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Ralf Bennartz and Grant W. Petty

hydrometeor profiles from the radar data and is described in section 2 . Based on Mie calculations for different size factors, precipitation rates, and particle densities, we investigate the relative effect of these parameters on microwave optical properties ( section 3 ). In section 4 we apply the new method to three different precipitation events and evaluate the relative effect of ice particle size and density. The precipitation events were observed during the Baltic Sea Experiment–Pilot Study for

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Ming Liu, Young-Joon Kim, and Qingyun Zhao

-stream scattering-absorption approximation for solar radiation but neglects cloud scattering for thermal IR radiation. The cloud optical property parameterization has no dependence on cloud effective radius. These simplifications were originally introduced for increasing the computational efficiency of weather forecast and climate prediction by speeding up flux calculations with a simplified cloud–radiation interaction approach at a coarse spectral resolution of three shortwave (SW) and five longwave (LW) bands

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P. Koepke and K. T. Kriebel

1985, in final form 16 October 1986) The shortwave radiation field, i.e., in the solar spectral range, emerging at the top of the atmosphere isanisotropic due to the optical properties of the atmosphere and the reflectance characteristics of the underlyingsurface. Thus, anisotropy conversion factorsare used to account for anisotropy in the derivation of flux densitiesfrom satellite measured broadband radiances. Uncertainties in the conversion factors due to uncertainties ofthe actual parameters

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J. R. Garratt, A. B. Pittock, and K. Walsh

high-altitude smoke layer has beeninvestigated in a mesoscale numerical model of the atmosphere. Emphasis is placed on the changes in meanboundary-layer structure and near-surface temperatures when smoke of absorption optical depth (AOD) in the,range 0 to 1 is introduced. Calculations have been made at 30-S, for different soil thermal properties and degreesof surface wetness, over a time period of several days during which major smoke-induced cooling occurs. Thepresence of smoke reduces the daytime

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Sebastian Bley, Hartwig Deneke, and Fabian Senf

polar-orbiting satellites, geostationary satellites like Meteosat have the capability to observe and track cumulus clouds from their early developing stage onward and are the focus of the present study. Separating cloudy from cloud-free areas is an essential first step in the retrieval of cloud physical properties from satellite. Roebeling et al. (2006) developed an algorithm to retrieve the cloud optical thickness ( τ ), the cloud droplet effective radius ( ), and the liquid water path (LWP) from

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Anne Garnier, Jacques Pelon, Philippe Dubuisson, Ping Yang, Michaël Faivre, Olivier Chomette, Nicolas Pascal, Pat Lucker, and Tim Murray

spectral signature of cirrus clouds in this domain, which is related to the varying absorption by ice ( Warren 1984 ; Warren and Brandt 2008 ), the cirrus microphysical properties, and meteorological and surface parameters. The spectral signature has been analyzed in terms of interchannel brightness temperature differences (BTD) by using radiative transfer models to simulate the observations and ultimately retrieve the cloud optical and microphysical properties from daytime or nighttime operation

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Oliver Schlenczek, Jacob P. Fugal, Gary Lloyd, Keith N. Bower, Thomas W. Choularton, Michael Flynn, Jonathan Crosier, and Stephan Borrmann

. , B. A. Baker , P. Zmarzly , D. O’Connor , Q. Mo , J.-F. Gayet , and V. Shcherbakov , 2006a : Microphysical and optical properties of atmospheric ice crystals at South Pole Station . J. Appl. Meteor. Climatol. , 45 , 1505 – 1524 , doi: 10.1175/JAM2421.1 . 10.1175/JAM2421.1 Lawson , R. P. , D. O’Connor , P. Zmarzly , K. Weaver , B. Baker , Q. Mo , and H. Jonsson , 2006b : The 2D-S (stereo) probe: Design and preliminary tests of a new airborne, high

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Michael P. Jensen and Anthony D. Del Genio

and anvils act as a “thermostat” for tropical ocean temperatures. As the sea surface temperature (SST) increases, deep convective activity increases, resulting in more anvil outflow with greater optical thickness. This increases the cloud albedo which, in turn, decreases the solar energy absorbed by the ocean surface, regulating sea surface temperatures. More recently, Lindzen et al. (2001) suggest that warmer SSTs result in more efficient conversion of growing droplets to precipitation

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Claude E. Duchon and James S. Goerss

company and operate by electrically cooling a metal mirror until a film of water vapor or frost is optically detected on the mirrored surface. The ratio of the signal to noise variance was found to vary betweenabout 10:1 and 100:1 at the origin and decrease to zero between about 0.15 and 0.3 Hz, both properties dependent on atmospheric conditions and the structure of system noise. Since the data were collected once persecond, appropriate filtering and decimation could be performed for archiving

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H. E. Gerber

thin mirror on which condensation is controlled by limitingthe exchange of ambient water vapor to condensation sites consisting of sized submicron salt nuclei.The salt-solution droplets formed on the nuclei are prevented from exceeding a reference size by heatingthe mirror with infrared diodes which are part ofa thermo-optical servo system. The temperature increaseof the mirror is directly related to the ambient relative humidity. The performance of the hygrometer is modeled for the hypothetical

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