Search

Your search keyword '"Baray, Jean-Luc"' showing total 170 results
Start Over Author "Baray, Jean-Luc" Publication Year Range Last 10 years
170 results on '"Baray, Jean-Luc"'

5. VELVET: an enclosure vegetation system to measure BVOC emission fingerprints in temperate and tropical climates

Author

Rocco, Manon, primary, Brugere, Etienne, additional, Magand, Olivier, additional, Borbon, Agnes, additional, Colomb, Aurelie, additional, Bouvier, Laetitia, additional, Baray, Jean-Luc, additional, Duflot, Valentin, additional, Ribeiro, Mickael, additional, Picard, David, additional, Metzger, Jean-Marc, additional, Stamenoff, Pierre, additional, Benoit, Yoan, additional, and Ah-Peng, Claudine, additional

Published
2024
Full Text
View/download PDF

6. Temporal variations of antimicrobial resistance genes in aerosols: A one-year monitoring at the puy de Dôme summit (Central France)

Author

Rossi, Florent, primary, Duchaine, Caroline, additional, Tignat-Perrier, Romie, additional, Joly, Muriel, additional, Larose, Catherine, additional, Dommergue, Aurélien, additional, Turgeon, Nathalie, additional, Veillette, Marc, additional, Sellegri, Karine, additional, Baray, Jean-Luc, additional, and Amato, Pierre, additional

Published
2023
Full Text
View/download PDF

7. Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)

Author

Salignat, Romain, Rissanen, Matti, Iyer, Siddharth, Baray, Jean-Luc, Tulet, Pierre, Metzger, Jean-Marc, Brioude, Jérôme, Sellegri, Karine, and Rose, Clémence

Subjects
MOLECULAR clusters, ATMOSPHERIC ammonia, CLOUD condensation nuclei, TIME-of-flight mass spectrometers, ATMOSPHERIC ionization, SULFUR cycle, TROPOSPHERE
Abstract

New particle formation (NPF) in the free troposphere (FT) is thought to be a significant source of particles over the oceans. The entrainment of particles initially formed in the marine FT is further suspected to be a major contributor to cloud condensation nuclei (CCN) number concentrations in the marine boundary layer (BL). Yet, little is known about the process and, more broadly, about the composition of the marine FT, which remains poorly explored due to access difficulties. Here we report measurements performed in April 2018 at the Maïdo Observatory with a nitrate-based chemical ionization atmospheric pressure interface time-of-flight mass spectrometer, which have allowed the first molecular-level characterization of the remote marine FT composition. A number of molecules and clusters were identified and classified into nine groups according to their chemical composition; among the identified species, the groups containing methanesulfonic acid (MSA) and C2 amines show signals that are on average significantly higher when the site is under conditions representative of the marine FT (compared to the BL). The correlation analysis revealed apparent connections between the signals of the identified compounds and several variables concurrently measured at the site (under FT conditions) or related to air mass history, suggesting that oxalic acid, malonic acid, and observed C2 amines could be of terrestrial origin, with, in addition, a possible marine source for oxalic acid and amines, while iodic acid, sulfur species, and maleic acid have a dominant marine origin. Identification of FT conditions at the site was based on the analysis of the standard deviation of the wind direction; this parameter, which can easily be derived from continuous measurements at the site, is shown in the first part of the study to be a relevant tracer when compared to predictions from the Meso-NH atmospheric model. Similar to other high-altitude sites, FT conditions are mainly encountered at night at Maïdo; therefore, the link to NPF could not be established, and further research is needed to assess the composition of precursors to nanoparticle formation in the marine FT. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

12. Measurement Report: Bio-physicochemistry of tropical clouds at Maïdo (Réunion Island, Indian Ocean): overview of results from the BIO-MAÏDO campaign

Author

Leriche, Maud, primary, Tulet, Pierre, additional, Deguillaume, Laurent, additional, Burnet, Frédéric, additional, Colomb, Aurélie, additional, Borbon, Agnès, additional, Jambert, Corinne, additional, Duflot, Valentin, additional, Houdier, Stéphan, additional, Jaffrezo, Jean-Luc, additional, Vaïtilingom, Mickaël, additional, Dominutti, Pamela, additional, Rocco, Manon, additional, Mouchel-Vallon, Camille, additional, El Gdachi, Samira, additional, Brissy, Maxence, additional, Fathalli, Maroua, additional, Maury, Nicolas, additional, Verreyken, Bert, additional, Amelynck, Crist, additional, Schoon, Niels, additional, Gros, Valérie, additional, Pichon, Jean-Marc, additional, Ribeiro, Mickael, additional, Pique, Eric, additional, Leclerc, Emmanuel, additional, Bourrianne, Thierry, additional, Roy, Axel, additional, Moulin, Eric, additional, Barrie, Joël, additional, Metzger, Jean-Marc, additional, Péris, Guillaume, additional, Guadagno, Christian, additional, Bhugwant, Chatrapatty, additional, Tibere, Jean-Mathieu, additional, Tournigand, Arnaud, additional, Freney, Evelyn, additional, Sellegri, Karine, additional, Delort, Anne-Marie, additional, Amato, Pierre, additional, Joly, Muriel, additional, Baray, Jean-Luc, additional, Renard, Pascal, additional, Bianco, Angelica, additional, Réchou, Anne, additional, and Payen, Guillaume, additional

Published
2023
Full Text
View/download PDF

13. Supplementary material to "Measurement Report: Bio-physicochemistry of tropical clouds at Maïdo (Réunion Island, Indian Ocean): overview of results from the BIO-MAÏDO campaign"

Author

Leriche, Maud, primary, Tulet, Pierre, additional, Deguillaume, Laurent, additional, Burnet, Frédéric, additional, Colomb, Aurélie, additional, Borbon, Agnès, additional, Jambert, Corinne, additional, Duflot, Valentin, additional, Houdier, Stéphan, additional, Jaffrezo, Jean-Luc, additional, Vaïtilingom, Mickaël, additional, Dominutti, Pamela, additional, Rocco, Manon, additional, Mouchel-Vallon, Camille, additional, El Gdachi, Samira, additional, Brissy, Maxence, additional, Fathalli, Maroua, additional, Maury, Nicolas, additional, Verreyken, Bert, additional, Amelynck, Crist, additional, Schoon, Niels, additional, Gros, Valérie, additional, Pichon, Jean-Marc, additional, Ribeiro, Mickael, additional, Pique, Eric, additional, Leclerc, Emmanuel, additional, Bourrianne, Thierry, additional, Roy, Axel, additional, Moulin, Eric, additional, Barrie, Joël, additional, Metzger, Jean-Marc, additional, Péris, Guillaume, additional, Guadagno, Christian, additional, Bhugwant, Chatrapatty, additional, Tibere, Jean-Mathieu, additional, Tournigand, Arnaud, additional, Freney, Evelyn, additional, Sellegri, Karine, additional, Delort, Anne-Marie, additional, Amato, Pierre, additional, Joly, Muriel, additional, Baray, Jean-Luc, additional, Renard, Pascal, additional, Bianco, Angelica, additional, Réchou, Anne, additional, and Payen, Guillaume, additional

Published
2023
Full Text
View/download PDF

14. Supplementary material to "Measurement Report: Insights into the chemical composition of molecular clusters present in the free troposphere over the Southern Indian Ocean: observations from the Maïdo observatory (2150 m a.s.l., Reunion Island)"

Author

Salignat, Romain, primary, Rissanen, Matti, additional, Iyer, Siddharth, additional, Baray, Jean-Luc, additional, Tulet, Pierre, additional, Metzger, Jean-Marc, additional, Brioude, Jérôme, additional, Sellegri, Karine, additional, and Rose, Clémence, additional

Published
2023
Full Text
View/download PDF

15. Measurement Report: Insights into the chemical composition of molecular clusters present in the free troposphere over the Southern Indian Ocean: observations from the Maïdo observatory (2150 m a.s.l., Reunion Island)

Author

Salignat, Romain, primary, Rissanen, Matti, additional, Iyer, Siddharth, additional, Baray, Jean-Luc, additional, Tulet, Pierre, additional, Metzger, Jean-Marc, additional, Brioude, Jérôme, additional, Sellegri, Karine, additional, and Rose, Clémence, additional

Published
2023
Full Text
View/download PDF

16. Sea2Cloud: From Biogenic Emission Fluxes to Cloud Properties in the Southwest Pacific

Author

Sellegri, Karine, primary, Harvey, Mike, additional, Peltola, Maija, additional, Saint-Macary, Alexia, additional, Barthelmeß, Theresa, additional, Rocco, Manon, additional, Moore, Kathryn A., additional, Cristi, Antonia, additional, Peyrin, Frederic, additional, Barr, Neill, additional, Labonnote, Laurent, additional, Marriner, Andrew, additional, McGregor, John, additional, Safi, Karl, additional, Deppeler, Stacy, additional, Archer, Stephen, additional, Dunne, Erin, additional, Harnwell, James, additional, Delanoe, Julien, additional, Freney, Evelyn, additional, Rose, Clémence, additional, Bazantay, Clément, additional, Planche, Céline, additional, Saiz-Lopez, Alfonso, additional, Quintanilla-López, Jesús E., additional, Lebrón-Aguilar, Rosa, additional, Rinaldi, Matteo, additional, Banson, Sandra, additional, Joseph, Romain, additional, Lupascu, Aurelia, additional, Jourdan, Olivier, additional, Mioche, Guillaume, additional, Colomb, Aurélie, additional, Olivares, Gus, additional, Querel, Richard, additional, McDonald, Adrian, additional, Plank, Graeme, additional, Bukosa, Beata, additional, Dillon, Wayne, additional, Pelon, Jacques, additional, Baray, Jean-Luc, additional, Tridon, Frederic, additional, Donnadieu, Franck, additional, Szczap, Frédéric, additional, Engel, Anja, additional, DeMott, Paul J., additional, and Law, Cliff S., additional

Published
2023
Full Text
View/download PDF

20. Sea2Cloud: From Biogenic Emission Fluxes to Cloud Properties in the Southwest Pacific

Author

Sellegri, Karine, Harvey, Mike, Peltola, Maija, Saint-Macary, Alexia, Barthelmess, Theresa, Rocco, Manon, Moore, Kathryn A., Cristi, Antonia, Peyrin, Frederic, Barr, Neill, Labonnote, Laurent, Marriner, Andrew, McGregor, John, Safi, Karl, Deppeler, Stacy, Archer, Stephen, Dunne, Erin, Harnwell, James, Delanoe, Julien, Freney, Evelyn, Rose, Clémence, Bazantay, Clément, Planche, Céline, Saiz-Lopez, Alfonso, Quintanilla-López, Jesús E., Lebrón-Aguilar, Rosa, Rinaldi, Matteo, Banson, Sandra, Joseph, Romain, Lupascu, Aurelia, Jourdan, Olivier, Mioche, Guillaume, Colomb, Aurélie, Olivares, Gus, Querel, Richard, McDonald, Adrian, Plank, Graeme, Bukosa, Beata, Dillon, Wayne, Pelon, Jacques, Baray, Jean-Luc, Tridon, Frederic, Donnadieu, Franck, Szczap, Frédéric, Engel, Anja, DeMott, Paul J., Law, Cliff S., Sellegri, Karine, Harvey, Mike, Peltola, Maija, Saint-Macary, Alexia, Barthelmess, Theresa, Rocco, Manon, Moore, Kathryn A., Cristi, Antonia, Peyrin, Frederic, Barr, Neill, Labonnote, Laurent, Marriner, Andrew, McGregor, John, Safi, Karl, Deppeler, Stacy, Archer, Stephen, Dunne, Erin, Harnwell, James, Delanoe, Julien, Freney, Evelyn, Rose, Clémence, Bazantay, Clément, Planche, Céline, Saiz-Lopez, Alfonso, Quintanilla-López, Jesús E., Lebrón-Aguilar, Rosa, Rinaldi, Matteo, Banson, Sandra, Joseph, Romain, Lupascu, Aurelia, Jourdan, Olivier, Mioche, Guillaume, Colomb, Aurélie, Olivares, Gus, Querel, Richard, McDonald, Adrian, Plank, Graeme, Bukosa, Beata, Dillon, Wayne, Pelon, Jacques, Baray, Jean-Luc, Tridon, Frederic, Donnadieu, Franck, Szczap, Frédéric, Engel, Anja, DeMott, Paul J., and Law, Cliff S.

Abstract

The goal of the Sea2Cloud project is to study the interplay between surface ocean biogeochemical and physical properties, fluxes to the atmosphere, and ultimately their impact on cloud formation under minimal direct anthropogenic influence. Here we present an interdisciplinary approach, combining atmospheric physics and chemistry with marine biogeochemistry, during a voyage between 41 degrees and 47 degrees S in March 2020. In parallel to ambient measurements of atmospheric composition and seawater biogeochemical properties, we describe semicontrolled experiments to characterize nascent sea spray properties and nucleation from gas-phase biogenic emissions. The experimental framework for studying the impact of the predicted evolution of ozone concentration in the Southern Hemisphere is also detailed. After describing the experimental strategy, we present the oceanic and meteorological context including provisional results on atmospheric thermodynamics, composition, and flux measurements. In situ measurements and flux studies were carried out on different biological communities by sampling surface seawater from subantarctic, subtropical, and frontal water masses. Air-Sea-Interface Tanks (ASIT) were used to quantify biogenic emissions of trace gases under realistic environmental conditions, with nucleation observed in association with biogenic seawater emissions. Sea spray continuously generated produced sea spray fluxes of 34% of organic matter by mass, of which 4% particles had fluorescent properties, and which size distribution resembled the one found in clean sectors of the Southern Ocean. The goal of Sea2Cloud is to generate realistic parameterizations of emission flux dependences of trace gases and nucleation precursors, sea spray, cloud condensation nuclei, and ice nuclei using seawater biogeochemistry, for implementation in regional atmospheric models.

Published
2023
Full Text
View/download PDF

21. Chemical and biological signatures of water and fluxes from clouds to rivers at the watershed level in a natural context.

Author

Labed-Veydert, Tiphaine, primary, Joly, Muriel, additional, Judon, Céline, additional, Leremboure, Martin, additional, Voyard, Guillaume, additional, Forano, Claude, additional, Bianco, Angélica, additional, Baray, Jean-Luc, additional, Artigas, Joan, additional, Mallet, Clarisse, additional, Latour, Delphine, additional, Roussel, Erwan, additional, Jame, Patrick, additional, Bonjour, Erik, additional, Jabot, Franck, additional, Pottier, Julien, additional, and Amato, Pierre, additional

Published
2023
Full Text
View/download PDF

24. Seasonal Variations of Antimicrobial Resistance Genes in Aerosols: A One-Year Monitoring at the Puy De Dôme Summit (Central France)

Author

Rossi, Florent, primary, Duchaine, Caroline, additional, Tignat-Perrier, Romie, additional, Joly, Muriel, additional, Larose, Catherine, additional, Dommergue, Aurelien, additional, Turgeon, Nathalie, additional, Veillette, Marc, additional, Sellegri, Karine, additional, Baray, Jean-Luc, additional, and Amato, Pierre, additional

Published
2023
Full Text
View/download PDF

26. Sea2Cloud: from biogenic emission fluxes to cloud properties in the South West Pacific

Author

Sellegri, Karine, Harvey, Mike, Peltola, Maija, Saint-Macary, Alexia, Barthelmeß, Theresa, Rocco, Manon, Moore, Kathryn, Cristi, Antonia, Peyrin, Frederic, Barr, Neill, Labonnote, Laurent, Marriner, Andrew, Mcgregor, John, Safi, Karl, Deppeler, Stacy, Archer, Stephen, Dunne, Erin, Harnwell, James, Delanoë, Julien, Freney, Evelyn, Rose, Clémence, Bazantay, Clément, Planche, Céline, Saiz-Lopez, Alfonso, Quintanilla-López, Jesús, Lebrón-Aguilar, Rosa, Rinaldi, Matteo, Banson, Sandra, Joseph, Romain, Lupascu, Aurelia, Jourdan, Olivier, Mioche, Guillaume, Colomb, Aurélie, Olivares, Gus, Querel, Richard, Mcdonald, Adrian, Plank, Graeme, Bukosa, Beata, Dillon, Wayne, Pelon, Jacques, Picard, David, Baray, Jean-Luc, Tridon, Frederic, Donnadieu, Franck, Szczap, Frédéric, Engel, Anja, Demott, Paul, Law, Cliff, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), National Institute of Water and Atmospheric Research [Wellington] (NIWA), Department of Marine Sciences [Dunedin], University of Otago [Dunedin, Nouvelle-Zélande], Helmholtz Centre for Ocean Research [Kiel] (GEOMAR), Department of Atmospheric Science [Fort Collins], Colorado State University [Fort Collins] (CSU), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), National Institute of Water and Atmosphere [Hamilton] (NIWA), University of Auckland [Auckland], CSIRO Marine and Atmospheric Research [Aspendale], Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), SPACE - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), 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), Instituto de Química Física Rocasolano (IQFR), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Istituto di Scienze dell'Atmosfera e del Clima [Bologna] (ISAC), Consiglio Nazionale delle Ricerche (CNR), Institute for Advanced Sustainability Studies [Potsdam] (IASS), National Institute of Water and Atmospheric Research [Auckland] (NIWA), National Institute of Water and Atmospheric Research [Lauder] (NIWA), University of Canterbury [Christchurch], Department of Chemistry [Dunedin], 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 National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)

Subjects
Atmospheric Science, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology
Abstract

The goal of the Sea2Cloud project is to study the interplay between surface ocean biogeochemical and physical properties, fluxes to the atmosphere, and ultimately their impact on cloud formation under minimal direct anthropogenic influence. Here we present an interdisciplinary approach, combining atmospheric physics and chemistry with marine biogeochemistry, during a voyage between 41° and 47°S in March 2020. In parallel to ambient measurements of atmospheric composition and seawater biogeochemical properties, we describe semicontrolled experiments to characterize nascent sea spray properties and nucleation from gas-phase biogenic emissions. The experimental framework for studying the impact of the predicted evolution of ozone concentration in the Southern Hemisphere is also detailed. After describing the experimental strategy, we present the oceanic and meteorological context including provisional results on atmospheric thermodynamics, composition, and flux measurements. In situ measurements and flux studies were carried out on different biological communities by sampling surface seawater from subantarctic, subtropical, and frontal water masses. Air–Sea-Interface Tanks (ASIT) were used to quantify biogenic emissions of trace gases under realistic environmental conditions, with nucleation observed in association with biogenic seawater emissions. Sea spray continuously generated produced sea spray fluxes of 34% of organic matter by mass, of which 4% particles had fluorescent properties, and which size distribution resembled the one found in clean sectors of the Southern Ocean. The goal of Sea2Cloud is to generate realistic parameterizations of emission flux dependences of trace gases and nucleation precursors, sea spray, cloud condensation nuclei, and ice nuclei using seawater biogeochemistry, for implementation in regional atmospheric models.

Published
2023

27. Impacts of thermodynamics and aerosol particles on Arctic mixed-phase cloud microphysics over different surface conditions

Author

Arteaga, Diana, Wobrock, Wolfram, Banson, Sandra, Dupuy, Régis, Mioche, Guillaume, Tridon, Frédéric, Baray, Jean-Luc, Jourdan, Olivier, and Planche, Celine

Abstract

Different physical processes associated with surface and thermodynamical conditions as well as aerosol concentrations influence the formation and persistence of mixed-phase clouds (MPCs) in the Arctic. This study focuses on the impact of thermodynamical conditions and aerosol concentrations (cloud condensation nuclei (CCN) and ice-nucleating particles (INP)) on cloud microphysical properties. Two Arctic mixed-phase cloud systems measured the 17 June 2017 during the ACLOUD airborne campaign are simulated with the WRF model. In situ microphysical observations of cloud number and mass concentrations performed by aircraft microphysics probes are compared to WRF outputs. To investigate the effect of changing surfaces, two types of scenarios were studied: over sea ice and over open ocean. The MPC over open ocean is characterized by a higher liquid water content (LWC) and a lower ice water content (IWC) compared to the MPC over sea ice. Two microphysics schemes were tested: the two-moment schemes of Morrison and Milbrandt. Sensitivity studies have been carried out to investigate the impact of the thermodynamics, the surface properties and the aerosol loading on the LWC and the IWC. The first sensitivity test shows the large impact of the thermodynamics on the cloud properties since using the ERA5 reanalysis data with different vertical levels for initialization impact the simulated LWC and IWC profiles. Additional studies have been performed highlighting the important role of the CCN and INP on the formation and properties of the studied MPCs., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

28. Bio-physicochemistry of tropical clouds at Maïdo (Réunion Island, Indian Ocean): overview of results from the BIO-MAÏDO campaign

Author

Leriche, Maud, Tulet, Pierre, Deguillaume, Laurent, Burnet, Frédéric, Colomb, Aurélie, Borbon, Agnès, Jambert, Corinne, Duflot, Valentin, Houdier, Stéphan, Jaffrezo, Jean-Luc, Vaïtilingom, Mickaël, Mouchel-Vallon, Camille, Dominutti, Pamela, Rocco, Manon, Gdachi, Samira, Brissy, Maxence, Fathalli, Maroua, Maury, Nicolas, Verreyken, Bert, Amelynck, Crist, Schoon, Niels, Gros, Valérie, Pichon, Jean-Marc, Ribeiro, Mickael, Pique, Eric, Leclerc, Emmanuel, Bourrianne, Thierry, Roy, Axel, Moulin, Eric, Barrie, Joël, Metzger, Jean-Marc, Péris, Guillaume, Guadagno, Christian, Bhugwant, Chatrapatty, Tibere, Jean-Mathieu, Tournigand, Arnaud, Freney, Evelyn, Sellegri, Karine, Delort, Anne-Marie, Amato, Pierre, Joly, Muriel, Baray, Jean-Luc, Renard, Pascal, Bianco, Angelica, Réchou, Anne, Payen, Guillaume, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Centre ESCER, Université du Québec à Montréal = University of Québec in Montréal (UQAM), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-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)-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), Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre national de recherches météorologiques (CNRM), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), 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), 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, Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Laboratoire de Recherche en Géosciences et Energies [UR2_1] (LARGE), Université des Antilles (UA), Institut de Chimie de Clermont-Ferrand (ICCF), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national polytechnique Clermont Auvergne (INP Clermont Auvergne), Université Clermont Auvergne (UCA)-Université Clermont Auvergne (UCA), Department of Chemistry, University of Ghent, Ghent, Belgium, Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Departement of Chemistry, University of Ghent, 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), 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), ATMO-Réunion, ANR, BIO-MAÏDO, OCTAVE, European Project: 654109,H2020,H2020-INFRAIA-2014-2015,ACTRIS-2(2015), and ANR-18-CE01-0013,BIO-MAIDO,Bio-physicochimie des nuages tropicaux au Maïdo (Île de la Réunion) : processus et impacts sur la formation des aérosols organiques secondaires(2018)

Subjects
Atmospheric chemistry, Field campaign, tropical atmosphere, [SDU]Sciences of the Universe [physics], COV, Réunion Island, cloud, aerosols
Abstract

The BIO-MAÏDO (Bio-physicochemistry of tropical clouds at Maïdo (Réunion Island): processes and impacts on secondary organic aerosols formation) campaign was conducted from the 13th of March to the 4th of April 2019 on the tropical Réunion Island and implied several scientific teams and state-of-the-art instrumentation. The campaign was part of the BIO-MAÏDO project with the main objective is to improve our understanding of cloud impacts on the formation of secondary organic aerosols (SOA) from biogenic volatile organic compounds (BVOC) precursors in a tropical environment. Instruments were deployed at five sites: a receptor site, the Maïdo observatory (MO) at 2165 m asl, and four sites along the slope of the Maïdo mountain. The obtained dataset includes measurements of the gas-phase mixings ratio of volatile organic compounds (VOC), the characterization of the physical, chemical, and biological (bacterial diversity) properties of aerosols and the characterization of the physical, chemical and biological (identification of viable bacteria through culture-based approaches) properties of the cloud water. In addition, the turbulent parameters of the boundary layer, radiative fluxes, and emissions fluxes of BVOC from the surrounding vegetation were measured to help with the interpretation of the observed chemical concentrations in the different phases. Dynamical analyses using back-trajectories show two preferred trajectories routes for air masses arriving at MO during the daytime both corresponding to the return branches of the trade winds associated with the up-slopes thermal breezes, and both influenced by marine boundary layer and endemic forest below the Maïdo observatory. Additional analysis based on a high-resolution Meso-NH simulation for a typical cloudy day indicates that air masses sampled at MO likely encountered cloud processing during its transport along the slope. The highest mixing ratio of oxygenated VOC (OVOC) were measured above the site located in the endemic forest and the highest contribution of OVOC to total VOC at MO. Chemical composition of particles during the daytime shows that organic aerosol is more oxidized at MO than at other sites along the slope. This is a signature of photochemical aerosols aging along the slope. A higher concentration of oxalic acid at a site below MO indicates this oxidation occurs potentially through cloud processing. Despite an in-depth analysis of organic compounds in cloud water, around 80% on average of dissolved organic compounds is undefined highlighting the complexity of the cloud organic matter. The BIO-MAÏDO project is focusing on the analysis of observations and processes using numerical simulations: a 0D cloud chemistry model including biodegradation by bacteria in cloud water and a high-resolution 3D model coupling dynamical, microphysical and chemical processes.

Published
2023

29. Evaluation of the Sources, Precursors, and Processing of Aerosols at a High-Altitude Tropical Site

Author

Dominutti, Pamela, Chevassus, Emmanuel, Baray, Jean-Luc, Jaffrezo, Jean-Luc, Borbon, Agnès, Colomb, Aurélie, Deguillaume, Laurent, El Gdachi, Samira, Houdier, Stephan, Leriche, Maud, Metzger, Jean-Marc, Rocco, Manon, Tulet, Pierre, Sellegri, Karine, Freney, Evelyn, Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-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)-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), 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, Centre ESCER, Université du Québec à Montréal = University of Québec in Montréal (UQAM), 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), ANR-18-CE01-0013,BIO-MAIDO,Bio-physicochimie des nuages tropicaux au Maïdo (Île de la Réunion) : processus et impacts sur la formation des aérosols organiques secondaires(2018), and European Project: 654109,H2020,H2020-INFRAIA-2014-2015,ACTRIS-2(2015)

Subjects
Atmospheric Science, Cloud processing, Positive matrix factorization, Space and Planetary Science, Geochemistry and Petrology, ToF-ACSM, [SDE.IE]Environmental Sciences/Environmental Engineering, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, [SDE.MCG]Environmental Sciences/Global Changes, Secondary organic aerosols, Aqueous-phase chemistry, Southern Hemisphere, [SDE.ES]Environmental Sciences/Environmental and Society
Abstract

International audience; This work presents the results from a set of aerosol- and gas-phase measurements collected during the BIO-MAIDÖ field campaign in Reunion ́ between March 8 and April 5, 2019. Several offline and online sampling devices were installed at the Maidö Observatory (MO), a remote high-altitude site in the Southern Hemisphere, allowing the physical and chemical characterization of atmospheric aerosols and gases. The evaluation of short-lived gas-phase measurements allows us to conclude that air masses sampled during this period contained little or no anthropogenic influence. The dominance of sulfate and organic species in the submicron fraction of the aerosol is similar to that measured at other coastal sites.Carboxylic acids on PM10 showed a significant contribution of oxalic acid, a typical tracer of aqueous processed air masses, increasing at the end of the campaign. This result agrees with the positive matrix factorization analysis of the submicron organic aerosol, where more oxidized organic aerosols (MOOAs) dominated the organic aerosol with an increasing contribution toward the end of the campaign. Using a combination of air mass trajectories (model predictions), it was possible to assess the impact of aqueous phase processing on the formation of secondary organic aerosols(SOAs). Our results show how specific chemical signatures and physical properties of air masses, possibly affected by cloud processing, can be identified at Reunion. ́ These changes in properties are represented by a shift in aerosol size distribution to large diameters and an increased contribution of secondary sulfate and organic aerosols after cloud processing.

Published
2022

30. Measurement Report: Insights into the chemical composition of molecular clusters present in the free troposphere over the Southern Indian Ocean: observations from the Maïdo observatory (2150 m a.s.l., Reunion Island).

Author

Salignat, Romain, Rissanen, Matti, Iyer, Siddharth, Baray, Jean-Luc, Tulet, Pierre, Metzger, Jean-Marc, Brioude, Jérôme, Sellegri, Karine, and Rose, Clémence

Subjects
MOLECULAR clusters, CLOUD condensation nuclei, TIME-of-flight mass spectrometers, SULFUR cycle, ATMOSPHERIC ammonia, ATMOSPHERIC ionization, TROPOSPHERE
Abstract

New particle formation (NPF) in the free troposphere (FT) is thought to be a significant source of particles over the oceans. The entrainment of particles initially formed in the marine FT is further suspected to be a major contributor to cloud condensation nuclei (CCN) number concentrations in the marine boundary layer (BL). Yet, little is known about the process, and more broadly about the composition of the marine FT, which remains poorly explored due to access difficulties. Here we report measurements performed in April 2018 at the Maïdo observatory with a nitrate based chemical ionisation atmospheric pressure interface time-of-flight mass spectrometer, which have allowed the first molecular-level characterisation of the clusters present in the remote marine FT. A number of clusters were identified and classified into 9 groups according to their chemical composition, among which the groups containing methanesulfonic acid (MSA) and C2 amines, which show signals that are on average significantly higher when the site is under conditions representative of the marine FT (compared to the BL). The correlation analysis revealed apparent connections between the signals of the identified compounds and several variables concurrently measured at the site (under FT conditions) or related to air mass history, suggesting that oxalic acid, malonic acid and observed C2 and C4 amines could be of terrestrial origin, with, in addition, a possible marine source for oxalic acid and amines, while iodic acid, sulfur species and maleic acid have a dominant marine origin. Identification of FT conditions at the site was based on the analysis of the standard deviation of the wind direction; this parameter, which can easily be derived from continuous measurements at the site, is shown in the first part of the study to be a relevant tracer when compared to predictions from the Meso-NH atmospheric model. Similar to other high altitude sites, FT conditions are mainly encountered at night at Maïdo and therefore the link to NPF could not be established, and further research is needed to assess the composition of precursors to nanoparticle formation in the marine FT. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

33. readme.txt

Author

Noirmain, Fanny, Baray, Jean-Luc, and Tridon, Frédéric

Abstract

Read me description of the scripts

Published
2022
Full Text
View/download PDF

35. Two-year operation of the lidar1200: from fine-scale tropospheric structures to lower stratospheric water vapor detection

Author

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

Subjects
Physics, QC1-999
Abstract

The 2-year lidar water vapor database (November 2013 - October 2015) of the Maïdo Observatory (Reunion Island / 21°S,55.5°E) is now processed. The performances of the lidar in providing accurate vertical structures are shown to be good. The ability to measure quantities of a few ppmv in the lower stratosphere is demonstrated (based on Cryogenic Frost point Hygrometer sonde/lidar profiles comparisons) for a 48-hour integration time period, up to 22 km (with a vertical resolution of 1.3 km).

Published
2018
Full Text
View/download PDF

37. Insights into tropical cloud chemistry in Réunion (Indian Ocean): results from the BIO-MAÏDO campaign

Author

Dominutti, Pamela A., primary, Renard, Pascal, additional, Vaïtilingom, Mickaël, additional, Bianco, Angelica, additional, Baray, Jean-Luc, additional, Borbon, Agnès, additional, Bourianne, Thierry, additional, Burnet, Frédéric, additional, Colomb, Aurélie, additional, Delort, Anne-Marie, additional, Duflot, Valentin, additional, Houdier, Stephan, additional, Jaffrezo, Jean-Luc, additional, Joly, Muriel, additional, Leremboure, Martin, additional, Metzger, Jean-Marc, additional, Pichon, Jean-Marc, additional, Ribeiro, Mickaël, additional, Rocco, Manon, additional, Tulet, Pierre, additional, Vella, Anthony, additional, Leriche, Maud, additional, and Deguillaume, Laurent, additional

Published
2022
Full Text
View/download PDF

40. How Certain are We of the Uncertainties in Recent Ozone Profile Trend Assessments of Merged Limbo Ccultation Records? Challenges and Possible Ways Forward

Author

Hubert, Daan, Lambert, Jean-Christopher, Verhoelst, Tijl, Granville, Jose, Keppens, Arno, Baray, Jean-Luc, Cortesi, Ugo, Degenstein, D. A, Froidevaux, Lucien, Godin-Beekmann, Sophie, Hoppel, Karl, Kyrola, Erkki T, Leblanc, Thierry, Lichtenberg, Gunter, McElroy, Charles T, Murtagh, Donal P, Russell, James M., III, Salvador, Jacobo, Smit, Herman G. J, Stebel, Kerstin, Steinbrecht, Wolfgang, Strawbridge, K. B, Stubi, Rene, Swart, Daan P. J, Taha, Ghassan, Thompson, Anne M, Urban, Joachim, Van Gijsel, Anne, Von Der Gathen, Peter, Walker, Kaley Ann, Wolfram, Elian, Zawodny, Joseph M, and Nakane, Hideaki

Subjects
Meteorology And Climatology
Abstract

Most recent assessments of long-term changes in the vertical distribution of ozone (by e.g. WMO and SI2N) rely on data sets that integrate observations by multiple instruments. Several merged satellite ozone profile records have been developed over the past few years; each considers a particular set of instruments and adopts a particular merging strategy. Their intercomparison by Tummon et al. revealed that the current merging schemes are not sufficiently refined to correct for all major differences between the limb/occultation records. This shortcoming introduces uncertainties that need to be known to obtain a sound interpretation of the different satellite-based trend studies. In practice however, producing realistic uncertainty estimates is an intricate task which depends on a sufficiently detailed understanding of the characteristics of each contributing data record and on the subsequent interplay and propagation of these through the merging scheme. Our presentation discusses these challenges in the context of limb/occultation ozone profile records, but they are equally relevant for other instruments and atmospheric measurements. We start by showing how the NDACC and GAW-affiliated ground-based networks of ozonesonde and lidar instruments allowed us to characterize fourteen limb/occultation ozone profile records, together providing a global view over the last three decades. Our prime focus will be on techniques to estimate long-term drift since our results suggest this is the main driver of the major trend differences between the merged data sets. The single-instrument drift estimates are then used for a tentative estimate of the systematic uncertainty in the profile trends from merged data records. We conclude by reflecting on possible further steps needed to improve the merging algorithms and to obtain a better characterization of the uncertainties involved.

Published
2015

45. Supplementary material to "Insights into tropical cloud chemistry at Reunion Island (Indian Ocean): results from the BIO-MAÏDO campaign"

Author

Dominutti, Pamela A., primary, Renard, Pascal, additional, Vaïtilingom, Mickaël, additional, Bianco, Angelica, additional, Baray, Jean-Luc, additional, Borbon, Agnès, additional, Bourianne, Thierry, additional, Burnet, Frédéric, additional, Colomb, Aurélie, additional, Delort, Anne-Marie, additional, Duflot, Valentin, additional, Houdier, Stephan, additional, Jaffrezo, Jean-Luc, additional, Joly, Muriel, additional, Leremboure, Martin, additional, Metzger, Jean-Marc, additional, Pichon, Jean-Marc, additional, Ribeiro, Mickaël, additional, Rocco, Manon, additional, Tulet, Pierre, additional, Vella, Anthony, additional, Leriche, Maud, additional, and Deguillaume, Laurent, additional

Published
2021
Full Text
View/download PDF

46. Insights into tropical cloud chemistry at Reunion Island (Indian Ocean): results from the BIO-MAÏDO campaign

Author

Dominutti, Pamela A., primary, Renard, Pascal, additional, Vaïtilingom, Mickaël, additional, Bianco, Angelica, additional, Baray, Jean-Luc, additional, Borbon, Agnès, additional, Bourianne, Thierry, additional, Burnet, Frédéric, additional, Colomb, Aurélie, additional, Delort, Anne-Marie, additional, Duflot, Valentin, additional, Houdier, Stephan, additional, Jaffrezo, Jean-Luc, additional, Joly, Muriel, additional, Leremboure, Martin, additional, Metzger, Jean-Marc, additional, Pichon, Jean-Marc, additional, Ribeiro, Mickaël, additional, Rocco, Manon, additional, Tulet, Pierre, additional, Vella, Anthony, additional, Leriche, Maud, additional, and Deguillaume, Laurent, additional

Published
2021
Full Text
View/download PDF

47. 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

Vérèmes Hélène, Keckhut Philippe, Baray Jean-Luc, Cammas Jean-Pierre, Dionisi Davide, Payen Guillaume, Duflot Valentin, Gabarrot Franck, De Bellevue Jimmy Leclair, Posny Françoise, Evan Stéphanie, Meier Susanne, Vömel Holger, and Dirksen Ruud

Subjects
Physics, QC1-999
Abstract

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
2016
Full Text
View/download PDF

48. Analysis of volatile organic compounds during the OCTAVE campaign: sources and distributions of formaldehyde on Reunion Island

Author

Rocco, Manon, Colomb, Aurélie, Baray, Jean-Luc, Amelynck, Crist, Verreyken, Bert, Borbon, Agnès, Pichon, Jean-Marc, Bouvier, Laetitia, Schoon, Niels, Gros, Valérie, Sarda-Estève, Roland, Tulet, Pierre, Metzger, Jean-Marc, Duflot, Valentin, Guadagno, Christian, Peris, Guillaume, Brioude, Jérôme, Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Belgian Institute for Space Aeronomy / Institut d'Aéronomie Spatiale de Belgique (BIRA-IASB), Department of Inorganic and Physical Chemistry [Ghent], Universiteit Gent = Ghent University [Belgium] (UGENT), 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, 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), 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), 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), Observatoire réunionnais de l'Air (ORA), This study was supported by the project OCTAVE of the Belgian Research Action through Interdisciplinary 5 Networks (BRAIN-be) research program (2017–2021) through the Belgian Science Policy Office (BELSPO) under the contract number BR/175/A2/OCTAVE., Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), Météo France-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), 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), 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), Groupe d'étude de l'atmosphère météorologique (CNRM-GAME), Institut national des sciences de l'Univers (INSU - CNRS)-Météo France-Centre National de la Recherche Scientifique (CNRS), Équipe Troposphère, Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique, Université libre de Bruxelles (ULB)-Université libre de Bruxelles (ULB), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP), Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), 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), Université Libre de Bruxelles [Bruxelles] (ULB)-Université Libre de Bruxelles [Bruxelles] (ULB), Universiteit Gent = Ghent University (UGENT), and Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Météo-France

Subjects
volatile organic compounds (VOCs), formaldehyde sources, ISOPRENE EMISSION, COMPOUNDS VOC, BIOGENIC EMISSIONS, ANTHROPOGENIC SOURCES, IN-SITU, [SDE.MCG]Environmental Sciences/Global Changes, lcsh:QC851-999, RATIOS, TROPOSPHERE, factorization (PMF), Chemistry, positive matrix factorization (PMF), positive matrix, [SDE]Environmental Sciences, lcsh:Meteorology. Climatology, MARINE BOUNDARY-LAYER, ATMOSPHERIC CHEMISTRY, ACETALDEHYDE, kinetic chemical equations
Abstract

The Oxygenated Compounds in the Tropical Atmosphere: Variability and Exchanges (OCTAVE) campaign aimed to improve the assessment of the budget and role of oxygenated volatile organic compounds (OVOCs) in tropical regions, and especially over oceans, relying on an integrated approach combining in situ measurements, satellite retrievals, and modeling. As part of OCTAVE, volatile organic compounds (VOCs) were measured using a comprehensive suite of instruments on Reunion Island (21.07° S, 55.38° E) from 7 March to 2 May 2018. VOCs were measured at a receptor site at the Maïdo observatory during the entire campaign and at two source sites: Le Port from 19 to 24 April 2018 (source of anthropogenic emissions) and Bélouve from 25 April to 2 May 2018 (source of biogenic emissions) within a mobile lab. The Maïdo observatory is a remote background site located at an altitude of 2200 m, whereas Bélouve is located in a tropical forest to the east of Maïdo and Le Port is an urban area located northwest of Maïdo. The major objective of this study was to understand the sources and distributions of atmospheric formaldehyde (HCHO) in the Maïdo observatory on Reunion Island. To address this objective, two different approaches were used to quantify and determine the main drivers of HCHO at Maïdo. First, a chemical-kinetics-based (CKB) calculation method was used to determine the sources and sinks (biogenic, anthropogenic/primary, or secondary) of HCHO at the Maïdo site. The CKB method shows that 9% of the formaldehyde formed from biogenic emissions and 89% of HCHO had an unknown source; that is, the sources cannot be explicitly described by this method. Next, a positive matrix factorization (PMF) model was applied to characterize the VOC source contributions at Maïdo. The PMF analysis including VOCs measured at the Maïdo observatory shows that the most robust solution was obtained with five factors: secondary biogenic accounting for 17%, primary anthropogenic/solvents (24%), primary biogenic (14%), primary anthropogenic/combustion (22%), and background (23%). The main contributions to formaldehyde sources as described by the PMF model are secondary biogenic (oxidation of biogenic VOCs with 37%) and background (32%). Some assumptions were necessary concerning the high percentage of unknown HCHO sources of the CKB calculation method such as the biogenic emission factor resulting in large discrepancies between the two methods.

Published
2020

49. Interdisciplinary strategy to survey phytoplankton dynamics of a eutrophic lake under rain forcing: description of the instrumental set-up and first results.

Author

Noirmain, Fanny, Baray, Jean-Luc, Tridon, Frédéric, Cacault, Philippe, Billard, Hermine, Voyard, Guillaume, Van Baelen, Joël, and Latour, Delphine

Subjects
PHYTOPLANKTON, LAKES, AIR masses, WATER sampling, MICROCYSTIS
Abstract

We present an interdisciplinary investigation of the links between rain macro and microphysical properties, meteorological parameters, and a mountain lake to assess the impact of precipitation events on phytoplankton dynamics and, in particular, on cyanobacteria. In order to document this interdisciplinary scientific question, the Aydat lake in the French massif central mountains has been instrumented in 2020 with a set of high-resolution atmospheric radars, disdrometer, and precipitation collector. In parallel, the lake was monitored with a suite of sensors and water sampling. To illustrate the potential of this original experimental setup, we present a rain case study that occurred in September 2020 and during which three contrasted sub-periods were identified. Using our high temporal-resolution monitoring, we show that the air mass origin mainly influences the rain nutrient composition, which depends on the type of rain, convective or stratiform. Our results also highlighted a nonnegligible presence of photosynthetic cells in all rains, but their very low abundance can probably not impact the phytoplankton dynamics. Nevertheless, rain events indirectly impacted phytoplankton assemblages. Indeed, among all phytoplankton genera, three cyanobacteria, Microcystis, Coelomoron, and Merismopedia, showed a similar pattern with a systematic punctual decrease of their abundance at the lake surface immediately after rain events, suggesting a different impact of rain events according to the cyanobacterial genus considered. These various phytoplankton responses subjected to the same rainfall event could play a key role in phytoplankton dynamics in the temperate zone. Our results highlight the interest in high-frequency and time resolution monitoring of both atmosphere and lake to better understand the cyanobacteria adaptive strategies following rain events. [ABSTRACT FROM AUTHOR]

Published
2022
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results