Simulation of the transport, vertical distribution, optical properties and radiative impact of smoke aerosols with the ALADIN regional climate model during the ORACLES-2016 and LASIC experiments

• Published in: Atmospheric Chemistry and Physics
• Main Authors: Mallet, Marc, Nabat, Pierre, Zuidema, Paquita, Redemann, Jens, Sayer, Andrew Mark, Stengel, Martin, Schmidt, Sebastian, Cochrane, Sabrina, Burton, Sharon, Ferrare, Richard, Meyer, Kerry, Saide, Pablo, Jethva, Hiren, Torres, Omar, Wood, Robert, Saint Martin, David, Roehrig, Romain, Hsu, Christina, Formenti, Paola
• Other Authors: Chercheur indépendant, Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS), Rosenstiel School of Marine and Atmospheric Science (RSMAS), University of Miami Coral Gables, NASA Langley Research Center Hampton (LaRC), NASA Goddard Space Flight Center (GSFC), Center for Global and Regional Environmental Research (CGRER), University of Iowa Iowa City, Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; Aerosol Robotic Network
• Online Access: https://hal.science/hal-02352584; https://hal.science/hal-02352584/document; https://hal.science/hal-02352584/file/Mallet_acp-19-4963-2019-includes-suppl.pdf; https://doi.org/10.5194/acp-19-4963-2019

International audience Estimates of the direct radiative effect (DRE) from absorbing smoke aerosols over the southeast Atlantic Ocean (SAO) require simulation of the microphysical and optical properties of stratocumulus clouds as well as of the altitude and shortwave (SW) optical properties of biomass burning aerosols (BBAs). In this study, we take advantage of the large number of observations acquired during the ObseRvations of Aerosols above Clouds and their intEractionS (ORACLES-2016) and Layered Atlantic Smoke Interactions with Clouds (LASIC) projects during September 2016 and compare them with datasets from the ALADIN-Climate (Aire Limitée Adaptation dynamique Développement InterNational) regional model. The model provides a good representation of the liquid water path but the low cloud fraction is underestimated compared to satellite data. The modeled total-column smoke aerosol optical depth (AOD) and above-cloud AOD are consistent (∼ 0.7 over continental sources and ∼ 0.3 over the SAO at 550 nm) with the Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2), Ozone Monitoring Instrument (OMI) or Moderate Resolution Imaging Spectroradiometer (MODIS) data. The simulations indicate smoke transport over the SAO occurs mainly between 2 and 4 km, consistent with surface and aircraft lidar observations. The BBA single scattering albedo is slightly overestimated compared to the Aerosol Robotic Network (AERONET) and more significantly when compared to Ascension Island surface observations. The difference could be due to the absence of internal mixing treatment in the ALADIN-Climate model. The SSA overestimate leads to an underestimation of the simulated SW radiative heating compared to ORACLES data. ALADIN-Climate simulates a positive (monthly mean) SW DRE of about +6 W m −2 over the SAO (20 • S-10 • N and 10 • W-20 • E) at the top of the atmosphere and in all-sky conditions. Over the conti-Published by Copernicus Publications on behalf of the European Geosciences Union. 4964 M. ...