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Chen Zhou, Ping Yang, Andrew E. Dessler, Yongxiang Hu, and Bryan A. Baum

semiwidth and length of a hexagonal ice crystal. The size distribution of HOIC is the same as that in ROIC, except that only plates with a size greater than 100 μ m are considered to be quasi-horizontally oriented since smaller plates can have large tilt angles ( Klett 1995 ). Subsequently, the phase matrix is normalized before being used in the Monte Carlo radiative transfer simulations. Fig . 2. Illustration of the scattering coordinates and scattering angles. The forward amplitude matrix is used to

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Eli J. Mlawer, Michael J. Iacono, Robert Pincus, Howard W. Barker, Lazaros Oreopoulos, and David L. Mitchell

drives the large-scale dynamics that moves energy from the tropics toward the poles. Radiation calculations are therefore essential for climate and weather simulations, but are themselves quite complex even without considering the effects of variable and inhomogeneous clouds. Clear-sky radiative transfer calculations have to account for thousands of absorption lines due to water vapor, carbon dioxide, and other gases, which are irregularly distributed across the spectrum and have shapes dependent on

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Howard W. Barker, Jason N. S. Cole, Jiangnan Li, Bingqi Yi, and Ping Yang

GCMs. Paralleling over three decades of widespread usage of two streams in GCMs, numerous studies have demonstrated the shortcomings of 1D solutions of the solar radiative transfer equation in general, with particular emphases on common two-stream approximations. The focus has been on demonstrating their limitations at representing either details of particulate optical properties (e.g., King and Harshvardhan 1986 ; Li and Ramaswamy 1996 ; Räisänen 2002 ) or their neglect of horizontal radiative

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Ming-Dah Chou, Jack Chung-Chieh Yu, Wei-Liang Lee, Chein-Jung Shiu, Kyu-Tae Lee, Il-Sung Zo, Joon-Bum Jee, and Bu-Yo Kim

1. Introduction In the thermal infrared [longwave (LW)], the absorption coefficient k varies rapidly with wavenumber ν . Within a spectral band with a width of, say, 100 cm −1 , the absorption coefficient might vary by many orders of magnitude. Accurate calculations of radiative transfer would require division of the spectral band into tens of thousands of intervals and treatment of each interval as monochromatic. This would lead to formidable computational burden if repeated calculations of

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Nadir Jeevanjee and Stephan Fueglistaler

1. Introduction The cooling-to-space approximation is a venerable tool of radiative transfer. Formulated over 50 years ago (M. Zagoni 2016, unpublished manuscript; Green 1967 ; Rodgers and Walshaw 1966 ), it gives a simplified description of radiative cooling suitable for textbooks ( Wallace and Hobbs 2006 ; Petty 2006 ; Thomas and Stamnes 2002 ), heuristics and idealized modeling ( Jeevanjee and Fueglistaler 2020 ; Jeevanjee and Romps 2018 ), and has served in the past as a basis for

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Feng Zhang, Kun Wu, Jiangnan Li, Quan Yang, Jian-Qi Zhao, and Jian Li

1. Introduction The radiative transfer equation (RTE), which describes the radiative transfer process, is an integro-differential equation. Many approximative methods have been developed to solve RTE (e.g., Chandrasekhar 1950 ; Liou 1974 ; Coakley and Chýlek 1975 ; Wiscombe 1977 ; Meador and Weaver 1980 ; Liou et al. 1988 ; Toon et al. 1989 ; Shibata and Uchiyama 1992 ; Li and Ramaswamy 1996 ; Fu et al. 1997 ; Zhang et al. 2010 ; van Oss and Spurr. 2002 ; Lin et al. 2013 ; Zhang

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Zhonghai Jin and Andrew Lacis

1. Introduction Clouds have very important effect on Earth’s radiation budget of the atmosphere, thus making clouds one of the fundamental issues in the study and modeling of the climate. Accurate computation of radiative fluxes and absorption in clouds is needed to assess their impact on climate, but rigorous radiative transfer computations (e.g., Hansen and Travis 1974 ) are only feasible in the framework of plane-parallel homogeneous (PPH) geometry. In contrast, surface and space

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Christopher W. O’Dell, Andrew K. Heidinger, Thomas Greenwald, Peter Bauer, and Ralf Bennartz

1. Introduction There is currently a need for fast yet accurate radiative transfer (RT) models for scattering atmospheres. Numerical weather prediction (NWP) models rely increasingly on assimilation of radiance data directly, rather than on derived products ( English et al. 2000 ). Operational centers are beginning to contemplate assimilating microwave and infrared radiances under all-weather conditions, instead of under clear skies only, as is currently done ( Greenwald et al. 2002 ). For this

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Timothy W. Cronin

and setting). The top-of-atmosphere incident solar radiation per unit ground area, or insolation, is simply the product of the solar constant S 0 and the cosine of the solar zenith angle, μ ≡ cos ζ : where the planetary-mean insolation is simply 〈 I 〉 = S 0 /4 ≈ 342 W m −2 (in this paper, we will denote spatial averages with 〈 x 〉 and time averages with ). A global-average radiative transfer calculation requires specifying both an effective cosine of solar zenith angle μ * and an effective

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Andrew K. Heidinger and Stephen K. Cox

1 APRIL 1996 HEIDINGER AND COX 953Finite-Cloud Effects in Longwave Radiative Transfer ANDREW K. HEIDINGER AND STEPHEN K. COXDepartment of Atmospheric Science, Colorado State University, Fort Collins, Colorado(Manuscript received 13 March 1995, in final form 28 September 1995)ABSTRACT As numerical weather and climate prediction models demand more accurate treatment of clouds

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