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H. Luce, T. Takai, T. Nakamura, M. Yamamoto, and S. Fukao

retrieved from inelastic atmospheric backscatter light by water vapor molecules. At Shigaraki Middle- and Upper-Atmosphere (MU) Observatory, a Rayleigh–Mie–Raman (RMR) lidar has been operating for measuring, in addition to humidity profiles, temperature, optical properties (backscatter and extinction coefficients) of aerosol, and cirrus cloud particle properties in the troposphere ( Behrendt et al. 2004 ). Upon appropriate calibration, the Raman lidar set up at Shigaraki provides vertical profiles of

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Philippe Keckhut, Alain Hauchecorne, Mustapha Meftah, Sergey Khaykin, Chantal Claud, and Pierre Simoneau

1. Introduction The middle atmosphere (MA) is under the conjugated influence of climate changes, due to anthropogenic activities and natural variability. This region exhibits variability on time and space with scales ranging from thousands of kilometers to tens of meters and extending in the different atmospheric layers from troposphere up to the lower thermosphere. The MA extends from the tropopause (10–15 km) to the turbopause (100–105 km) and comprises the stratosphere and mesosphere ( Blanc

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R. J. Sica, Z. A. Zylawy, and P. S. Argall

1. Introduction The determination of temperatures from Rayleigh-scattering measurements is an important remote sensing technique for temperature determination, particularly in the middle atmosphere, which is optically thin to visible light. This technique is used by Rayleigh-scatter lidar systems to retrieve temperature from photocount height profiles above the region of aerosol scattering (approximately 25 to 30 km). The retrieval of temperature from the photocount measurement is possible by

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Ellis E. Remsberg, Kenneth V. Haggard, and James M. Russell III

OCTOBER 1990 REMSBERG, HAGGARD AND RUSSELL 689Estimation of Synoptic Fields of Middle Atmosphere Parameters from Nimbus-7 LIMS Profile DataELLIS E. REMSBERG, KENNETH V. HAGGARD AND JAMES M. RUSSELL III Atmospheric Sciences Division, NASA Langley Research Center, Hampton, Virginia (Manuscript received 7 June 1989, in final form 27 March 1990)ABSTRACT The most widely used version of the Nimbus-7 LIMS middle

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P. Keckhut, A. Hauchecorne, and M. L. Chanin

850JOURNAL OF ATMOSPHERIC AND OCEANIC TECHNOLOGYVOLUME !0A Critical Review of the Database Acquired for the L~ng-Term Surveillance of the Middle Atmosphere by the French P~yleigh LidarsP. KECKHUT, A. HAUCHECORNE, AND M. L. CHANINService d;4&'onomie du CNRS, Verrieres le Buisson, France(Manuscript received 19 October 1992, in final form 19 April 1993) ABSTRACT The database obtained by Rayl-igh lidars over the south of France is now used for monitoring the

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Christophe Bellisario, Philippe Keckhut, Laurent Blanot, Alain Hauchecorne, and Pierre Simoneau

other instruments partially dedicated to the study of atmospheric chemistry ( Bertaux et al. 2010 ). The sun-synchronous satellite is located at an average altitude of 800 km, with an orbit inclination of 98.55°. It especially allows for building a 3D distribution of ozone in the middle atmosphere with high accuracy in altitude thanks to the technique of occultation of stars mainly in the stratosphere and also in the mesosphere, where the second ozone maximum was accurately observed ( Evans and

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Philippe Keckhut, Alain Hauchecorne, Mustapha Meftah, Sergey Khaykin, Chantal Claud, and Pierre Simoneau

Abstract

While meteorological numerical models extend upward to the mesopause, mesospheric observations are required for leading simulations and numerical weather forecasts and climate projections. This work reviews some of the challenges about temperature observation requirements and the limiting factors of the actual measurements associated with atmospheric tides. A new strategy is described here using the limb scattering technique based on previous experiments in space. Such observations can be placed on board cube-satellites. Technical issues are the large dynamic range (4 magnitudes) required for the measurements, the accuracy of the limb pointing and the level of stray light. The technique described here will expect accuracy of 1-2 K with a vertical resolution of 1-2 km. A constellation of 100 platforms could provide temperature observations with space (100 km) and time resolution (3 hours) recommended by the World Organization Meteorology, while tidal issues could be resolved with a minimum of 3-5 platforms with specific orbit maintained to avoid drifts.

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M. A. Kallistratova

waves. Moreover, in these experiments, detectable signals were recorded in the acoustic shadow zone. Such signals are apparently the result of pulse scattering by mesoscale inhomogeneities whose sizes are comparable with the sound wavelength. This problem of pulse scattering throughout the ABL has scarcely been studied. e. Sound scattering by anisotropic structures in the middle atmosphere Long-life mesoscale inhomogeneities (horizontally stretched and strongly anisotropic) were first revealed in

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Carl A. Mears and Frank J. Wentz

) still in operation. The MSU instruments made sounding measurements using four channels. Thermal emission from atmospheric oxygen constitutes the major component of the measured brightness temperature, with the maximum in the vertical weighting profile varying from near the surface in channel 1 to the lower stratosphere in channel 4. Channels 2, 3, and 4, which measure thick layers of the atmosphere centered in the middle troposphere, near the tropopause, and in the lower stratosphere, respectively

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H. Luce, S. Fukao, M. Yamamoto, C. Sidi, and F. Dalaudier

radar data obtained with the Doppler technique. Tsuda et al. (1986) found that the radar oblique beams must be tilted at least 10° off zenith in order to avoid the aspect sensitivity effect with the middle and upper atmosphere (MU) radar. Indeed, an underestimate of the velocity can arise when radar beams are tilted close to the zenith because of an effective zenith angle resulting from the convolution of the antenna gain pattern and the zenith angle dependence of the reflectivity ( Röttger 1981

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