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Lijuan Li, Bin Wang, and Guang J. Zhang

1. Introduction The shortwave cloud radiative forcing (SWCF) is the difference between the shortwave radiative energy fluxes under clear-sky and all-sky conditions; it has a large impact on the energy budget at the top of the atmosphere (TOA), at the surface, and in the atmosphere (e.g., Ramanathan et al. 1995 ; Tian and Ramanathan 2002 ). The annually averaged global mean SWCF at the TOA is from about −47 W m −2 ( Bacmeister et al. 2014 ) based on Clouds and the Earth’s Radiant Energy

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Bryce E. Harrop and Dennis L. Hartmann

heating from condensation and fusion declines with temperature, thus reducing the lifting capacity of saturated parcels. It is plausible that an increase in the parcel latent energy could lift the clouds above the level of clear-sky cooling and force the detraining anvil temperature to be colder than normal. To achieve greater parcel energy, we double the value of the latent heat of fusion. We demonstrate that the additional parcel energy does not go into further lifting, but instead the extra energy

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C. P. Weaver and V. Ramanathan

1. Introduction This paper investigates the relationships on large spatial scales, and daily to monthly timescales, between cloudiness, dynamics, and thermodynamics on a seasonal basis for the extratropical North Pacific and North Atlantic. Specifically, we attempt to provide a consistent model, based on the relationships between clouds and two parameters, vertical velocity, and static stability, which can be used to explain differences in cloud radiative forcing (CRF) and cloud cover within

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Mark A. Miller, Virendra P. Ghate, and Robert K. Zahn

exceptional quality and comprehensive nature of these measurements enable the radiative influence of clouds to be isolated from the radiative influence of clear skies at the column boundaries as characterized by the cloud radiative forcing (CRF) and upon the column itself (CRE). Similarly isolated output from two of the four GCMs display intriguing differences in the manner in which cloudy and clear skies are treated in both the LW and SW, and how these differences contribute to the net CRE in the models

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George P. Kablick III, Robert G. Ellingson, Ezra E. Takara, and Jlujing Gu

1. Introduction and objectives There is general agreement among atmospheric scientists that weak parameterization of interactions between radiation and clouds is responsible for much of the uncertainty in modeling the magnitude of anthropogenic influences on climate. Misrepresenting the spatial and temporal distribution of water in large-scale atmospheric models (LSAMs) will produce errors in calculated fluxes that suggest unrealistic radiative forcings. The sensitivity and uncertainty in cloud

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Nicole Albern, Aiko Voigt, David W. J. Thompson, and Joaquim G. Pinto

climate state. Nevertheless, the sum of the tropical, midlatitude and polar cloud impacts on any variable exhibits a similar structure as the global cloud impact, and the magnitude of the difference is typically below 10%. This is shown for the cloud impact on the global warming response of the zonal wind at 850 hPa ( u 850 ) in Fig. S2 . This result is consistent with the finding of Butler et al. (2010) that the response to the sum of multiple thermal forcings is larger than the response to the

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Robert Wood

clouds, with a range of microphysical and environmental forcings, cast some doubt on the ability of climate models to accurately simulate these effects. In general, the reduced cloud water sink acts to moisten and cool the MBL, lowering the cloud base. If this was the only response then increasing N d would always lead to thicker clouds as hypothesized by Albrecht (1989) , thus adding to increases in cloud reflectance from the reduced droplet size ( Twomey 1977 ). However, the decrease in

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Pavlos Kollias, Eugene E. Clothiaux, Thomas P. Ackerman, Bruce A. Albrecht, Kevin B. Widener, Ken P. Moran, Edward P. Luke, Karen L. Johnson, Nitin Bharadwaj, James B. Mead, Mark A. Miller, Johannes Verlinde, Roger T. Marchand, and Gerald G. Mace

. Ahmad , and D. Hartmann , 1989 : Cloud-radiative forcing and climate: Results from the Earth Radiation Budget Experiment . Science , 243 , 57 – 63 , doi: 10.1126/science.243.4887.57 . Sassen , K. , C. J. Grund , J. D. Spinhirne , M. H. Hardesty , and J. M. Alvarez , 1990 : The 27–28 October FIRE IFO cirrus case study: A five lidar overview of cloud structure and evolution . Mon. Wea. Rev. , 118 , 2288 – 2311 , doi: 10.1175/1520-0493(1990)118<2288:TOFICC>2.0.CO;2 . Sassen

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Tatiana A. Tarasova and Iracema F. A. Cavalcanti

SRB surface solar radiative fluxes and shortwave cloud radiative forcing over South America. The similar space resolution of the satellite-derived and model-simulated surface fluxes allows detailed comparisons. The scarcity of ground-based pyranometer measurements over South America is another reason to use the SRB datasets. Despite the errors related to approximate methods of surface flux derivation from satellite data, strong correlation between the upward flux at the top of the earth

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Xianglei Huang, Jason N. S. Cole, Fei He, Gerald L. Potter, Lazaros Oreopoulos, Dongmin Lee, Max Suarez, and Norman G. Loeb

NASA’s Modeling Analysis and Prediction program managed by Dr. D. Considine. REFERENCES Allan , R. P. , and M. A. Ringer , 2003 : Inconsistencies between satellite estimates of longwave cloud forcing and dynamical fields from reanalyses . Geophys. Res. Lett. , 30 , 1491 , doi:10.1029/2003GL017019 . Allan , R. P. , M. A. Ringer , J. A. Pamment , and A. Slingo , 2004 : Simulation of the Earth’s radiation budget by the European Centre for Medium-Range Weather Forecasts 40-year

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