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Rene Preusker and Rasmus Lindstrot

vertical profile of extinction and the cloud geometrical thickness are not known, the inclusion of the window channel radiance therefore allows for the correction of multiple scattering effects within the cloud layer. The retrieval algorithm is based on radiative transfer simulations using the Matrix Operator Model (MOMO; Fischer and Grassl 1984 ; Fell and Fischer 2001 ). The simulations were used to derive coefficients of a multidimensional nonlinear regression that relates the measured radiance to

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Graeme L. Stephens

1818 JOURNAL OF THE ATMOSPHERIC SCIENCES VOL. 45, NO. 12Radiative Transfer through Arbitrarily Shaped Optical Media. Part I: A General Method of Solution GRAEME L. STEPHENSColorado State University, Department of Atmospheric Science. Ft. Collins, Colorado(Manuscript received 4 August 198'/, in final form 20 January 1988) A general transform method is presented for studying problems of radiative

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Rosie Howard and Roland Stull

(trunk and needle) temperature and air temperature under these conditions. There appears to be a gap in the literature regarding the value of the water vapor mass extinction coefficient for pathlengths from zero to tens of meters. This is perhaps because there is less desire to calculate radiative transfer over these short distances or because the effects of the air are small for these pathlengths. Future work could include flux emissivity measurements or modeling using a rapid radiative transfer

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Kenneth D. Leppert II and Daniel J. Cecil

found that channels near 85 and 150 GHz appear useful for the detection of snow, and the response to snow and/or graupel increases with increasing frequency. Hong et al. (2005) found that these high-frequency channels are most sensitive to the presence of graupel, followed by cloud ice and snow. The assumption of spherical particles greatly simplifies radiative transfer simulations but is not realistic for many frozen particles. Olson et al. (2016) were able to match 165-GHz BT measurements

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Toru Nishikawa, Shigenao Maruyama, and Seigo Sakai

theoretical predictions. O'Hirok and Gautier (1998a) discussed how the discrepancy of solar absorption between three-dimensional cloud and plane-parallel cloud is ameliorated by the employment of a Monte Carlo–based three-dimensional radiative transfer model. Nowadays, the anomalous predictions are considered to have been reconciled with experiments following more precise measurements, and the current important topics in the study of atmospheric radiation have become those of cloud formation and cloud

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D. Wang, C. Prigent, L. Kilic, S. Fox, C. Harlow, C. Jimenez, F. Aires, C. Grassotti, and F. Karbou

1. Introduction The current passive microwave instruments on board meteorological satellites are limited in frequencies to 200 GHz. The Ice Cloud Imager (ICI), on board the next generation of European operational meteorological satellites [EUMETSAT Polar System Second Generation (EPS-SG)], will observe the frequencies up to 664 GHz. It will expand the current capabilities for the characterization of the cloud frozen phase, but this is challenging, as the radiative transfer models have not been

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Cenlin He, Yoshi Takano, Kuo-Nan Liou, Ping Yang, Qinbin Li, and Fei Chen

radiative transfer schemes, while the other is using empirical parameterizations derived from snow models. Previous studies have developed several parameterizations under different atmospheric conditions by assuming spherical snow grains externally mixed with impurities (e.g., Marshall and Warren 1987 ; Gardner and Sharp 2010 ; Aoki et al. 2011 ; Dang et al. 2015 ), which have been applied into global climate models (GCMs) partly for the consideration of computational efficiency. For example

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Leonhard Scheck, Martin Weissmann, and Bernhard Mayer

for some time and have been continuously improved. In most of the weather prediction centers, either the RTTOV radiative transfer package ( Saunders et al. 1999 ) or the Community Radiative Transfer Model ( Han et al. 2006 ) is used. In contrast, sufficiently fast forward operators for solar channels are only in an early development state. Thermal satellite channels provide mainly temperature and humidity information with high spatial and temporal resolution and have proven to provide valuable

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Linda Forster, Anthony B. Davis, David J. Diner, and Bernhard Mayer

optical thickness. Being based on one-dimensional (1D) radiative transfer (RT), this method applies reasonably well to extended stratiform cloud layers far away from cloud edges (e.g., Platnick et al. 2003 ; Zhang and Platnick 2011 ) but is not able to account for three-dimensional (3D) cloud morphologies driven by shallow or deep convection. This leaves a huge gap in the global observation of cloud optical properties (e.g., Cho et al. 2015 ). To close this gap, a retrieval method is needed that is

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Hirohiko Masunaga and Teruyuki Nakajima

1. Introduction Although clouds are considered to play significant roles in the earth's radiation budget, the impacts of clouds to atmospheric radiative transfer are difficult to evaluate precisely. A main uncertainty lies in the plane-parallel approximations, usually assumed in calculations of atmospheric radiative transfer, because it cannot appropriately take into account the horizontal inhomogeneity (or brokenness) of clouds. The effects on the radiation fields by brokenness of clouds have

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