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
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 (BB...
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ftcopernicus:oai:publications.copernicus.org:acp73077 2023-05-15T13:07:12+02:00 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 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 2019-04-12 application/pdf https://doi.org/10.5194/acp-19-4963-2019 https://www.atmos-chem-phys.net/19/4963/2019/ eng eng doi:10.5194/acp-19-4963-2019 https://www.atmos-chem-phys.net/19/4963/2019/ eISSN: 1680-7324 Text 2019 ftcopernicus https://doi.org/10.5194/acp-19-4963-2019 2019-12-24T09:49:18Z 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 continent, the presence of BBA is shown to significantly decrease the net surface SW flux, through direct and semi-direct effects, which is compensated by a decrease (monthly mean) in sensible heat fluxes ( −25 W m −2 ) and surface land temperature ( −1.5 ∘ C) over Angola, Zambia and the Democratic Republic of the Congo, notably. The surface cooling and the lower tropospheric heating decrease the continental planetary boundary layer height by about ∼200 m. Text Aerosol Robotic Network Copernicus Publications: E-Journals Merra ENVELOPE(12.615,12.615,65.816,65.816) Atmospheric Chemistry and Physics 19 7 4963 4990 |
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Open Polar |
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Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
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 continent, the presence of BBA is shown to significantly decrease the net surface SW flux, through direct and semi-direct effects, which is compensated by a decrease (monthly mean) in sensible heat fluxes ( −25 W m −2 ) and surface land temperature ( −1.5 ∘ C) over Angola, Zambia and the Democratic Republic of the Congo, notably. The surface cooling and the lower tropospheric heating decrease the continental planetary boundary layer height by about ∼200 m. |
format |
Text |
author |
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 |
spellingShingle |
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 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 |
author_facet |
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 |
author_sort |
Mallet, Marc |
title |
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 |
title_short |
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 |
title_full |
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 |
title_fullStr |
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 |
title_full_unstemmed |
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 |
title_sort |
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 |
publishDate |
2019 |
url |
https://doi.org/10.5194/acp-19-4963-2019 https://www.atmos-chem-phys.net/19/4963/2019/ |
long_lat |
ENVELOPE(12.615,12.615,65.816,65.816) |
geographic |
Merra |
geographic_facet |
Merra |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-19-4963-2019 https://www.atmos-chem-phys.net/19/4963/2019/ |
op_doi |
https://doi.org/10.5194/acp-19-4963-2019 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
19 |
container_issue |
7 |
container_start_page |
4963 |
op_container_end_page |
4990 |
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1766040153426493440 |