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B-J. Sohn, Seung-Hee Ham, and Ping Yang

properties of these clouds are known. The DCCs that overshoot the tropical tropopause layer (TTL) can be identified on the basis of a criterion specified in terms of infrared brightness temperature, and the characteristic optical properties of the selected DCCs can be determined. Furthermore, the inferred optical property information can be employed to simulate the top-of-atmosphere (TOA) radiances on the basis of state-of-the-art radiative transfer modeling capabilities. If these results are able to

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Benjamin H. Cole, Ping Yang, Bryan A. Baum, Jerome Riedi, Laurent C.-Labonnote, Francois Thieuleux, and Steven Platnick

with Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar ( PARASOL ) multiangle polarized reflectance measurements. The adding–doubling model of de Haan et al. (1987) is employed to simulate the polarized reflectance at the top of the atmosphere (TOA). The single-scattering properties of the ice crystals were taken from a new database that provides the spectrally consistent optical properties of ice particles from ultraviolet to far

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K. Franklin Evans, Alexander Marshak, and Tamás Várnai

results for stratocumulus compared to cumulus are probably due to the low horizontal inhomogeneity of the overcast clouds, which results in the oblique reflectances being much more related to optical depth than is the case for small cumulus clouds (see Figs. 2 and 3 ). 6. Discussion It is commonly believed that the more observations of solar radiation reflected from clouds into different directions are available, the better accuracy the retrieved cloud properties will have. However, this is not

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Juan Carlos Antuña Marrero, René Estevan Arredondo, and Boris Barja González

derive the optical and geometrical properties of CCs were implemented; the preliminary results showed very encouraging performances for measurements of CCs conducted by both CEILAP in Argentina and CLS in Cuba ( Lavorato et al. 2008 ). During Antuña's visit, in the late 2005, to the Grupo de Óptica Atmosférica (Optics Atmospheric Group) at the University of Valladolid (GOA-UVA), Spain, a letter of agreement was signed with Dr. Angel de Frutos-Baraja, chair of GOA-UVA. The goal was to establish

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Angela Benedetti and Marta Janisková

properties of liquid water clouds and Fu (1996) for those of ice clouds. For liquid water clouds, the effective radius ( r e ) is derived from the cloud liquid water content following Martin et al. (1994) , with the concentration of cloud condensation nuclei fixed at 50 cm −3 over the oceans and 900 cm −3 over the continents. For ice clouds, the effective size of the particles is a function of temperature following Ou and Liou (1995) . A detailed description of the cloud optical depth

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David L. Mitchell, Anthony J. Baran, W. P. Arnott, and C. Schmitt

. The MADA does not predict the scattering phase function of an ice particle and thus cannot calculate the asymmetry parameter, g . Rather, parameterizations of g are often combined with MADA to produce a comprehensive treatment of optical properties, such as the scheme described in Mitchell et al. (1996) . This study was conducted to provide more extensive testing of MADA and also to compare MADA with other cirrus cloud radiation schemes. In the treatment of ice cloud radiative properties, two

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Sergei M. Prigarin and Alexander Marshak

( Zuev and Titov 1995 ), to name a few. These models generally produce an unbroken (overcast) 2D x – y field of cloud optical depth or cloud liquid water path. To obtain the desired cloud fraction, a simple threshold can be used (e.g., Barker and Davies 1992 ; Marshak et al. 1998 ). The second class of cloud stochastic models provides a statistical reconstruction of an observed field and generates the detailed cloud structure. They are also called statistical cloud generators ( Venema et al. 2006

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David McKee, Jacek Piskozub, Rüdiger Röttgers, and Rick A. Reynolds

1. Introduction The propagation of light through seawater is regulated by the effect of the optical properties of the water itself and of materials suspended and dissolved within the medium. The spectral absorption a (λ) and attenuation c (λ) coefficients, where λ refers to light wavelength in vacuo, are fundamental optical characteristics of the medium that are determined only by these materials themselves and not by the structure of the light field. As such they are often referred to as

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Andrew K. Heidinger and Michael J. Pavolonis

property estimation by estimating ϵ c using an optical depth retrieval performed at 0.63 μ m (VIS) and using the value of ϵ c to estimate T c from the 11- μ m (IR) radiance. During the night, only the IR radiance is used. These approaches perform very differently for optically thin cloud. The main benefit of the split-window approach relative to the ISCCP approach is that it delivers consistent performance for all solar illumination conditions (including night) and offers an improvement to the

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Timo Nousiainen, Hannakaisa Lindqvist, Greg M. McFarquhar, and Junshik Um

wavelength. Deriving the three-dimensional shape from scattering patterns is, however, likely to be even more difficult than deriving it from two-dimensional silhouettes. Further, since the measured scattering patterns do not cover the whole scattering-angle range, the measurements do not provide the optical properties of crystals directly. However, they should provide usable references for model simulations. This study focuses on determining the shapes and single-scattering properties of small quasi

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