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  1. AU="Patrick Rairoux"
  2. AU=Lanna Alessio
  3. AU="Fusco, Augusto"
  4. AU="Mahboobe Hosseinikia"
  5. AU="Stone, G"
  6. AU="Seuthe, Leni Katharina"
  7. AU="Schuetz, Thomas J"
  8. AU="Thielen, Peter"
  9. AU="Anders Tveita"
  10. AU="Joseph O. Fadare"
  11. AU="Koech, O K"
  12. AU="Kapp, William"
  13. AU="Argañaraz, Gustavo A."
  14. AU="Winters, Adrienna"
  15. AU="Iman Mamdouh Talaat"
  16. AU="Benjamin Kingsley Harley"
  17. AU="Cirio, Maria Cecilia"
  18. AU="Rodriguez-Rodriguez, Alvaro Manuel"
  19. AU="Anna Maria Aloisi"
  20. AU="Na, Li"
  21. AU="Beatriz Aguiar Jordão Paranhos"
  22. AU="johnson, Michael"
  23. AU=Hunt S A
  24. AU="Gniazdowski, Victoria"
  25. AU="Griffin, Matthew E"
  26. AU="Bean, Paris"
  27. AU="Elomaa, Paula"
  28. AU="Robert Fowler"
  29. AU="Nielsen, Stine"
  30. AU="Chabartier, Cyrille"

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  1. Artikel ; Online: Laboratory Evaluation of the (355, 532) nm Particle Depolarization Ratio of Pure Pollen at 180.0° Lidar Backscattering Angle

    Danaël Cholleton / Patrick Rairoux / Alain Miffre

    Remote Sensing, Vol 14, Iss 3767, p

    2022  Band 3767

    Abstract: While pollen is expected to impact public human health and the Earth’s climate more and more in the coming decades, lidar remote sensing of pollen has become an important developing research field. To differentiate among the pollen taxa, a polarization ... ...

    Abstract While pollen is expected to impact public human health and the Earth’s climate more and more in the coming decades, lidar remote sensing of pollen has become an important developing research field. To differentiate among the pollen taxa, a polarization lidar is an interesting tool since pollen exhibit non-spherical complex shapes. A key attribute is thus the lidar particle depolarization ratio ( PDR ) of pollen, which is however difficult to quantify as pollen are large and complex-shaped particles, far beyond the reach of light scattering numerical simulations. In this paper, a laboratory π-polarimeter is used to accurately evaluate the PDR of pure pollen, for the first time at the lidar exact backscattering angle of 180.0°. We hence reveal the lidar PDR of pure ragweed, ash, birch, pine, cypress and spruce pollens at 355 and 532 nm lidar wavelengths, as presented at the ELC 2021 conference. A striking result is the spectral dependence of the lidar PDR , highlighting the importance of dual-wavelength (or more) polarization lidars to identify pollen taxa. These spectral and polarimetric fingerprints of pure pollen, as they are accurate, can be used by the lidar community to invert multi-wavelength lidar polarization measurements involving pollen.
    Schlagwörter lidar particle depolarization ratio ; pure pollen ; polarization lidar ; laboratory ; Science ; Q
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2022-08-01T00:00:00Z
    Verlag MDPI AG
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel ; Online: Towards DCS in the UV Spectral Range for Remote Sensing of Atmospheric Trace Gases

    Sandrine Galtier / Clément Pivard / Patrick Rairoux

    Remote Sensing, Vol 12, Iss 3444, p

    2020  Band 3444

    Abstract: The development of increasingly sensitive and robust instruments and new methodologies are essential to improve our understanding of the Earth’s climate and air pollution. In this context, Dual-Comb spectroscopy (DCS) has been successfully demonstrated ... ...

    Abstract The development of increasingly sensitive and robust instruments and new methodologies are essential to improve our understanding of the Earth’s climate and air pollution. In this context, Dual-Comb spectroscopy (DCS) has been successfully demonstrated as a remote laser-based instrument to probe infrared absorbing species such as greenhouse gases. We present here a study of the sensitivity of Dual-Comb spectroscopy to remotely monitor atmospheric gases focusing on molecules that absorb in the ultraviolet domain, where the most reactive molecules of the atmosphere (OH, HONO, BrO.) have their highest absorption cross-sections. We assess the achievable signal-to-noise ratio (SNR) and the corresponding minimum absorption sensitivity of DCS in the ultraviolet range. We propose a potential light source for remote sensing UV-DCS and discuss the degree of immunity of UV-DCS to atmospheric turbulences. We show that the characteristics of the currently available UV sources are compatible with the unambiguous identification of UV absorbing gases by UV-DCS.
    Schlagwörter remote-sensing ; dual-comb spectroscopy ; UV light source ; air quality monitoring ; atmospheric pollution ; LIDAR ; Science ; Q
    Thema/Rubrik (Code) 535
    Sprache Englisch
    Erscheinungsdatum 2020-10-01T00:00:00Z
    Verlag MDPI AG
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  3. Artikel ; Online: Remote Sensing Observation of New Particle Formation Events with a (UV, VIS) Polarization Lidar

    Alain Miffre / Danaël Cholleton / Tahar Mehri / Patrick Rairoux

    Remote Sensing, Vol 11, Iss 15, p

    2019  Band 1761

    Abstract: Observations of new particle formation events in free troposphere are rather seldom and limited in time and space, mainly due to the complexity and the cost of the required on-board instrumentation for airplane field campaigns. In this paper, a ... ...

    Abstract Observations of new particle formation events in free troposphere are rather seldom and limited in time and space, mainly due to the complexity and the cost of the required on-board instrumentation for airplane field campaigns. In this paper, a calibrated (UV, VIS) polarization elastic lidar (2β + 2δ) is used to remotely sense new particle formation events in the free troposphere in the presence of mineral dust particles. Using very efficient (UV, VIS) light polarization discriminators (1:10 7 ) and after robust calibration, the contribution of mineral dust particles to the co-polarized (UV, VIS) lidar channels could be removed, to reveal the backscattering coefficient of the newly nucleated particles after these numerous particles have grown to a size detectable with our lidar. Since our polarization and wavelength cross-talks are fully negligible, the observed variation in the (UV, VIS) particle backscattering time−altitude maps could be related to variations in the particle microphysics. Hence, day and nighttime differences, at low and high dust loadings, were observed in agreement with the observed nucleation process promoted by mineral dust. While light backscattering is more sensitive to small-sized particles at the UV lidar wavelength of 355 nm, such new particle formation events are here for the first time also remotely sensed at the VIS lidar wavelength of 532 nm at which most polarization lidars operate. Moreover, by addressing the (UV, VIS) backscattering Angstrom exponent, we could discuss the particles’ sizes addressed with our (UV, VIS) polarization lidar. As nucleation concerns the lowest modes of the particles’ size distribution, such a methodology may then be applied to reveal the lowest particle sizes that a (UV, VIS) polarization lidar can address, thus improving our understanding of the vertical and temporal extent of nucleation in free troposphere, where measurements are rather seldom.
    Schlagwörter lidar ; polarization ; spectroscopy ; nucleation ; Angstrom exponent ; Science ; Q
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsdatum 2019-07-01T00:00:00Z
    Verlag MDPI AG
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel: Investigating the size, shape and surface roughness dependence of polarization lidars with light-scattering computations on real mineral dust particles: Application to dust particles' external mixtures and dust mass concentration retrievals

    Mehri, Tahar / Alain Miffre / Grégory David / Hannakaisa Lindqvist / Jani Tyynelä / Osku Kemppinen / Patrick Rairoux / Timo Nousiainen

    Atmospheric research. 2018 May 01, v. 203

    2018  

    Abstract: Our understanding of the contribution of mineral dust to the Earth's radiative budget is limited by the complexity of these particles, which present a wide range of sizes, are highly-irregularly shaped, and are present in the atmosphere in the form of ... ...

    Abstract Our understanding of the contribution of mineral dust to the Earth's radiative budget is limited by the complexity of these particles, which present a wide range of sizes, are highly-irregularly shaped, and are present in the atmosphere in the form of particle mixtures. To address the spatial distribution of mineral dust and atmospheric dust mass concentrations, polarization lidars are nowadays frequently used, with partitioning algorithms allowing to discern the contribution of mineral dust in two or three-component particle external mixtures. In this paper, we investigate the dependence of the retrieved dust backscattering (βd) vertical profiles with the dust particle size and shape. For that, new light-scattering numerical simulations are performed on real atmospheric mineral dust particles, having determined mineralogy (CAL, DOL, AGG, SIL), derived from stereogrammetry (stereo-particles), with potential surface roughness, which are compared to the widely-used spheroidal mathematical shape model. For each dust shape model (smooth stereo-particles, rough stereo-particles, spheroids), the dust depolarization, backscattering Ångström exponent, lidar ratio are computed for two size distributions representative of mineral dust after long-range transport. As an output, two Saharan dust outbreaks involving mineral dust in two, then three-component particle mixtures are studied with Lyon (France) UV–VIS polarization lidar. If the dust size matters most, under certain circumstances, βd can vary by approximately 67% when real dust stereo-particles are used instead of spheroids, corresponding to variations in the dust backscattering coefficient as large as 2Mm−1·sr−1. Moreover, the influence of surface roughness in polarization lidar retrievals is for the first time discussed. Finally, dust mass-extinction conversion factors (ηd) are evaluated for each assigned shape model and dust mass concentrations are retrieved from polarization lidar measurements. From spheroids to stereo-particles, ηd increases by about 30%. We believe these results may be useful for our understanding of the spatial distribution of mineral dust contained in an aerosol external mixture and to better quantify dust mass concentrations from polarization lidar experiments.
    Schlagwörter aerosols ; algorithms ; dust ; lidar ; light scattering ; mathematical models ; mineralogy ; particle size ; surface roughness ; France
    Sprache Englisch
    Erscheinungsverlauf 2018-0501
    Umfang p. 44-61.
    Erscheinungsort Elsevier B.V.
    Dokumenttyp Artikel
    ISSN 0169-8095
    DOI 10.1016/j.atmosres.2017.11.027
    Datenquelle NAL Katalog (AGRICOLA)

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  5. Artikel ; Online: MERLIN

    Gerhard Ehret / Philippe Bousquet / Clémence Pierangelo / Matthias Alpers / Bruno Millet / James Abshire / Heinrich Bovensmann / John Burrows / Frédéric Chevallier / Philippe Ciais / Cyril Crevoisier / Andreas Fix / Pierre Flamant / Christian Frankenberg / Fabien Gibert / Birgit Heim / Martin Heimann / Sander Houweling / Hans Hubberten /
    Patrick Jöckel / Kathy Law / Alexander Löw / Julia Marshall / Anna Agusti-Panareda / Sebastien Payan / Catherine Prigent / Patrick Rairoux / T. Sachs / Marko Scholze / Martin Wirth

    Remote Sensing

    A French-German Space Lidar Mission Dedicated to Atmospheric Methane

    2017  

    Erscheinungsland de
    Dokumenttyp Artikel ; Online
    DOI 10.3390/rs9101052
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  6. Artikel ; Online: MERLIN

    Gerhard Ehret / Philippe Bousquet / Clémence Pierangelo / Matthias Alpers / Bruno Millet / James B. Abshire / Heinrich Bovensmann / John P. Burrows / Frédéric Chevallier / Philippe Ciais / Cyril Crevoisier / Andreas Fix / Pierre Flamant / Christian Frankenberg / Fabien Gibert / Birgit Heim / Martin Heimann / Sander Houweling / Hans W. Hubberten /
    Patrick Jöckel / Kathy Law / Alexander Löw / Julia Marshall / Anna Agusti-Panareda / Sebastien Payan / Catherine Prigent / Patrick Rairoux / Torsten Sachs / Marko Scholze / Martin Wirth

    Remote Sensing, Vol 9, Iss 10, p

    A French-German Space Lidar Mission Dedicated to Atmospheric Methane

    2017  Band 1052

    Abstract: The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and ... ...

    Abstract The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently scheduled for the timeframe 2021/22. The German Space Agency (DLR) is responsible for the payload, while the platform (MYRIADE Evolutions product line) is developed by the French Space Agency (CNES). The main scientific objective of MERLIN is the delivery of weighted atmospheric columns of methane dry-air mole fractions for all latitudes throughout the year with systematic errors small enough (<3.7 ppb) to significantly improve our knowledge of methane sources from global to regional scales, with emphasis on poorly accessible regions in the tropics and at high latitudes. This paper presents the MERLIN objectives, describes the methodology and the main characteristics of the payload and of the platform, and proposes a first assessment of the error budget and its translation into expected uncertainty reduction of methane surface emissions.
    Schlagwörter MERLIN ; space mission ; IPDA Lidar ; atmospheric methane ; CH4 emissions ; global methane budget ; Science ; Q
    Sprache Englisch
    Erscheinungsdatum 2017-10-01T00:00:00Z
    Verlag MDPI AG
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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