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Betty Carlin, Qiang Fu, Ulrike Lohmann, Gerald G. Mace, Kenneth Sassen, and Jennifer M. Comstock

unrealistically small liquid water content to produce a realistic solar albedo as a consequence of the plane-parallel homogeneous cloud assumption (e.g., Harshvardan and Randall 1985 ). Considerable research has gone into the investigation of solar radiative transfer for horizontally inhomogeneous clouds ( Stephens 1988 ; Evans 1993 ; Cahalan et al. 1994a ; Barker 1996b ; Oreopoulos and Davies 1998a ). Techniques are being developed to correct the plane-parallel homogeneous (PPH) bias. Rescaling of the

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David A. Siegel, Toby K. Westberry, and J. Carter Ohlmann

significance of cloud color to ocean radiant heating. A simple parameterization for cloud color is developed and validated using a plane-parallel, cloudy-sky radiative transfer model. Finally, models of ocean radiation penetration, as well as in situ spectroradiometric observations, are used to quantify the role of cloud color on solar radiation penetration fluxes and ocean radiant heating rates. 2. Data and methods The Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean–Atmosphere Response Experiment

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E. Roeckner, L. Bengtsson, J. Feichter, J. Lelieveld, and H. Rodhe

in Table 2 is due to sulfate alone. Our estimate of the direct effect is slightly larger than that obtained by Kiehl and Briegleb (1993) , −0.28 W m −2 . The difference is largely due to the neglect of the spatial humidity distribution in our approach (cf. section 3c ). Both estimates are significantly smaller than that of Charlson et al. (1991) , about −0.6 W m −2 , based on a simplified radiative transfer calculation, which has been a standard method employed in climate change experiments

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Margaret A. Rozendaal, Conway B. Leovy, and Stephen A. Klein

flow, or westwardand equatorward, of the subtropical maxima in low-cloud fraction. This is qualitatively consistent with controlof the cloud amount by two competing processes in a partially decoupled cloud-topped planetary boundarylayer: heating by solar radiation absorption and advection of moist boundary layer air. A radiative transfer codehas been used to show that in eastern subtropical ocean regions, where the diurnal cycle of low clouds is largeand the cloud has a small optical thickness

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J. A. Griggs and J. E. Harries

Advanced Earth Observing Satellite ( ADEOS ) I], and analyzed the differences between clear-sky spectrally resolved OLR. Changes were detected in the spectra that, through the use of a radiative transfer model, were attributed to known changes in radiative forcing. The new data from AIRS allows us to extend this analysis to include 2003, and to compare snapshots of the atmosphere in 1970, 1997, and 2003. 2. Observations and data Spectrally resolved OLR observations at reasonably high spectral

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Jean-Louis Dufresne, Vincent Eymet, Cyril Crevoisier, and Jean-Yves Grandpeix

removing the “base” of each transition ( Clough et al. 1989 ; Mlawer et al. 2012 ). In a second step (HR_PPart code), radiative transfer is computed based on 1D (over a single line of sight) or 3D (angularly integrated) analytical expressions of spectral radiative net exchange rates and spectral radiative fluxes. We compute the radiative forcing for CO 2 and H 2 O changes on the basis of the experiments defined in Collins et al. (2006) : the reference experiment, which is the MLS atmospheric profile

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Richard Seager and Stephen E. Zebiak

radiative cooling. The important rolethat shallow convection and cloud-radiation interactions play in the spatial organization of deep convection isdemonstrated, by default, in an experiment using clear~sky radiative transfer. The modeled climate, as judged qualitatively by its simulation of quantities of importance to air-sea interaction and climate, such as the low-level wind field and precipitation, is in many ways comparable to thatachieved by much more complex GCMs. Indeed the rainfall

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H. Zhang, A. Henderson-Sellers, and K. McGuffie

. This is probablybecause evapotranspiration is the largest nonradiativecomponent in the land-surface energy budget duringthe rainy season, and a large proportion of the surfaceradiative energy is transferred to the atmosphere throughevapotranspiration. This kind of partition of surface radiative energy leads to high correlations between thechanges in evapotranspiration and sensible heat flux. Inthe dry season, the role of evapotranspiration in the surface energy balance is reduced. The link

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Spencer K. Clark, Yi Ming, Isaac M. Held, and Peter J. Phillipps

GCMs, or included neither, by using models with gray radiative transfer using prescribed shortwave and longwave optical depths. That being said, while the parameterization of clouds and convection in atmospheric models remains a challenge, and varies from model to model ( Boucher et al. 2013 ), the interaction between water vapor and radiation is better understood and more consistently represented ( Held and Soden 2000 , 2006 ). Therefore, there is reason to believe that the role of water vapor in

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Martin Wild and Erich Roeckner

Roeckner et al. (1992) and Roeckner et al. (1996) , respectively. In the longwave, ECHAM5 includes a new radiation code [Rapid Radiative Transfer Model (RRTM)] developed by Mlawer et al. (1997) . It is based on the two-stream approximation instead of the emissivity method applied in ECHAM4 ( Morcrette et al. 1986 ). The RRTM code is used in the European Centre for Medium-Range Forecasts (ECMWF) operational forecasting system ( Morcrette 2002a , b ) and has also been tested in the National Center

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