of ammonia levels and impact on PM2.5 concentrations AU - Lachatre, M. AU - Fortems-Cheiney, A. AU - Foret, G. AU - Siour, G. AU - Dufour, G. AU - Clarisse, L. AU - Clerbaux, C. AU - Coheur, P. F. AU - Van Damme, M. AU - Beekmann, M. T2 - Atmos. Chem. Phys. DA - 2019/// PY - 2019 VL - 19 IS - 10 SP - 6701 EP - 6716 ER - TY - JOUR TI - Modelling SO2 conversion into sulfates in the mid-troposphere with a 3D chemistry transport model: the case of Mount Etna's eruption on 12 April 2012 AU - Lachatre, M. AU - Mailler, S. AU - Menut, L. AU - Cholakian, A. AU - Sellitto, P. AU - Siour, G. AU - Guermazi, H. AU - Salerno, G. AU - Giammanco, S. T2 - Atmos. Chem. Phys. DA - 2022/// PY - 2022 VL - 22 IS - 20 SP - 13861 EP - 13879 ER - TY - JOUR TI - Impacts of regional climate change on air quality projections and associated uncertainties AU - Lacressonnière, Gwendoline AU - Foret, Gilles AU - Beekmann, Matthias AU - Siour, Guillaume AU - Engardt, Magnuz AU - Gauss, Michael AU - Watson, Laura AU - Andersson, Camilla AU - Colette, Augustin AU - Josse, Béatrice AU - Marécal, Virginie AU - Nyiri, Agnes AU - Vautard, Robert T2 - Climatic change AB - A 2-degree global warming is likely to affect the production, deposition, and transport of air pollutants, leading to impacts on air quality and health. In the present study we use an ensemble of four regional chemistry-transport models, driven by meteorological data from different climate models, to assess such changes and their uncertainties for PM2.5 and SOMO35. Changes and uncertainties are compared to the inter-model variability. We find that the impact of regional climate change on PM2.5, averaged over the model ensemble, ranges from −0.5 μg.m−3 to +1.3 μg.m−3 over Europe. It mainly results from changes in natural and biogenic emissions, such as desert dust, sea salt and biogenic VOCs. Statistically significant decreases in PM2.5 are found over southwestern Russia and Ukraine as well as an increase over Southern Spain. Modeled changes in summer ozone levels range from −1.7 to 1.6 ppbv. We find a smaller ensemble-mean evolution of SOMO35 as compared to inter-model variability. We also investigate the uncertainty due to inter-decadal variability and find that 10-year periods may not be sufficient to allow the detection of statistically significant change signals. DA - 2016/// PY - 2016 SP - 1 EP - 16 ER - TY - JOUR TI - Particulate matter air pollution in Europe in a +2 °C warming world AU - Lacressonnière, Gwendoline AU - Watson, Laura AU - Gauss, Michael AU - Engardt, Magnuz AU - Andersson, Camilla AU - Beekmann, Matthias AU - Colette, Augustin AU - Foret, Gilles AU - Josse, Béatrice AU - Marécal, Virginie AU - Nyiri, Agnes AU - Siour, Guillaume AU - Sobolowski, Stefan AU - Vautard, Robert T2 - Atmospheric Environment DA - 2017/// PY - 2017 VL - 154 SP - 129 EP - 140 KW - Air quality Chemical transport models Particulate matter Climate change IMPACT2C project ER - TY - GEN TI - 20th Century Changes of DOC and Its 14C Signature Archived in Caucasus Ice-Core: Implications for Past Sources of Organic Carbon Aerosol in South-Eastern Europe AU - Legrand, Michel AU - Preunkert, Susanne AU - Kutuzov, Stanislav AU - Siour, Guillaume AU - Mikhalenko, Vladimir AU - Dolgova, Ekaterina AU - Friedrich, Ronny AB - Abstract To reconstruct the history of organic carbon (OC) aerosol over south-eastern Europe, dissolved organic carbon (DOC) and its 14C signature (DO14C) were investigated along an ice core drilled at the Mount Elbrus (ELB) in Caucasus. In summer, compared to pre-1945 levels, the DOC concentrations increased by 45% after 1960, the mean DO14C depletion in recent ELB ice relative to atmospheric 14CO2 of 32% being attributed to fossil-fuel sources. DO14C content of ice deposited during the bomb-peak era (1955–1980) closely followed atmospheric 14CO2 changes caused by atmospheric nuclear tests, suggesting the living biosphere as the main biogenic source of DOC in summer in this region. ELB data contrast with those previously obtained in summer Alpine (western Europe) ice in which a post-1950 doubling of DOC was observed and attributed to enhanced emissions of organic compounds from vegetation in France. This regional difference is discussed with respect to changes of biogenic organic compound emissions in response to past change of use-land and global warming. ELB data document, for the first time, changes of DOC and DO14C in winter mountain ice showing an increase by 44% of DOC levels associated with a 14C signature being 47% lower than that of atmospheric 14CO2 in ELB ice deposited after 1960. The 14C winter ELB ice record followed atmospheric 14CO2 changes with a delay of ∼3 years, suggesting that remaining emissions from the living biosphere, together with a small contribution from wood burning, are the main biogenic sources of DOC in winter in this region. DA - 2024/// PY - 2024 ER - TY - JOUR TI - Oligomer formation in the troposphere: from experimental knowledge to 3-D modeling AU - Lemaire, V. AU - Coll, I. AU - Couvidat, F. AU - Mouchel-Vallon, C. AU - Seigneur, C. AU - Siour, G. T2 - Geosci. Model Dev. DA - 2016/// PY - 2016 VL - 9 IS - 4 SP - 1361 EP - 1382 ER - TY - GEN TI - Three-Dimensional Distribution of Biomass Burning Aerosols from Australian Wildfires Observed by TROPOMI Satellite Observations AU - Lemmouchi, Farouk AU - Cuesta, Juan AU - Eremenko, Maxim AU - Derognat, Claude AU - Siour, Guillaume AU - Dufour, Gaëlle AU - Sellitto, Pasquale AU - Turquety, Solène AU - Tran, Dung AU - Liu, Xiong AU - Zoogman, Peter AU - Lutz, Ronny AU - Loyola, Diego DA - 2022/// PY - 2022 ER - TY - JOUR TI - Echoes in Space and Time AU - Lin, Kang AU - Lu, Peifen AU - Ma, Junyang AU - Gong, Xiaochun AU - Song, Qiying AU - Ji, Qinying AU - Zhang, Wenbin AU - Zeng, Heping AU - Wu, Jian AU - Karras, Gabriel AU - Siour, Guillaume AU - Hartmann, Jean-Michel AU - Faucher, Olivier AU - Gershnabel, Erez AU - Prior, Yehiam AU - Averbukh, Ilya Sh T2 - Physical Review X DA - 2016/// PY - 2016 VL - 6 IS - 4 SP - 041056 ER - TY - JOUR TI - On the radiative impact of aerosols on photolysis rates: comparison of simulations and observations in the Lampedusa island during the ChArMEx/ADRIMED campaign AU - Mailler, S. AU - Menut, L. AU - di Sarra, A. G. AU - Becagli, S. AU - Di Iorio, T. AU - Bessagnet, B. AU - Briant, R. AU - Formenti, P. AU - Doussin, J. F. AU - Gomez-Amo, J. L. AU - Mallet, M. AU - Rea, G. AU - Siour, G. AU - Sferlazzo, D. M. AU - Traversi, R. AU - Udisti, R. AU - Turquety, S. T2 - Atmospheric Chemistry and Physics AB - The Mediterranean basin is characterized by large concentrations of aerosols from both natural and anthropogenic sources. These aerosols affect tropospheric photochemistry by modulating the photolytic rates. Three simulations of the atmospheric composition at basin scale have been performed with the CHIMERE chemistry-transport model for the period from 6 June to 15 July 2013 covered by the ADRIMED campaign, a campaign of intense measurements in the western Mediterranean basin. One simulation takes into account the radiative effect of the aerosols on photochemistry, the second one does not, and the third one is designed to quantify the model sensitivity to a bias in the ozone column. These simulations are compared to satellite and ground-based measurements, with a particular focus on the area of Lampedusa. Values of the aerosol optical depth (AOD) are obtained from the MODIS instrument on the AQUA and TERRA satellites as well as from stations in the AERONET network and from the MFRSR sun photometer deployed at Lampedusa. Additional measurements from instruments deployed at Lampedusa either permanently or exceptionally are used for other variables: MFRSR sun photometer for AOD, diode array spectrometer for actinic fluxes, LIDAR for the aerosol backscatter, sequential sampler for speciation of aerosol and Brewer spectrophotometer for the total ozone column. It is shown that CHIMERE has a significant ability to reproduce observed peaks in the AOD, which in Lampedusa are mainly due to dust outbreaks during the ADRIMED period, and that taking into account the radiative effect of the aerosols in CHIMERE considerably improves the ability of the model to reproduce the observed day-to-day variations of the photolysis rate of ozone to O-2 and O(D-1), J((OD)-D-1), and that of NO2 to NO and O(P-3), J(NO2). While in the case of J ((OD)-D-1) other variation factors such as the stratospheric ozone column are very important in representing correctly the day-to-day variations, the day-to-day variations of J(NO2) are captured almost completely by the model when the optical effects of the aerosols are taken into account. Finally, it is shown that the inclusion of the direct radiative effect of the aerosols in the CHIMERE model leads to reduced J((OD)-D-1) and J(NO2) values over all the simulation domain, which range from a few percents over continental Europe and the north-east Atlantic Ocean to about 20% close to and downwind from Saharan dust sources. The effect on the modelled ozone concentration is 2-fold: the effect of aerosols leads to reduced ozone concentrations over the Mediterranean Sea and continental Europe, close to the sources of NOx, but it also leads to increased ozone concentrations over remote areas such as the Sahara and the tropical Atlantic Ocean. DA - 2016/// PY - 2016 VL - 16 IS - 3 SP - 1219 EP - 1244 KW - ACCURATE SIMULATION KW - CHEMICAL-COMPOSITION KW - DUST KW - EURO-MEDITERRANEAN REGION KW - MASS CLOSURE KW - MODEL KW - OPTICAL-PROPERTIES KW - SA℡LITE DATA KW - STRATOSPHERIC OZONE KW - TROPOSPHERIC CHEMISTRY ER - TY - JOUR TI - CHIMERE-2017: from urban to hemispheric chemistry-transport modeling AU - Mailler, S. AU - Menut, L. AU - Khvorostyanov, D. AU - Valari, M. AU - Couvidat, F. AU - Siour, G. AU - Turquety, S. AU - Briant, R. AU - Tuccella, P. AU - Bessagnet, B. AU - Colette, A. AU - Létinois, L. AU - Markakis, K. AU - Meleux, F. T2 - Geosci. Model Dev. DA - 2017/// PY - 2017 VL - 10 IS - 6 SP - 2397 EP - 2423 ER - TY - JOUR TI - The CHIMERE v2020r1 online chemistry-transport model AU - Menut, L. AU - Bessagnet, B. AU - Briant, R. AU - Cholakian, A. AU - Couvidat, F. AU - Mailler, S. AU - Pennel, R. AU - Siour, G. AU - Tuccella, P. AU - Turquety, S. AU - Valari, M. T2 - Geosci. Model Dev. DA - 2021/// PY - 2021 VL - 14 IS - 11 SP - 6781 EP - 6811 ER - TY - JOUR TI - CHIMERE 2013: a model for regional atmospheric composition modelling AU - Menut, L. AU - Bessagnet, B. AU - Khvorostyanov, D. AU - Beekmann, M. AU - Blond, N. AU - Colette, A. AU - Coll, I. AU - Curci, G. AU - Foret, G. AU - Hodzic, A. AU - Mailler, S. AU - Meleux, F. AU - Monge, J. L. AU - Pison, I. AU - Siour, G. AU - Turquety, S. AU - Valari, M. AU - Vautard, R. AU - Vivanco, M. G. T2 - Geoscientific Model Development AB - Tropospheric trace gas and aerosol pollutants have adverse effects on health, environment and climate. In order to quantify and mitigate such effects, a wide range of processes leading to the formation and transport of pollutants must be considered, understood and represented in numerical models. Regional scale pollution episodes result from the combination of several factors: high emissions (from anthropogenic or natural sources), stagnant meteorological conditions, kinetics and efficiency of the chemistry and the deposition. All these processes are highly variable in time and space, and their relative contribution to the pollutants budgets can be quantified with chemistry-transport models. The CHIMERE chemistry-transport model is dedicated to regional atmospheric pollution event studies. Since it has now reached a certain level a maturity, the new stable version, CHIMERE 2013, is described to provide a reference model paper. The successive developments of the model are reviewed on the basis of published investigations that are referenced in order to discuss the scientific choices and to provide an overview of the main results. DA - 2013/// PY - 2013 VL - 6 IS - 4 SP - 981 EP - 1028 ER - TY - GEN TI - Impact of Lightning NOx Emissions on Atmospheric Composition and Meteorology in Africa and Europe AU - Menut, Laurent AU - Bessagnet, Bertrand AU - Mailler, Sylvain AU - Pennel, Romain AU - Siour, Guillaume DA - 2020/// PY - 2020 ER - TY - JOUR TI - Impact of lockdown measures to combat Covid-19 on air quality over western Europe AU - Menut, Laurent AU - Bessagnet, Bertrand AU - Siour, Guillaume AU - Mailler, Sylvain AU - Pennel, Romain AU - Cholakian, Arineh T2 - Science of The Total Environment AB - Recent studies based on observations have shown the impact of lockdown measures taken in various European countries to contain the Covid-19 pandemic on air quality. However, these studies are often limited to compare situations without and with lockdown measures, which correspond to different time periods and then under different meteorological conditions. We propose a modelling study with the WRF-CHIMERE modelling suite for March 2020, an approach allowing to compare atmospheric composition with and without lockdown measures without the biases of meteorological conditions. This study shows that the lockdown effect on atmospheric composition, in particular through massive traffic reductions, has been important for several short-lived atmospheric trace species, with a large reduction in NO2 concentrations, a lower reduction in Particulate Matter (PM) concentrations and a mitigated effect on ozone concentrations due to non-linear chemical effects. DA - 2020/// PY - 2020 VL - 741 SP - 140426 KW - COVID-19 Lockdown Chemistry-transport modelling Emissions scenario CHIMERE ER - TY - JOUR TI - Impact of Landes forest fires on air quality in France during the 2022 summer AU - Menut, L. AU - Cholakian, A. AU - Siour, G. AU - Lapere, R. AU - Pennel, R. AU - Mailler, S. AU - Bessagnet, B. T2 - Atmos. Chem. Phys. DA - 2023/// PY - 2023 VL - 23 IS - 13 SP - 7281 EP - 7296 ER - TY - JOUR TI - An alternative way to evaluate chemistry-transport model variability AU - Menut, L. AU - Mailler, S. AU - Bessagnet, B. AU - Siour, G. AU - Colette, A. AU - Couvidat, F. AU - Meleux, F. T2 - Geosci. Model Dev. DA - 2017/// PY - 2017 VL - 10 IS - 3 SP - 1199 EP - 1208 ER - TY - JOUR TI - Ozone and aerosol tropospheric concentrations variability analyzed using the ADRIMED measurements and the WRF and CHIMERE models AU - Menut, L. AU - Mailler, S. AU - Siour, G. AU - Bessagnet, B. AU - Turquety, S. AU - Rea, G. AU - Briant, R. AU - Mallet, M. AU - Sciare, J. AU - Formenti, P. AU - Meleux, F. T2 - Atmos. Chem. Phys. DA - 2015/// PY - 2015 VL - 15 IS - 11 SP - 6159 EP - 6182 ER - TY - GEN TI - Impact of Wildfires on Mineral Dust Emissions in Europe AU - Menut, Laurent AU - Siour, Guillaume AU - Bessagnet, Bertrand AU - Cholakian, Arineh AU - Pennel, Romain AU - Mailler, Sylvain AB - Abstract Mineral dust emissions mainly depend on soil erodibility and near-surface wind speeds. During biomass burning episodes, pyroconvection locally generates high surface wind speed and non-desert surfaces (such as forest and shrubs) are partially replaced by barren soil. These effects may induce additional mineral dust emission. However, they are generally not taken into account in chemistry-transport models since the biomass burning and mineral dust emissions are usually considered as independent processes. This may lead to an underestimation of the mineral dust emissions and therefore of the transported concentrations. In this study, this link is added in the CHIMERE chemistry-transport model. The summer of 2021 is modeled over Europe using the coupled WRF-CHIMERE system. Simulations with and without the link between emission processes are performed. Results are compared to observations such as surface measurements of ozone and particulate matter by EEA and aerosol optical depth by AERONET. With more emitted mineral dust, an effect is found on the whole meteorological and chemical system: wind, temperature, cloud, gas (such as ozone with a few ppb changes) and aerosol concentrations are changed. The effect does not appear to be very important but significant enough to have to be taken into account in future modeling. DA - 2022/// PY - 2022 ER - TY - JOUR TI - Modelling the mineralogical composition and solubility of mineral dust in the Mediterranean area with CHIMERE 2017r4 AU - Menut, L. AU - Siour, G. AU - Bessagnet, B. AU - Couvidat, F. AU - Journet, E. AU - Balkanski, Y. AU - Desboeufs, K. T2 - Geosci. Model Dev. DA - 2020/// PY - 2020 VL - 13 IS - 4 SP - 2051 EP - 2071 ER - TY - JOUR TI - Observations and regional modeling of aerosol optical properties, speciation and size distribution over Northern Africa and western Europe AU - Menut, L. AU - Siour, G. AU - Mailler, S. AU - Couvidat, F. AU - Bessagnet, B. T2 - Atmos. Chem. Phys. DA - 2016/// PY - 2016 VL - 16 IS - 20 SP - 12961 EP - 12982 ER - TY - JOUR TI - Study of the unknown HONO daytime source at a European suburban site during the MEGAPOLI summer and winter field campaigns AU - Michoud, V. AU - Colomb, A. AU - Borbon, A. AU - Miet, K. AU - Beekmann, M. AU - Camredon, M. AU - Aumont, B. AU - Perrier, S. AU - Zapf, P. AU - Siour, G. AU - Ait-Helal, W. AU - Afif, C. AU - Kukui, A. AU - Furger, M. AU - Dupont, J. C. AU - Haeffelin, M. AU - Doussin, J. F. T2 - Atmos. Chem. Phys. DA - 2014/// PY - 2014 VL - 14 IS - 6 SP - 2805 EP - 2822 ER - TY - JOUR TI - Radical budget analysis in a suburban European site during the MEGAPOLI summer field campaign AU - Michoud, V. AU - Kukui, A. AU - Camredon, M. AU - Colomb, A. AU - Borbon, A. AU - Miet, K. AU - Aumont, B. AU - Beekmann, M. AU - Durand-Jolibois, R. AU - Perrier, S. AU - Zapf, P. AU - Siour, G. AU - Ait-Helal, W. AU - Locoge, N. AU - Sauvage, S. AU - Afif, C. AU - Gros, V. AU - Furger, M. AU - Ancellet, G. AU - Doussin, J. F. T2 - Atmospheric Chemistry and Physics AB - Chemical Ionisation Mass Spectrometer measurements of hydroxyl radical (OH) and the sum of hydroperoxy and organic peroxy (HO2+RO2) radicals were conducted during the MEGAPOLI summer field campaign at the SIRTA observatory near Paris, France, in July 2009. OH and (HO2+RO2) showed a typical diurnal variation with averaged daytime maxima values around 5 x 10(6) and 1.2 x 10(8) molecule cm(-3), respectively. Simultaneously, a large number of ancillary measurements, such as NOx, O-3, HONO, HCHO and other VOCs were also conducted. These data provide an opportunity to assess our understanding of the radical chemistry in a suburban environment by comparing the radical observations to calculations. First, OH mixing ratios were estimated by a simple Photo Stationary State (PSS) calculation. PSS calculations overestimate the OH mixing ratio by 50%, especially at NOx mixing ratios lower than 10 ppb, suggesting that some loss processes were missing in the calculation at low NOx. Then, a photochemical box model simulation based on the Master Chemical Mechanism (MCM) and constrained by ancillary measurements was run to calculate radical concentrations. Three different modelling procedures were tested, varying the way the unconstrained secondary species were estimated, to cope with the unavoidable lack of their measurements. They led to significant differences in simulated radical concentrations. OH and (HO2+RO2) concentrations estimated by two selected model version were compared with measurements. These versions of the model were chosen because they lead, respectively, to the higher and lower simulated radical concentrations and are thus the two extremes versions. The box model showed better results than PSS calculations, with a slight overestimation of 12% and 5%, for OH and (HO2+RO2) respectively, in average for the reference model, and an overestimation of approximately 20% for OH and an underestimation for (HO2+RO2) for the other selected model version. Thus, we can conclude from our study that OH and (HO2+RO2) radical levels agree on average with observations within the uncertainty range. Finally, an analysis of the radical budget, on a daily basis (06:00-18:00 UTC), indicates that HONO photolysis (similar to 35%), O-3 photolysis (similar to 23%), and aldehydes and ketones photolysis (similar to 16% for formaldehyde and 18% for others) are the main radical initiation pathways. According to the MCM modelling, the reactions of RO2 with NO2 (similar to 19%), leading mainly to PAN formation, is a significant termination pathway in addition to the main net loss via reaction of OH with NO2 (similar to 50%). DA - 2012/// PY - 2012 VL - 12 IS - 24 SP - 11951 EP - 11974 ER - TY - JOUR TI - Past (1950-2017) and future (-2100) temperature and precipitation trends in Egypt AU - Mostafa, A. N. AU - Wheida, A. AU - El Nazer, M. AU - Adel, M. AU - El Leithy, L. AU - Siour, G. AU - Coman, A. AU - Borbon, A. AU - Magdy, A. W. AU - Omar, M. AU - Saad-Hussein, A. AU - Alfaro, S. C. T2 - Weather and Climate Extremes DA - 2019/// PY - 2019 VL - 26 ER - TY - JOUR TI - Source contributions to 2012 summertime aerosols in the Euro-Mediterranean region AU - Rea, G. AU - Turquety, S. AU - Menut, L. AU - Briant, R. AU - Mailler, S. AU - Siour, G. T2 - Atmos. Chem. Phys. DA - 2015/// PY - 2015 VL - 15 IS - 14 SP - 8013 EP - 8036 ER - TY - JOUR TI - Temporal trend of diarrhea morbidity rate with climate change: Egypt as a case study AU - Saad-Hussein, Amal AU - Helmy, Mona Adel AU - Ellaithy, Lamia Samir AU - Wheida, Ali AU - El Nazeer, Mostafa AU - Alfaro, Stephane C. AU - Siour, Guillaume AU - Borbon, Agnes AU - Abdel Wahab, Mohamed Magdy AU - Mostafa, Amira N. T2 - Environmental Science and Pollution Research AB - Many studies have detected a relationship between diarrhea morbidity rates with the changes in precipitation, temperature, floods, droughts, water shortage, etc. But, most of the authors were cautious in their studies, because of the lack of empirical climate-health data and there were large uncertainties in the future projections. The study aimed to refine the link between the morbidity rates of diarrhea in some Egyptian governorates representative of the three Egyptian geographical divisions with the meteorological changes that occurred in the 2006–2016 period for which the medical data are available, as a case study. Medical raw data was collected from the Information Centre Department of the Egyptian Ministry of Health and Population. The meteorological data of temperature and precipitation extremes were defined as data outside the 10th–90th percentile range of values of the period of study, and their analysis was done using a methodology similar to the one recommended by the WMO and integrated in the CLIMDEX software. Relationships between the morbidity rates of diarrhea in seven Egyptian governorates and the meteorological changes that occurred in the period 2006 to 2016 were analyzed using multiple linear regression analysis to identify the most effective meteorological factor that affects the trend of morbidity rate of diarrhea in each governorate. Statistical analysis revealed that some meteorological parameters can be used as predictors for morbidity rates of diarrhea in Cairo, Alexandria, and Gharbia, but not in Aswan, Behaira, and Dakahlia where the temporal evolution cannot be related with meteorology. In Red Sea, there was no temporal trend and no significant relationships between the diarrhea morbidity rate and meteorological parameters. The predictor meteorological parameters for morbidity rates of diarrhea were found to be depending on the geographic locations and infrastructures in these governorates. It was concluded that the meteorological data that can be used as predictors for the morbidity rate of diarrhea is depending on the geographical location and infrastructures of the target location. The socioeconomic levels as well as the infrastructures in the governorate must be considered confounders in future studies. DA - 2022/// PY - 2022 ER - TY - GEN TI - Anthropogenic NOx Emission Estimations over East China for 2015 and 2019 Using OMI Satellite Observations and the New Inverse Modeling System CIF-CHIMERE AU - Savas, Dilek AU - Dufour, Gaëlle AU - Coman, Adriana AU - Siour, Guillaume AU - Fortems-Cheiney, Audrey AU - Broquet, Grégoire AU - Pison, Isabelle AU - Berchet, Antoine AU - Bessagnet, Bertrand DA - 2023/// PY - 2023 ER - TY - JOUR TI - Bridging the scales in a eulerian air quality model to assess megacity export of pollution AU - Siour, G. AU - Colette, A. AU - Menut, L. AU - Bessagnet, B. AU - Coll, I. AU - Meleux, F. T2 - Environmental Modelling & Software AB - In Chemistry Transport Models (CTMs), spatial scale interactions are often represented through off-line coupling between large and small scale models. However, those nested configurations cannot give account of the impact of the local scale on its surroundings. This issue can be critical in areas exposed to air mass recirculation (sea breeze cells) or around regions with sharp pollutant emission gradients (large cities). Such phenomena can still be captured by the mean of adaptive gridding, two-way nesting or using model nudging, but these approaches remain relatively costly. We present here the development and the results of a simple alternative multi-scale approach making use of a horizontal stretched grid, in the Eulerian CTM CHIMERE. This method, called "stretching" or "zooming", consists in the introduction of local zooms in a single chemistry-transport simulation. It allows bridging online the spatial scales from the city (similar to 1 km resolution) to the continental area (similar to 50 km resolution). The CHIMERE model was run over a continental European domain, zoomed over the BeNeLux (Belgium, Netherlands and Luxembourg) area. We demonstrate that, compared with one-way nesting, the zooming method allows the expression of a significant feedback of the refined domain towards the large scale: around the city cluster of BeNeLuX, NO2 and O-3 scores are improved. NO2 variability around BeNeLux is also better accounted for, and the net primary pollutant flux transported back towards BeNeLux is reduced. Although the results could not be validated for ozone over BeNeLux, we show that the zooming approach provides a simple and immediate way to better represent scale interactions within a CTM, and constitutes a useful tool for apprehending the hot topic of megacities within their continental environment. (C) 2013 Elsevier Ltd. All rights reserved. DA - 2013/// PY - 2013 VL - 46 SP - 271 EP - 282 ER - TY - JOUR TI - Characterizing the surface microlayer in the Mediterranean Sea: trace metal concentrations and microbial plankton abundance AU - Tovar-Sanchez, A. AU - Rodriguez-Romero, A. AU - Engel, A. AU - Zäncker, B. AU - Fu, F. AU - Maranon, E. AU - Pérez-Lorenzo, M. AU - Bressac, M. AU - Wagener, T. AU - Triquet, S. AU - Siour, G. AU - Desboeufs, K. AU - Guieu, C. T2 - Biogeosciences DA - 2020/// PY - 2020 VL - 17 IS - 8 SP - 2349 EP - 2364 ER - TY - JOUR TI - Implementation of Aerosol-Cloud Interaction within WRF-CHIMERE Online Coupled Model: Evaluation and Investigation of the Indirect Radiative Effect from Anthropogenic Emission Reduction on the Benelux Union AU - Tuccella, Paolo AU - Menut, Laurent AU - Briant, Régis AU - Deroubaix, Adrien AU - Khvorostyanov, Dmitry AU - Mailler, Sylvain AU - Siour, Guillaume AU - Turquety, Solène T2 - Atmosphere DA - 2019/// PY - 2019 VL - 10 IS - 1 SP - 20 ER - TY - JOUR TI - APIFLAME v2.0 biomass burning emissions model: impact of refined input parameters on atmospheric concentration in Portugal in summer 2016 AU - Turquety, S. AU - Menut, L. AU - Siour, G. AU - Mailler, S. AU - Hadji-Lazaro, J. AU - George, M. AU - Clerbaux, C. AU - Hurtmans, D. AU - Coheur, P. F. T2 - Geosci. Model Dev. DA - 2020/// PY - 2020 VL - 13 IS - 7 SP - 2981 EP - 3009 ER - TY - JOUR TI - Impact of emissions and +2°C climate change upon future ozone and nitrogen dioxide over Europe AU - Watson, Laura AU - Lacressonnière, Gwendoline AU - Gauss, Michael AU - Engardt, Magnuz AU - Andersson, Camilla AU - Josse, Béatrice AU - Marécal, Virginie AU - Nyiri, Agnes AU - Sobolowski, Stefan AU - Siour, Guillaume AU - Szopa, Sophie AU - Vautard, Robert T2 - Atmospheric Environment AB - Abstract The evolution of ozone and nitrogen dioxide over Europe between the present day and a future period with a +2 °C global warming relative to the pre-industrial climate was studied using four offline chemistry transport models, each driven by a different climate model. Given the recent outcome of the COP21 negotiations, understanding the implications of climate change around the +2 °C threshold has never been more pressing or relevant. One of the objectives of this study was to show how changes in anthropogenic emissions and +2 °C climate change are expected to affect future air quality, which may have important implications upon human health. It was found that a +2 °C climate change alone was responsible for a modest, and not statistically significant, increase in surface O3 concentrations (of between −0.1–0.8 ppb in the summer averaged over the European domain) compared to the present climate. Two different emission scenarios were used for the future time period in order to provide an estimate of the extent of air pollution reductions that could occur if (a) all currently planned air quality legislation is implemented and (b) all maximum technologically feasible emission reductions are implemented. The results showed that summer O3 could be reduced by between 4 and 5 ppb under a current legislation scenario, with at least 3 ppb of further reductions under the maximum mitigated scenario. Calculations of summer ozone enhancement were used as a metric to analyse the results after having removed background ozone level changes. In conclusion it was found that future air quality on a regional scale will depend upon the implementation of effective emission reduction policy; the positive effects of which should not be hindered by a +2 °C global warming. DA - 2016/// PY - 2016 VL - 142 SP - 271 EP - 285 KW - Air quality Ozone Climate change Emission scenarios Chemistry transport models IMPACT2C ER - TY - JOUR TI - The impact of meteorological forcings on gas phase air pollutants over Europe AU - Watson, Laura AU - Lacressonnière, Gwendoline AU - Gauss, Michael AU - Engardt, Magnuz AU - Andersson, Camilla AU - Josse, Béatrice AU - Marécal, Virginie AU - Nyiri, Agnes AU - Sobolowski, Stefan AU - Siour, Guillaume AU - Vautard, Robert T2 - Atmospheric Environment AB - Abstract The impact of meteorological forcings on gas phase air pollutants (ozone and nitrogen dioxide) over Europe was studied using four offline chemistry transport models (CTMs) as part of the IMPACT2C project. This study uses long (20- and 30-year) simulations to evaluate the present-day performance of the CTMs, which is a necessary first step before undertaking any analysis of future air quality impacts. Two sets of meteorological forcings were used for each model: reanalysis of past observation data (ERA-Interim) and Global Climate Model (GCM) output. The results for the simulations forced by reanalysis data were assessed in relation to AirBase v7 measurement data, and it was determined that all four models slightly overpredict annual O3 values (mean biases range between 0.7 and 6.6 ppb) and three out of the four models underpredict observed annual NO2 (mean biases range between −3.1 and −5.2 ppb). The simulations forced by climate models result in spatially averaged monthly concentrations of O3 that are generally between 0 and 5 ppb higher than the values obtained from simulations forced by reanalysis data; therefore it was concluded that the use of climate models introduces an additional bias to the results, but this bias tends not to be significant in the majority of cases. The bias in O3 results appears to be correlated mainly to differences in temperature and boundary layer height between the two types of simulations, whereas the less significant bias in NO2 is negatively correlated to temperature and boundary layer height. It is also clear that the selection of chemical boundary conditions is an important factor in determining the variability of O3 model results. These results will be used as a baseline for the interpretation of future work, which will include an analysis of future climate scenarios upon European air quality. DA - 2015/// PY - 2015 VL - 119 SP - 240 EP - 257 KW - Air quality Ozone Reanalysis forcings Global climate model Chemistry transport model ER - TY - JOUR TI - Formation of organic aerosol in the Paris region during the MEGAPOLI summer campaign: evaluation of the volatility-basis-set approach within the CHIMERE model AU - Zhang, Q. J. AU - Beekmann, M. AU - Drewnick, F. AU - Freutel, F. AU - Schneider, J. AU - Crippa, M. AU - Prevot, A. S. H. AU - Baltensperger, U. AU - Poulain, L. AU - Wiedensohler, A. AU - Sciare, J. AU - Gros, V. AU - Borbon, A. AU - Colomb, A. AU - Michoud, V. AU - Doussin, J. F. AU - van der Gon, H. A. C. Denier AU - Haeffelin, M. AU - Dupont, J. C. AU - Siour, G. AU - Petetin, H. AU - Bessagnet, B. AU - Pandis, S. N. AU - Hodzic, A. AU - Sanchez, O. AU - Honore, C. AU - Perrussel, O. T2 - Atmospheric Chemistry and Physics AB - Simulations with the chemistry transport model CHIMERE are compared to measurements performed during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) summer campaign in the Greater Paris region in July 2009. The volatility-basis-set approach (VBS) is implemented into this model, taking into account the volatility of primary organic aerosol (POA) and the chemical aging of semi-volatile organic species. Organic aerosol is the main focus and is simulated with three different configurations with a modified treatment of POA volatility and modified secondary organic aerosol (SOA) formation schemes. In addition, two types of emission inventories are used as model input in order to test the uncertainty related to the emissions. Predictions of basic meteorological parameters and primary and secondary pollutant concentrations are evaluated, and four pollution regimes are defined according to the air mass origin. Primary pollutants are generally overestimated, while ozone is consistent with observations. Sulfate is generally overestimated, while ammonium and nitrate levels are well simulated with the refined emission data set. As expected, the simulation with non-volatile POA and a single-step SOA formation mechanism largely overestimates POA and underestimates SOA. Simulation of organic aerosol with the VBS approach taking into account the aging of semi-volatile organic compounds (SVOC) shows the best correlation with measurements. High-concentration events observed mostly after long-range transport are well reproduced by the model. Depending on the emission inventory used, simulated POA levels are either reasonable or underestimated, while SOA levels tend to be overestimated. Several uncertainties related to the VBS scheme (POA volatility, SOA yields, the aging parameterization), to emission input data, and to simulated OH levels can be responsible for this behavior. Despite these uncertainties, the implementation of the VBS scheme into the CHIMERE model allowed for much more realistic organic aerosol simulations for Paris during summertime. The advection of SOA from outside Paris is mostly responsible for the highest OA concentration levels. During advection of polluted air masses from northeast (Benelux and Central Europe), simulations indicate high levels of both anthropogenic and biogenic SOA fractions, while biogenic SOA dominates during periods with advection from Southern France and Spain. DA - 2013/// PY - 2013 VL - 13 IS - 11 SP - 5767 EP - 5790 ER - TY - JOUR TI - Diurnal cycle of coastal anthropogenic pollutant transport over southern West Africa during the DACCIWA campaign AU - Deroubaix, Adrien AU - Menut, Laurent AU - Flamant, Cyrille AU - Brito, Joel AU - Denjean, Cyrielle AU - Dreiling, Volker AU - Fink, Andreas AU - Jambert, Corinne AU - Kalthoff, Norbert AU - Knippertz, Peter AU - Ladkin, Russ AU - Mailler, Sylvain AU - Maranan, Marlon AU - Pacifico, Federica AU - Piguet, Bruno AU - Siour, Guillaume AU - Turquety, Solène T2 - Atmospheric Chemistry and Physics AB - During the monsoon season, pollutants emitted by large coastal cities and biomass burning plumes originating from central Africa have complex transport pathways over southern West Africa (SWA). The Dynamics–Aerosol–Chemistry–Cloud Interactions in West Africa (DACCIWA) field campaign has provided numerous dynamical and chemical measurements in and around the super-site of Savè in Benin (≈185 km away from the coast), which allows quantification of the relative contribution of advected pollutants. Through the combination of in situ ground measurements with aircraft, radio-sounding, satellite, and high-resolution chemistry-transport modeling with the CHIMERE model, the source attribution and transport pathways of pollutants inland (here, NOx and CO) are carefully analyzed for the 1–7 July 2016 period. The relative contributions of different sources (i.e., emissions from several large coastal cities) to the air quality in Savè are characterized. It is shown that a systematic diurnal cycle exists with high surface concentrations of pollutants from 18:00 to 22:00 UTC. This evening peak is attributed to pollution transport from the coastal city of Cotonou (Benin). Numerical model experiments indicate that the anthropogenic pollutants are accumulated during the day close to the coast and transported northward as soon as the daytime convection in the atmospheric boundary layer ceases after 16:00 UTC, reaching 8∘ N at 21:00 UTC. When significant biomass burning pollutants are transported into continental SWA, they are mixed with anthropogenic pollutants along the coast during the day, and this mixture is then transported northward. At night, most of the coastal anthropogenic plumes are transported within the planetary boundary layer (below about 500 m above ground level), whereas the biomass burning pollutants are mostly transported above it, thus generally not impacting ground level air quality. DA - 2019/01/14/ PY - 2019 DO - 10.5194/acp-19-473-2019 DP - Copernicus Online Journals VL - 19 IS - 1 SP - 473 EP - 497 LA - English SN - 1680-7316 UR - https://acp.copernicus.org/articles/19/473/2019/ Y2 - 2024/03/30/12:53:28 L1 - https://acp.copernicus.org/articles/19/473/2019/acp-19-473-2019.pdf ER - TY - JOUR TI - What is the relative impact of nudging and online coupling on meteorological variables, pollutant concentrations and aerosol optical properties? AU - Menut, L. AU - Bessagnet, B. AU - Cholakian, A. AU - Siour, G. AU - Mailler, S. AU - Pennel, R. T2 - Geosci. Model Dev. DA - 2024/05/07/ PY - 2024 DO - 10.5194/gmd-17-3645-2024 VL - 17 IS - 9 SP - 3645 EP - 3665 J2 - Geosci. Model Dev. SN - 1991-9603 UR - https://gmd.copernicus.org/articles/17/3645/2024/ L4 - https://gmd.copernicus.org/articles/17/3645/2024/gmd-17-3645-2024.pdf ER - TY - JOUR TI - The CHIMERE chemistry-transport model v2023r1 AU - Menut, Laurent AU - Cholakian, Arineh AU - Pennel, Romain AU - Siour, Guillaume AU - Mailler, Sylvain AU - Valari, Myrto AU - Lugon, Lya AU - Meurdesoif, Yann T2 - Geoscientific Model Development AB - A new version of the CHIMERE model is presented. This version contains both computational and physico-chemical changes. The computational changes make it easy to choose the variables to be extracted as a result, including values of maximum sub-hourly concentrations. Performance tests show that the model is 1.5 to 2 times faster than the previous version for the same setup. Processes such as turbulence, transport schemes and dry deposition have been modified and updated. Optimization was also performed for the management of emissions such as anthropogenic and mineral dust. The impact of fires on wind speed, soil properties and leaf area index (LAI) was added. Pollen emissions, transport and deposition were added for birch, ragweed, olive and grass. The model is validated with a simulation covering Europe with a 60 km × 60 km resolution and the entire year of 2019. Results are compared to various measurements, and statistical scores show that the model provides better results than the previous versions. DA - 2024/07/17/ PY - 2024 DO - 10.5194/gmd-17-5431-2024 DP - Copernicus Online Journals VL - 17 IS - 14 SP - 5431 EP - 5457 LA - English SN - 1991-959X UR - https://gmd.copernicus.org/articles/17/5431/2024/ Y2 - 2024/07/17/11:09:36 L1 - https://gmd.copernicus.org/articles/17/5431/2024/gmd-17-5431-2024.pdf ER - TY - JOUR TI - NOx emissions in France in 2019–2021 as estimated by the high-spatial-resolution assimilation of TROPOMI NO2 observations AU - Plauchu, R. AU - Fortems-Cheiney, A. AU - Broquet, G. AU - Pison, I. AU - Berchet, A. AU - Potier, E. AU - Dufour, G. AU - Coman, A. AU - Savas, D. AU - Siour, G. AU - Eskes, H. T2 - Atmos. Chem. Phys. DA - 2024/07/19/ PY - 2024 DO - 10.5194/acp-24-8139-2024 VL - 24 IS - 14 SP - 8139 EP - 8163 J2 - Atmos. Chem. Phys. SN - 1680-7324 UR - https://acp.copernicus.org/articles/24/8139/2024/ L4 - https://acp.copernicus.org/articles/24/8139/2024/acp-24-8139-2024.pdf ER - TY - JOUR TI - Modelling of atmospheric concentrations of fungal spores: a 2-year simulation over France using CHIMERE AU - Vida, Matthieu AU - Foret, Gilles AU - Siour, Guillaume AU - Couvidat, Florian AU - Favez, Olivier AU - Uzu, Gaelle AU - Cholakian, Arineh AU - Conil, Sébastien AU - Beekmann, Matthias AU - Jaffrezo, Jean-Luc T2 - Atmospheric Chemistry and Physics AB - Fungal spore organic aerosol emissions have been recognised as a significant source of particulate matter as PM10; however, they are not widely considered in current air quality models. In this work, we have implemented the parameterisation of fungal spore organic aerosol (OA) emissions introduced by Heald and Spracklen (2009) (H&S) and further modified by Hoose et al. (2010) in the CHIMERE regional chemistry-transport model. This simple parameterisation is based on two variables, leaf area index (LAI) and specific humidity. We have validated the geographical and temporal representativeness of this parameterisation on a large scale by using yearly polyol observations and primary biogenic organic aerosol factors from positive matrix factorisation (PMF) analysis at 11 French measurement sites. For a group of sites in northern and eastern France, the seasonal variation of fungal spore emissions, displaying large summer and small winter values, is correctly depicted. However, the H&S parameterisation fails to capture fungal spore concentrations for a smaller group of Mediterranean sites with less data availability in terms of both absolute values and seasonal variability, leading to strong negative biases, especially during the autumn and winter seasons. Two years of CHIMERE simulations with the H&S parameterisation have shown a significant contribution of fungal spore OA to PM10 mass, which is lower than 10 % during winter and reaches up to 20 % during summer in high-emission zones, especially over large forested areas. In terms of contributions to organic matter (OM) concentrations, the simulated fungal spore contribution in autumn is as high as 40 % and reaches at most 30 % of the OM for the other seasons. As a conclusion, the fungal spore OA contribution to the total OM concentrations is shown to be substantial enough to be considered a major PM10 fraction and should then be included in state-of-the-art chemistry-transport models. DA - 2024/09/23/ PY - 2024 DO - 10.5194/acp-24-10601-2024 DP - Copernicus Online Journals VL - 24 IS - 18 SP - 10601 EP - 10615 LA - English SN - 1680-7316 ST - Modelling of atmospheric concentrations of fungal spores UR - https://acp.copernicus.org/articles/24/10601/2024/ Y2 - 2024/09/24/08:52:20 L1 - https://acp.copernicus.org/articles/24/10601/2024/acp-24-10601-2024.pdf ER -