Jean-Baptiste Renard

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Scintillation effects are not negligible in the stratosphere. We present a model based on a 3D model of anisotropic and isotropic refractive index fluctuations spectra that predicts scintillation rates within the so-called small perturbation approximation. Atmospheric observations of stellar scintillation made from the AMON-RA (AMON, Absorption par les(More)
A new, light balloonborne UV-visible spectrometer, called SALOMON, is designed to perform nighttime measurements of stratospheric trace-gas species by using the Moon as a light source. The first flight, performed on 31 October 1998 at mid-latitude with a float altitude of 26.7 km, allowed the performance of the pointing system to be checked and vertical(More)
Aerosol extinction coefficients have been derived in the 375-700-nm spectral domain from measurement in the stratosphere since 1992, at night, at mid- and high latitudes from 15 to 40 km, by two balloonborne spectrometers, Absorption par les Minoritaires Ozone et NO(chi) (AMON) and Spectroscopie d'Absorption Lunaire pour l'Observation des Minoritaires Ozone(More)
The physical properties of stratospheric aerosols can be retrieved from optical measurements involving extinction, radiance, polarization, and counting. We present here the results of measurements from the balloonborne instruments AMON, SALOMON, and RADIBAL, and from the French Laboratoire de Météorologie Dynamique and the University of Wyoming balloonborne(More)
A new version of the PROGRA2 instrument, dedicated to measuring the polarization phase function of various kinds of solid particles, allows obtaining maps of polarization and brightness with a spatial resolution of a few tens of micrometers. The measurements are conducted in microgravity during parabolic flights to ensure random distribution and orientation(More)
The aerosol extinction measurements in the ultraviolet and visible wavelengths by the balloonborne spectrometer Spectroscopie d'Absorption Lunaire pour l'Observation des Minoritaires Ozone et NOx (SALOMON) show that aerosols are present in the middle stratosphere, above 25-km altitude. These observations are confirmed by the extinction measurements(More)
Measuring linear polarization of light scattered by a cloud of particles can help retrieve their physical properties. We present an extensive study of polarimetric measurements of sand grains that can be found on the surface and in the atmosphere of the Earth. Different techniques of measurements are compared using the Laboratoire de Météorologie Physique(More)
The UV-visible spectrometer SALOMON, dedicated to the retrieval of vertical profiles of O3, NO2 and NO3, has performed measurements on 19 September 2002, from Aire sur l’Adour (France) between 20h00 and 22h30 TU. At the same time, an ozone sounding has been launched. GOMOS has performed measurements at 21h24 UT, with a spatial coincidence with SALOMON and(More)