Development and deployment of autonomous LiDAR set on drifting buoys to study aerosols and clouds Arctic properties, and induced radiative forcing

• Main Author: Mariage, Vincent
• Other Authors: 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 Pierre et Marie Curie - Paris VI, Jacques Pelon
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2015
• Subjects: LiDAR; Arctic; Clouds; Arctique; Aérosols; Nuages; Bilan radiatif; Autonome; Bouée; [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]; North Pole; Arctique*; Sea ice
• Online Access: https://tel.archives-ouvertes.fr/tel-01334040; https://tel.archives-ouvertes.fr/tel-01334040/document; https://tel.archives-ouvertes.fr/tel-01334040/file/these_archivage_3270914o.pdf

To improve our knowledge of the processes and interactions which occur in Arctic between atmosphere, sea ice and ocean, an EQUIPEX funding was granted to the IAOOS project. This improvement will be reached by deploying a network of multi-instrumented buoys. For the atmospheric analyses an innovative backscattering LiDAR meeting with constraints of the project and arctic environment has been developed. An analytical model of signal to noise ratio in clear sky led to the instrumental key parameters, and numerical simulations helped in improving the system performances. An evolutive prototype has been realized within the tight planning of this EQUIPEX. The first whole equiped buoy was deployed close to the north pole in April 2014 and worked until the beginning of December 2014. A second deployment of two buoys, including a polarized version, was then realized within the N-ICE campaign from January to June 2015. These first campaigns gave first statistics of aerosols and clouds distribution in the central arctic region with an autonomous LiDAR. First results show frequent aerosols layers in mid-troposphere during spring, as well as a high occurence of very low clouds. LiDAR measurements were also used to estimate downwelling longwave and shortwave at surface. Results obtained from these first deployments and comparisons with analysis and outputs from the WRF model show a first overview of what can be expected from this network of multi-instrumented buoys in the central arctic region. Afin de mieux comprendre les processus et les interactions entre l'atmosphère, la glace de mer et l'océan en arctique, un financement EQUIPEX a permis de développer et déployer le projet IAOOS (Ice-Atmosphere-Ocean-Observing-System) de réseau de bouées multi-instrumentées. Pour la partie atmosphère un LiDAR rétrodiffusion innovant a été développé pour répondre aux contraintes du projet et de l'environnement arctique. Un modèle analytique du rapport signal sur bruit en air clair a permis de préciser les paramètres clés de la ...