Articles | Volume 14, issue 4 
            
                
                    
            
            
            https://doi.org/10.5194/gmd-14-2221-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-14-2221-2021
                    © Author(s) 2021. This work is distributed under 
the Creative Commons Attribution 4.0 License.
                the Creative Commons Attribution 4.0 License.
Using the Després and Lagoutière (1999) antidiffusive transport scheme: a promising and novel method against excessive vertical diffusion in chemistry-transport models
Sylvain Mailler
CORRESPONDING AUTHOR
                                            
                                    
                                            LMD/IPSL, École Polytechnique, Institut Polytechnique de Paris, ENS, PSL Research University, Sorbonne Université, CNRS, Palaiseau France
                                        
                                    
                                            École des Ponts-ParisTech, Marne-la-Vallée, France
                                        
                                    Romain Pennel
                                            LMD/IPSL, École Polytechnique, Institut Polytechnique de Paris, ENS, PSL Research University, Sorbonne Université, CNRS, Palaiseau France
                                        
                                    Laurent Menut
                                            LMD/IPSL, École Polytechnique, Institut Polytechnique de Paris, ENS, PSL Research University, Sorbonne Université, CNRS, Palaiseau France
                                        
                                    Mathieu Lachâtre
                                            LMD/IPSL, École Polytechnique, Institut Polytechnique de Paris, ENS, PSL Research University, Sorbonne Université, CNRS, Palaiseau France
                                        
                                    
                                            currently at: Aria Technologies, Boulogne-Billancourt, France
                                        
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                                                In this study, we evaluate the present state of modelling lightning flashes over the Northern Hemisphere, using the classical CTH (cloud-top height) scheme and the ICEFLUX scheme with the CHIMERE model. Our study provides a comprehensive 3D comparison of model outputs to assess the robustness and applicability of these schemes. An improvement in O3 distribution in the tropical free troposphere is observed due to inclusion of LNOx (nitrogen oxide emissions from lightning) in the model. Inclusion of LNOx also reduces the lifetime of trace gas CH4.
                                            
                                            
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                                                We propose two explicit expressions to calculate the settling speed of solid atmospheric particles with prolate spheroidal shapes. The first formulation is based on theoretical arguments only, while the second one is based on computational fluid dynamics calculations. We show that the first method is suitable for virtually all atmospheric aerosols, provided their shape can be adequately described as a prolate spheroid, and we provide an implementation of the first method in AerSett v2.0.2.
                                            
                                            
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                                                This study is about the modelling of the atmospheric composition in Europe during the summer of 2022, when massive wildfires were observed. It is a sensitivity study dedicated to the relative impacts of two modelling processes that are able to modify the meteorology used for the calculation of the atmospheric chemistry and transport of pollutants.
                                            
                                            
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                                        Laurent Menut
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                                                This study analyzes forecasts that were made in 2021 to help trigger measurements during the CADDIWA experiment. The WRF and CHIMERE models were run each day, and the first goal is to quantify the variability of the forecast as a function of forecast leads and forecast location. The possibility of using the different leads as an ensemble is also tested. For some locations, the correlation scores are better with this approach. This could be tested on operational forecast chains in the future.
                                            
                                            
                                        Laurent Menut, Arineh Cholakian, Guillaume Siour, Rémy Lapere, Romain Pennel, Sylvain Mailler, and Bertrand Bessagnet
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                                                This study is about the wildfires occurring in France during the summer 2022. We study the forest fires that took place in the Landes during the summer of 2022. We show the direct impact of these fires on the air quality, especially downstream of the smoke plume towards the Paris region. We quantify the impact of these fires on the pollutants peak concentrations and the possible exceedance of thresholds.
                                            
                                            
                                        Danny M. Leung, Jasper F. Kok, Longlei Li, Gregory S. Okin, Catherine Prigent, Martina Klose, Carlos Pérez García-Pando, Laurent Menut, Natalie M. Mahowald, David M. Lawrence, and Marcelo Chamecki
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                                        Sylvain Mailler, Laurent Menut, Arineh Cholakian, and Romain Pennel
                                    Geosci. Model Dev., 16, 1119–1127, https://doi.org/10.5194/gmd-16-1119-2023, https://doi.org/10.5194/gmd-16-1119-2023, 2023
                                    Short summary
                                    Short summary
                                            
                                                Large or even 
                                            
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Rémy Lapere, Nicolás Huneeus, Sylvain Mailler, Laurent Menut, and Florian Couvidat
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                                        Mathieu Lachatre, Sylvain Mailler, Laurent Menut, Arineh Cholakian, Pasquale Sellitto, Guillaume Siour, Henda Guermazi, Giuseppe Salerno, and Salvatore Giammanco
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                                        Juan Cuesta, Lorenzo Costantino, Matthias Beekmann, Guillaume Siour, Laurent Menut, Bertrand Bessagnet, Tony C. Landi, Gaëlle Dufour, and Maxim Eremenko
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                                        Adrien Deroubaix, Laurent Menut, Cyrille Flamant, Peter Knippertz, Andreas H. Fink, Anneke Batenburg, Joel Brito, Cyrielle Denjean, Cheikh Dione, Régis Dupuy, Valerian Hahn, Norbert Kalthoff, Fabienne Lohou, Alfons Schwarzenboeck, Guillaume Siour, Paolo Tuccella, and Christiane Voigt
                                    Atmos. Chem. Phys., 22, 3251–3273, https://doi.org/10.5194/acp-22-3251-2022, https://doi.org/10.5194/acp-22-3251-2022, 2022
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                                                During the summer monsoon in West Africa, pollutants emitted in urbanized areas modify cloud cover and precipitation patterns. We analyze these patterns with the WRF-CHIMERE model, integrating the effects of aerosols on meteorology, based on the numerous observations provided by the Dynamics-Aerosol-Climate-Interactions campaign. This study adds evidence to recent findings that increased pollution levels in West Africa delay the breakup time of low-level clouds and reduce precipitation.
                                            
                                            
                                        Laurent Menut, Bertrand Bessagnet, Régis Briant, Arineh Cholakian, Florian Couvidat, Sylvain Mailler, Romain Pennel, Guillaume Siour, Paolo Tuccella, Solène Turquety, and Myrto Valari
                                    Geosci. Model Dev., 14, 6781–6811, https://doi.org/10.5194/gmd-14-6781-2021, https://doi.org/10.5194/gmd-14-6781-2021, 2021
                                    Short summary
                                    Short summary
                                            
                                                The CHIMERE chemistry-transport model is presented in its new version, V2020r1. Many changes are proposed compared to the previous version. These include online modeling, new parameterizations for aerosols, new emissions schemes, a new parameter file format, the subgrid-scale variability of urban concentrations and new transport schemes.
                                            
                                            
                                        Yonatan Givon, Douglas Keller Jr., Vered Silverman, Romain Pennel, Philippe Drobinski, and Shira Raveh-Rubin
                                    Weather Clim. Dynam., 2, 609–630, https://doi.org/10.5194/wcd-2-609-2021, https://doi.org/10.5194/wcd-2-609-2021, 2021
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                                                Mistral wind is a renowned phenomenon in the Mediterranean, yet its large-scale controlling mechanisms have not been systematically mapped. Here, using a new mistral database for 1981–2016, the upper-tropospheric flow patterns are classified by a self-organizing map algorithm, resulting in 16 distinct patterns related to Rossby wave life cycles. Each pattern has unique surface impact, having implications to understanding mistral predictability, air–sea interaction and their future projections.
                                            
                                            
                                        Sanhita Ghosh, Shubha Verma, Jayanarayanan Kuttippurath, and Laurent Menut
                                    Atmos. Chem. Phys., 21, 7671–7694, https://doi.org/10.5194/acp-21-7671-2021, https://doi.org/10.5194/acp-21-7671-2021, 2021
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                                                Wintertime direct radiative perturbation due to black carbon (BC) aerosols was assessed over the Indo-Gangetic Plain with an efficiently modelled BC distribution. The atmospheric radiative warming due to BC was about 50–70 % larger than surface cooling. Compared to the atmosphere without BC, for which a net cooling at the top of the atmosphere was exhibited, enhanced atmospheric radiative warming by 2–3 times and a reduction in surface cooling by 10–20 % were found due to BC.
                                            
                                            
                                        Rémy Lapere, Laurent Menut, Sylvain Mailler, and Nicolás Huneeus
                                    Atmos. Chem. Phys., 21, 6431–6454, https://doi.org/10.5194/acp-21-6431-2021, https://doi.org/10.5194/acp-21-6431-2021, 2021
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                                    Short summary
                                            
                                                Based on modeling, the transport dynamics of ozone and fine particles in central Chile are investigated. Santiago emissions are found to influence air quality along a 1000 km plume as far as Argentina and northern Chile. In turn, emissions outside the metropolis contribute significantly to its recorded particles concentration. Emissions of precursors from Santiago are found to lead to the formation of a persistent ozone bubble in altitude, a phenomenon which is described for the first time.
                                            
                                            
                                        Bertrand Bessagnet, Laurent Menut, and Maxime Beauchamp
                                    Geosci. Model Dev., 14, 91–106, https://doi.org/10.5194/gmd-14-91-2021, https://doi.org/10.5194/gmd-14-91-2021, 2021
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                                                This paper presents a new interpolator useful for geophysics applications. It can explore N-dimensional meshes, grids or look-up tables. The code accepts irregular but structured grids. Written in Fortran, it is easy to implement in existing codes and very fast and portable. We have compared it with a Python library. Python is convenient but suffers from portability and is sometimes not optimized enough. As an application case, this method is applied to atmospheric sciences.
                                            
                                            
                                        Mathieu Lachatre, Sylvain Mailler, Laurent Menut, Solène Turquety, Pasquale Sellitto, Henda Guermazi, Giuseppe Salerno, Tommaso Caltabiano, and Elisa Carboni
                                    Geosci. Model Dev., 13, 5707–5723, https://doi.org/10.5194/gmd-13-5707-2020, https://doi.org/10.5194/gmd-13-5707-2020, 2020
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                                                Excessive numerical diffusion is a major limitation in the representation of long-range transport in atmospheric models. In the present study, we focus on excessive diffusion in the vertical direction. We explore three possible ways of addressing this problem: increased vertical resolution, an advection scheme with anti-diffusive properties and more accurate representation of vertical wind. This study focused on a particular volcanic eruption event to improve atmospheric transport modeling.
                                            
                                            
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                Short summary
            Representing the advection of thin polluted plumes in numerical models is a challenging task since these models usually tend to excessively diffuse these plumes in the vertical direction. This numerical diffusion process is the cause of major difficulties in representing such dense and thin polluted plumes in numerical models. We propose here, and test in an academic framework, a novel method to solve this problem through the use of an antidiffusive advection scheme in the vertical direction.
            Representing the advection of thin polluted plumes in numerical models is a challenging task...