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1. Variability of the Aerosol Content in the Tropical Lower Stratosphere from 2013 to 2019: Evidence of Volcanic Eruption Impacts

Author

Mariam Tidiga, Gwenaël Berthet, Fabrice Jégou, Corinna Kloss, Nelson Bègue, Jean-Paul Vernier, Jean-Baptiste Renard, Adriana Bossolasco, Lieven Clarisse, Ghassan Taha, Thierry Portafaix, Terry Deshler, Frank G. Wienhold, Sophie Godin-Beekmann, Guillaume Payen, Jean-Marc Metzger, Valentin Duflot, and Nicolas Marquestaut

Subjects
stratospheric aerosols, volcanic eruptions, satellite, balloon-borne observations, lidar, modelling, Meteorology. Climatology, QC851-999
Abstract

This paper quantifies the tropical stratospheric aerosol content as impacted by volcanic events over the 2013–2019 period. We use global model simulations by the Whole Atmosphere Community Climate Model (WACCM) which is part of the Community Earth System Model version 1.0 (CESM1). WACCM is associated with the Community Aerosol and Radiation Model for Atmospheres (CARMA) sectional aerosol microphysics model which includes full sulphur chemical and microphysical cycles with no a priori assumption on particle size. Five main volcanic events (Kelud, Calbuco, Ambae, Raikoke and Ulawun) have been reported and are shown to have significantly influenced the stratospheric aerosol layer in the tropics, either through direct injection in this region or through transport from extra-tropical latitudes. Space-borne data as well as ground-based lidar and balloon-borne in situ observations are used to evaluate the model calculations in terms of aerosol content, vertical distribution, optical and microphysical properties, transport and residence time of the various volcanic plumes. Overall, zonal mean model results reproduce the occurrence and vertical extents of the plumes derived from satellite observations but shows some discrepancies for absolute values of extinction and of stratospheric aerosol optical depth (SAOD). Features of meridional transport of the plumes emitted from extra-tropical latitudes are captured by the model but simulated absolute values of SAOD differ from 6 to 200% among the various eruptions. Simulations tend to agree well with observed in situ vertical profiles for the Kelud and Calbuco plumes but this is likely to depend on the period for which comparison is done. Some explanations for the model–measurement discrepancies are discussed such as the inaccurate knowledge of the injection parameters and the presence of ash not accounted in the simulations.

Published
2022
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2. Two-year operation of the lidar 1200: from fine-scale tropospheric structures to lower stratospheric water vapor detection

Author

Françoise Posny, Franck Gabarrot, Guillaume Payen, Valentin Duflot, Jimmy Leclair de Bellevue, Holger Vömel, Nicolas Marquestaut, Philippe Keckhut, Jean-Marc Metzger, Hélène Vérèmes, Susanne Meier, Jean-Luc Baray, Jean-Pierre Cammas, Stephanie Evan, Ruud Dirksen, Observatoire des Sciences de l'Univers de La Réunion (OSU-Réunion), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR), Laboratoire de l'Atmosphère et des Cyclones (LACy), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire de Météorologie Physique (LaMP), Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Lindenberg Meteorological Observatory - Richard Assmann Observatory (MOL-RAO), Deutscher Wetterdienst [Offenbach] (DWD), Earth Observing Laboratory [Boulder] (EOL), National Center for Atmospheric Research [Boulder] (NCAR)-University Corporation for Atmospheric Research (UCAR), Observatoire des Sciences de l'Univers de La Réunion ( OSU-Réunion ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de la Réunion ( UR ), Laboratoire de l'Atmosphère et des Cyclones ( LACy ), Météo France-Université de la Réunion ( UR ) -Centre National de la Recherche Scientifique ( CNRS ), SHTI - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales ( LATMOS ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Météorologie Physique - Clermont Auvergne ( LaMP ), Institut national des sciences de l'Univers ( INSU - CNRS ) -Université Clermont Auvergne ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Lindenberg Meteorological Observatory - Richard Assmann Observatory ( MOL-RAO ), Deutscher Wetterdienst [Offenbach] ( DWD ), Earth Observing Laboratory [Boulder] ( EOL ), National Center for Atmospheric Research [Boulder] ( NCAR ) -University Corporation for Atmospheric Research ( UCAR ), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Time delay and integration, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 010504 meteorology & atmospheric sciences, Meteorology, Hygrometer, QC1-999, 0211 other engineering and technologies, 02 engineering and technology, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, Atmospheric sciences, 01 natural sciences, Troposphere, Lidar, [ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], 13. Climate action, Observatory, Scale (map), Stratosphere, Water vapor, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences
Abstract

International audience; The 2-year lidar water vapor database (November 2013 - October 2015) of the Maïdo Observatory (Reunion Island / 21°S,55.5°E) is now calibrated. The performance of the lidar to provide accurate vertical structures are shown to be good. The ability of measuring quantities of a few ppmv in the lower stratosphere is demonstrated up to 22 km (based on Cryogenic Frostpoint Hygrometer sondes/lidar profiles comparisons) for an integration time period of 48 hours and a vertical resolution of 1.3 km.

Published
2018
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3. A Raman lidar at Maïdo Observatory (Reunion Island) to measure water vapor in the troposphere and lower stratosphere: calibration and validation

Author

Susanne Meier, Guillaume Payen, Jean-Luc Baray, Stephanie Evan, Valentin Duflot, Françoise Posny, Jean-Pierre Cammas, Jimmy Leclair de Bellevue, Philippe Keckhut, Nicolas Marquestaut, Franck Gabarrot, Hélène Vérèmes, Ruud Dirksen, Holger Vömel, and Jean-Marc Metzger

Subjects
010504 meteorology & atmospheric sciences, Hygrometer, Meteorology, 010308 nuclear & particles physics, 01 natural sciences, law.invention, Troposphere, Altitude, Lidar, 13. Climate action, law, 0103 physical sciences, Radiosonde, Mixing ratio, Environmental science, 14. Life underwater, Stratosphere, Water vapor, 0105 earth and related environmental sciences, Remote sensing
Abstract

The Maïdo high-altitude observatory located in Reunion Island (21° S, 55.5° E) is equipped with Lidar1200, an innovative Raman lidar designed to measure the water vapor mixing ratio in the troposphere and the lower stratosphere. The calibration methodology is based on a GNSS (Global Navigation Satellite System) IWV (Integrated Water Vapor) dataset and lamp measurements. The mean relative standard error on the calibration coefficient is around 2.7 %. Two years of lidar water vapor measurements from November 2013 to October 2015 are now processed. By comparing CFH (Cryogenic Frost point Hygrometer) radiosonde profiles with the Raman lidar profiles, the ability of the lidar to provide accurate measurements is possible up to 22 km. The ability of measuring water vapor mixing ratios of a few ppmv in the lower stratosphere is demonstrated with a 48-hours integration time period, an absolute error lower than 0.8 ppmv and a relative error less than 20 %. This Raman lidar is dedicated to provide regular profiles of water vapor measurements with a high vertical resolution and low uncertainties to international networks; in the wider interest of research on stratosphere-troposphere exchange processes and on the long-term survey of water vapor in the upper troposphere and lower stratosphere in the Southern Hemisphere. A strategy of data sampling and filtering is proposed to meet these objectives with regard to the altitude range requested. 10-min time integration and 65–90 m vertical resolution ensure a vertical profile reaching 10 km, but more than 2800 minutes and a vertical resolution of 150–1300 m are necessary to reach the lower stratosphere with an uncertainty less than 20 %.

Published
2017
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4. Maïdo observatory: a new high-altitude station facility at Reunion Island (21° S, 55° E) for long-term atmospheric remote sensing and in situ measurements

Author

Françoise Posny, Yann Courcoux, F. Desmet, Karine Sellegri, Robert Delmas, M. De Mazière, Thierry Portafaix, Alain Hauchecorne, Jean Sciare, J. Leclair de Bellevue, Franck Gabarrot, S. Godin Beekmann, Guillaume Payen, Jean-Luc Baray, Aurélie Colomb, C. Vuillemin, Davide Dionisi, Valentin Duflot, Jacques Porteneuve, Jean-Pierre Cammas, T. Gaudo, Christelle Barthe, Philippe Ricaud, Pierre Tulet, Jean-Marc Metzger, Hélène Vérèmes, Abdel Abchiche, Michel Ramonet, Christian Hermans, Philippe Keckhut, Christophe Hoareau, Laboratoire de l'Atmosphère et des Cyclones (LACy), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Observatoire des Sciences de l'Univers de La Réunion (OSU-Réunion), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB), Laboratoire de météorologie physique (LaMP), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), ICOS-RAMCES (ICOS-RAMCES), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), 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), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Groupe d'étude de l'atmosphère météorologique (CNRM-GAME), and Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, lcsh:TA715-787, lcsh:Earthwork. Foundations, Climate change, Subtropics, 01 natural sciences, lcsh:Environmental engineering, 010309 optics, Troposphere, Lidar, Observatory, 0103 physical sciences, Environmental science, 14. Life underwater, lcsh:TA170-171, Sociologie politique, Southern Hemisphere, Stratosphere, Sea level, 0105 earth and related environmental sciences, Remote sensing
Abstract

Since the nineties, atmospheric measurement systems have been deployed at Reunion Island, mainly for monitoring the atmospheric composition in the framework of NDSC/NDACC (Network for the Detection of Stratospheric< /i> Change/Network for the Detection of Atmospheric Composition Change). The location of Reunion Island presents a great interest because there are very few multi-instrumented stations in the tropics and particularly in the southern hemisphere. In 2012, a new observatory was commissioned in Maïdo at 2200 m above sea level: it hosts various instruments for atmospheric measurements, including lidar systems, spectro-radiometers and in situ gas and aerosol measurements. This new high-altitude Maïdo station provides an opportunity: 1. to improve the performance of the optical instruments above the marine boundary layer, and to open new perspectives on upper troposphere and lower stratosphere studies; 2. to develop in situ measurements of the atmospheric composition for climate change surveys, in a reference site in the tropical/subtropical region of the southern hemisphere; 3. to offer trans-national access to host experiments or measurement campaigns for focused process studies. © 2013 Author(s)., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2013
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5. Ozone profiles by DIAL at Maïdo Observatory (Reunion Island) Part 1. Tropospheric ozone lidar: system description, performances evaluation and comparison with ancillary data

Author

Thierry Portafaix, Pierre-François Coheur, Martine De Mazière, Bavo Langerock, Guillaume Payen, Jean-Marc Metzger, Nicolas Marquestaut, Jean-Luc Baray, Valentin Duflot, Cathy Clerbaux, Françoise Posny, Jean-Pierre Cammas, Corinne Vigouroux, and Juliette Hadji-Lazaro

Subjects
010504 meteorology & atmospheric sciences, Meteorology, Infrared atmospheric sounding interferometer, Atmospheric sciences, 01 natural sciences, Dial, Troposphere, chemistry.chemical_compound, Altitude, Lidar, chemistry, Observatory, Environmental science, Tropospheric ozone, Stratosphere, 0105 earth and related environmental sciences
Abstract

Recognizing the importance of ozone in the troposphere and lower stratosphere in the tropics, a DIAL tropospheric ozone lidar system (LIO3TUR) was developped and installed at the Université de la Réunion campus site (close to the sea) in Reunion Island (southern tropics) in 1998. From 1998 to 2010, it acquired 427 ozone profiles from the low to the upper troposphere and has been central to several studies. In 2012, the system was moved up to the new Maïdo Observatory facility (2160 m above mean sea level – amsl) where it started operation in February 2013. The current system (LIO3T) configuration generates a 266 nm beam obtained with the fourth harmonic of a Nd:YAG laser sent into a Raman cell filled up with deuterium (using helium as buffer gas) generating the 289 and 316 nm beams enabling the use of the DIAL method for ozone profile measurements. Optimal range for the actual system is 6–19 km amsl, depending on the instrumental and atmospheric conditions; for a 1-hour integration time, vertical resolution varies from 0.7 km at 6 km amsl to 1.3 km at 19 km amsl, and mean uncertainty within the 6–19 km range is between 6 and 13 %. Comparisons with 8 electrochemical concentration cell (ECC) sondes simultaneously launched from the Maïdo Observatory show a good agreement between datasets with a 7.7 % mean absolute value of the relative differences with respect to the mean (D) between 6 and 17 km amsl (LIO3T low); comparisons with 37 ECC sondes launched from the nearby Gillot site during day time in a &pm;24-hour window around lidar shooting result in a 10.3 % D between 6 and 19 km amsl (LIO3T low); comparisons with 11 ground-based Network for Detection of Atmosphere Composition Change (NDACC) Fourier Transform Infrared (FTIR) spectrometer measurements acquired during day time in a &pm;24-hour window around lidar shooting show a good agreement between datasets with a D of 11.8 % for the 8.5–16 km partial column (LIO3T high); and comparisons with 39 simultaneous Infrared Atmospheric Sounding Interferometer (IASI) observations over Reunion Island show a good agreement between datasets with a D of 11.3 % for the 6–16 km partial column (LIO3T high). ECC, LIO3TUR and LIO3T O3 monthly climatologies all exhibit the same range of values and patterns. In particular, the southern hemisphere biomass burning seasonal enhancement, the ozonopause altitude decrease in late austral winter-spring, as well as the signature of deep convection bringing boundary layer-ozone poor air masses up to the mid-upper troposphere in late austral summer, are clearly visible on all datasets.

Published
2017
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7. Water vapor profiles up to the UT/LS from Raman lidar at Reunion Island (21°S, 55°E) : technical description, data processing and comparison with sondes

Author

Guillaume Payen, Valentin Duflot, Françoise Posny, Davide Dionisi, Franck Gabarrot, Jimmy Leclair de Bellevue, Stephanie Evan, Hélène Vérèmes, Jean-Pierre Cammas, Philippe Keckhut, Ruud Dirksen, Susanne Meier, Jean-Luc Baray, Holger Vömel, Laboratoire de l'Atmosphère et des Cyclones (LACy), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de La Réunion (OSU-Réunion), Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS), CNR Institute of Atmospheric Sciences and Climate (ISAC), Consiglio Nazionale delle Ricerche (CNR), Deutscher Wetterdienst [Offenbach] (DWD), National Center for Atmospheric Research [Boulder] (NCAR), European Community, Centre National de la Recherche Scientifique (CNRS), European Project: 262254,EC:FP7:INFRA,FP7-INFRASTRUCTURES-2010-1,ACTRIS(2011), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
010504 meteorology & atmospheric sciences, Meteorology, QC1-999, 0211 other engineering and technologies, 02 engineering and technology, 01 natural sciences, law.invention, Troposphere, symbols.namesake, law, Mixing ratio, Calibration, Rayleigh scattering, Stratosphere, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, Physics, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Lidar, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, symbols, Radiosonde, Water vapor
Abstract

International audience; The Maïdo high-altitude observatory located in Reunion Island (21°S, 55°E) is equipped with an innovative lidar designed to monitor the water vapor in the whole troposphere up to the lower stratosphere with a Raman system and to monitor, simultaneously, the temperature in the stratosphere and in the mesosphere based on a Rayleigh scattering technique. Several improvements have been performed on the new instrument to optimize the water vapor mixing ratio measurements thanks to the experience of the previous system. The choice of the operational configuration of the system and the calibration methodology were realized during the campaign MALICCA-1 (MAïdo LIdar Calibration CAmpaign) which provided simultaneous measurements of water vapor and ozone in April 2013. The lidar water vapor profiles are calibrated with water vapor columns obtained from a collocated GNSS receiver. By comparing CFH and Vaisala radiosondes and satellites water vapor mixing ratio profiles with the Raman lidar profiles, the performances of the lidar are shown to be good in the troposphere. With a suitable integration time period, the ability of measuring quantities of a few ppmv in the lower stratosphere is demonstrated. This Raman lidar will provide regular measurements to international networks with high vertical resolution profiles of water vapor in order to document various studies and to insure a long-term survey of the troposphere and of the lower stratosphere.

Published
2015
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8. Introduction to the Maïdo Lidar Calibration Campaign dedicated to the validation of upper air meteorological parameters

Author

Brigitte Tschanz, Françoise Posny, Rolf Rüfenacht, Guillaume Payen, Abdel Abchiche, Valentin Duflot, Sergey Khaykin, Franck Gabarrot, Alain Hauchecorne, Niklaus Kämpfer, Jimmy Leclair-de-Bellevue, Philippe Keckhut, Hélène Vérèmes, Jacques Porteneuve, Davide Dionisi, Philippe Ricaud, Jean-Luc Baray, Stephanie Evan, Yann Courcoux, Jean-Pierre Cammas, STRATO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de La Réunion (OSU-Réunion), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR), Laboratoire de météorologie physique (LaMP), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Atmosphère et des Cyclones (LACy), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Institute of Applied Physics [Bern] (IAP), University of Bern, 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), Division technique INSU/SDU (DTI), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Météo France, Groupe d'étude de l'atmosphère météorologique (CNRM-GAME), and Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], 010504 meteorology & atmospheric sciences, Meteorology, Observatories, Water, 010501 environmental sciences, 01 natural sciences, Atmosphere, LIDAR, Lidar, 13. Climate action, Observatory, Mesopause, Calibration, General Earth and Planetary Sciences, Environmental science, Cirrus, Satellite, Stratosphere, Water vapor, 0105 earth and related environmental sciences, Remote sensing
Abstract

International audience; The first operations at the new High-altitude Maïdo Observatory at La Réunion began in 2013. The Maïdo Lidar Calibration Campaign (MALICCA) was organized there in April 2013 and has focused on the validation of the thermodynamic parameters (temperature, water vapor, and wind) measured with many instruments including the new very large lidar for water vapor and temperature profiles. The aim of this publication consists of providing an overview of the different instruments deployed during this campaign and their status, some of the targeted scientific questions and associated instrumental issues. Some specific detailed studies for some individual techniques were addressed elsewhere. This study shows that temperature profiles were obtained from the ground to the mesopause (80 km) thanks to the lidar and regular meteorological balloon-borne sondes with an overlap range showing good agreement. Water vapor is also monitored from the ground to the mesopause by using the Raman lidar and microwave techniques. Both techniques need to be pushed to their limit to reduce the missing range in the lower stratosphere. Total columns obtained from global positioning system or spectrometers are valuable for checking the calibration and ensuring vertical continuity. The lidar can also provide the vertical cloud structure that is a valuable complementary piece of information when investigating the water vapor cycle. Finally, wind vertical profiles, which were obtained from sondes, are now also retrieved at Maïdo from the newly implemented microwave technique and the lidar. Stable calibrations as well as a small-scale dynamical structure are required to monitor the thermodynamic state of the middle atmosphere, ensure validation of satellite sensors, study the transport of water vapor in the vicinity of the tropical tropopause and study their link with cirrus clouds and cyclones and the impact of small-scale dynamics (gravity waves) and their link with the mean state of the mesosphere.

Published
2015
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9. Marine and biomass burning aerosols in the southern Indian Ocean: Retrieval of aerosol optical properties from shipborne lidar and Sun photometer measurements

Author

Patrick Chazette, Robert Delmas, Valentin Duflot, Yann Courcoux, Jean-Luc Baray, Philippe Royer, Laboratoire de l'Atmosphère et des Cyclones (LACy), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), LEOSPHERE France, LEOSPHERE, Chimie Atmosphérique Expérimentale (CAE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Équipe Troposphère, Laboratoire de l'Atmosphère et des Cyclones ( LACy ), Météo France-Université de la Réunion ( UR ) -Centre National de la Recherche Scientifique ( CNRS ) -Météo France-Université de la Réunion ( UR ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] ( LSCE ), and Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS )

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, aerosol, Soil Science, sun photometer, Aquatic Science, Oceanography, Atmospheric sciences, 01 natural sciences, 010309 optics, Sun photometer, Geochemistry and Petrology, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Calibration, 14. Life underwater, Southern Hemisphere, Indian Ocean, Sea level, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Lidar, Ecology, Troposphere: constituent transport and chemistry, Paleontology, Instruments and techniques, Forestry, Plume, Aerosol, Indian ocean, Geophysics, 0305 Aerosols and particles, [ PHYS.PHYS.PHYS-AO-PH ] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], 13. Climate action, Space and Planetary Science, Environmental science
Abstract

We document aerosol extinction properties in the southern Indian Ocean. A unique data set of shipborne measurements has been collected with a dual Rayleigh-Mie lidar aboard the research vessel Marion Dufresne during two campaigns: one around Madagascar during the Southern Hemisphere late summer and one close to the Kerguelen Islands during the biomass burning (BB) season. During this latter, a layer containing a mix of BB and marine aerosols extending up to similar to 3 km above mean sea level (amsl) has been observed from [31 degrees S, 69 degrees E] to [24 degrees S, 59 degrees E]. Both vertical structure and aerosol optical properties have been retrieved from the inversion of the lidar signals. Sun photometer-derived aerosol optical thickness (AOT) at 355 nm is used to constrain the lidar inversion. We obtain a mean integrated value of backscatter-to-extinction ratio (BER) (extinction-to-backscatter ratio, or so-called lidar ratio, LR) of 0.039 +/- 0.009 sr(-1) (26 +/- 6 sr) and 0.021 +/- 0.006 sr(-1) (48 +/- 12 sr) for the marine aerosols layer, and for the mixing between BB and marine aerosols with an uncertainty of 0.009 sr-1 (6 sr) and 0.004 sr(-1) (9 sr), respectively. Lidar calibration is used to inverse data without any simultaneous Sun photometer measurements (as nighttime data), and the temporal evolution of the optical properties and vertical extension of the BB aerosol plume is documented. The presence of BB aerosols is in agreement with Lagrangian model GIRAFE v3 (reGIonal ReAl time Fire plumEs) simulations, which show the South American and Southern African BB origin of the encountered aerosol layer.

Published
2011
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10. Tropical Forests of Réunion Island Classified from Airborne Full-Waveform LiDAR Measurements

Author

Julien Totems, Jacques Fournel, Valentin Duflot, Pierre Tulet, Elsa Dieudonné, Eric Hamonou, Olivier Flores, Patrick Chazette, Dominique Strasberg, Xiaoxia Shang, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie Atmosphérique Expérimentale (CAE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire de l'Atmosphère et des Cyclones (LACy), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Peuplements végétaux et bioagresseurs en milieu tropical (UMR PVBMT), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université de La Réunion (UR), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université de La Réunion (UR)-Institut National de la Recherche Agronomique (INRA), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
tropical forest, Canopy, canopy height, 010504 meteorology & atmospheric sciences, Science, Biome, 0211 other engineering and technologies, 02 engineering and technology, Rainforest, Atmospheric sciences, 01 natural sciences, Leaf area index, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Cloud forest, geography, airborne LiDAR, Leaf Area Index, apparent foliage, Plateau, geography.geographical_feature_category, 15. Life on land, Tropical forest, Lidar, General Earth and Planetary Sciences, Environmental science
Abstract

International audience; From an unprecedented experiment using airborne measurements performed over the rich forests of Réunion Island, this paper aims to present a methodology for the classification of diverse tropical forest biomes as retrieved from vertical profiles measured using a full-waveform LiDAR. This objective is met through the retrieval of both the canopy height and the Leaf Area Index (LAI), obtained as an integral of the foliage profile. The campaign involved sites ranging from coastal to rain forest, including tropical montane cloud forest, as found on the Bélouve plateau. The mean values of estimated LAI retrieved from the apparent foliage profile are between ~5 and 8 m 2 /m 2 , and the mean canopy height values are ~15 m for both tropical montane cloud and rain forests. Good agreement is found between LiDAR-and MODIS-derived LAI for moderate LAI (~5 m 2 /m 2), but the LAI retrieved from LiDAR is larger than MODIS on thick rain forest sites (~8 against ~6 m 2 /m 2 from MODIS). Regarding the characterization of tropical forest biomes, we show that the rain and montane tropical forests can be well distinguished from planted forests by the use of the parameters directly retrieved from LiDAR measurements.

Published
2016
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