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Howard W. Barker

VOL. 51, NO. 9 JOURNAL OF THE ATMOSPHERIC SCIENCES 1MAY1994Solar Radiative Transfer for Wind-Sheared Cumulus Cloud Fields HowAm~ W. BA~I~RAtmospheric Environment Service, Climate Modelling and Analysis Division, University of Victoria, Victoria, British Columbia, Canada(Manuscript received 19 May 1993, in final form 31 August 1993) ABSTRACT The Monte Carlo method of

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K. Franklin Evans, Alexander Marshak, and Tamás Várnai

1. Introduction Operational solar reflectance cloud retrieval techniques still use one-dimensional (1D) radiative transfer theory (e.g., Nakajima and King 1990 ). Numerous theoretical studies based on increasingly realistic cloud fields have shown that the retrieval accuracy of optical depth can be poor for broken clouds or for stratiform clouds with oblique solar or viewing angles due to three-dimensional (3D) radiative transfer effects ( Chambers et al. 1997 ; Loeb et al. 1998 ; Zuidema

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Alexandra L. Jones and Larry Di Girolamo

1. Introduction Radiative transfer models are needed to compute the net radiation absorbed by Earth’s atmosphere and surface and the radiation reaching our remote sensors. The plane-parallel approximation, which assumes the atmosphere and its radiative boundary conditions are horizontally homogeneous, is used ubiquitously in computing radiative heating and photolysis rates in environmental prediction models. This approximation simplifies the radiative transfer calculation to one dimension (1D

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David A. Rutan, Seiji Kato, David R. Doelling, Fred G. Rose, Le Trang Nguyen, Thomas E. Caldwell, and Norman G. Loeb

more complex than at the TOA, as it requires a radiative transfer model and satellite-derived properties of clouds and aerosols and atmospheric state from either satellites or reanalysis. Underlying assumptions in the radiative transfer model calculations and ancillary input data error increases the uncertainty in the surface radiation budget estimates. Furthermore, it is known that the diurnal cycle of clouds and their contribution to the diurnal cycle of surface radiant flux must be taken into

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K. Franklin Evans

1. Introduction Observations (e.g., Harrison et al. 1990 ) have confirmed that clouds have a large impact on the radiative energy flows in the atmosphere. Besides the problem of predicting the distribution of cloud properties, one difficulty in modeling radiative transfer in clouds has been the ubiquitous inhomogeneity of clouds. Almost no cloud fields on Earth are horizontally uniform, which is the assumption of plane-parallel models that are the mainstay of atmospheric radiative transfer

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Nicolas Ferlay and Harumi Isaka

1. Introduction Since the early 1990s, there have been many publications devoted to the study of radiative transfer in inhomogeneous clouds. The subject of some of these studies, which is germane to the present work, is the accounting of the effects of cloud inhomogeneity, within the framework of plane-parallel radiative transfer. When inhomogeneous clouds are assumed homogenous over a given scale within a plane-parallel framework, a bias in the radiances and radiative fluxes results, known as

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Salvador Matamoros, Josep-Abel González, and Josep Calbó

obtain routine measurements of the aerosol optical depth ( Harrison et al. 1994 ; Harrison and Michalsky 1994 ). To obtain cloud properties, the Min and Harrison algorithm ( Min and Harrison 1996a ; Min and Harrison 1996b , hereinafter MH96 ), uses an iterative process based on an inversion of the adjoint treatment of the radiative transfer. This treatment allows us to obtain the atmospheric transmittance for any solar angle in a single computation. The MH96 method has been applied to

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Takashi Y. Nakajima, Kentaroh Suzuki, and Graeme L. Stephens

the abovementioned questions, the goal of this study and that of Nakajima et al. (2010 , hereafter Part II) is to show how the CDR information, by coupling to the CPR of CloudSat as discussed in Part II , relates to droplet growth and the transition to rain in warm water clouds. This paper focuses on the sensitivity studies using radiative transfer models designed to elucidate the possible mechanisms that produce the observed differences in R16, R21, and R37. We also show that the

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Thomas Birner

stratospheric dynamics on tropopause height and lower stratospheric static stability will be further investigated using offline radiative transfer calculations. Concerning the static stability structure around the tropopause and in the lower stratosphere, it will prove insightful to assess the vertical structure of the residual circulation around the tropopause. In particular, the midlatitudinal residual circulation undergoes structural changes around the tropopause. It will be shown in the present study

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Rafał Wójcik, Konstantinos Andreadis, Marco Tedesco, Eric Wood, Tara Troy, and Dennis Lettenmeier

retrieval of atmospheric moisture in which the SWE problem is incidental. However, even where there is a motivation to update land surface variables, such as SWE, the assimilation of brightness temperatures ( T b ), rather than derived the SWE products, requires knowledge of snow physical properties because they affect the (surface) emissivity. National Centers for Environmental Prediction (NCEP) operational models currently use the Community Radiative Transfer Model (CRTM), which predicts TOA microwave

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