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Hi Ku Cho, Jhoon Kim, Yeonjin Jung, Yun Gon Lee, and Bang Yong Lee

sky, and clear sky. The difference between the cloudy-sky flux and clear-sky flux is defined as cloud radiative forcing (e.g., Ramanathan et al. 1989 ; Town et al. 2005 ). Thus DLR cloud forcing (DLR CF) at the surface is given by where F ↓ is the DLR, and the subscripts, “all” and “clear” refer to all-sky and clear-sky (cloud free) conditions. Table 4 shows the DLR CF of 52 W m −2 (23%) from the fact that annual mean DLR is 228 W m −2 for clear sky and 280 W m −2 for all sky, with no

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Dominique Bouniol, Fleur Couvreux, Pierre-Honoré Kamsu-Tamo, Madeleine Leplay, Françoise Guichard, Florence Favot, and Ewan J. O’Connor

, the surface temperature and the rate of evapotranspiration, with important consequences on atmosphere–surface interactions and the global hydrological cycle. Cloud radiative forcing at the surface is defined as the difference between surface downward flux and clear-sky surface downward flux ( Ramanathan et al. 1989 ). In this section the radiative forcing of the various cloud categories on shortwave and longwave fluxes at the surface is investigated. a. Cloud radiative impact in the shortwave The

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Qing Yue, Brian H. Kahn, Eric J. Fetzer, Mathias Schreier, Sun Wong, Xiuhong Chen, and Xianglei Huang

; Pincus et al. 2012 ). Therefore, active research efforts have been dedicated to analyzing and understanding the cloud feedbacks and their relationships with different cloud types from both observations and climate models ( IPCC 2013 ). Typically, the cloud feedback is quantified as the change in the cloud radiative forcing (CRF) per unit change in the global mean surface air temperature (in W m −2 K −1 ) after accounting for and removing the effect of clear-sky change on the total CRF change (cloud

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Graeme L. Stephens and Peter J. Webster

1542~rOURNAL OF THE ATMOSPHERIC SCIENCESVOLUME 36Sensitivity of Radiative Forcing to Variable Cloud and Moisture GRAEME L. STEPHENS AND PETER J. WEBSTERCSIRO Division of Atmospheric Physics, Station Street, Aspendale, Victoria, Australia 3195(Manuscript received 1 November 1978, in final form 27 March 1979) ABSTRACT The influence of cloud and moisture distribution on the radiative forcing of the atmosphere is investigated.' A simple radiative transfer model is

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Piotr K. Smolarkiewicz, Roy M. Rasmussen, and Terry L. Clark

JOURNAL OF THE ATMOSPHERIC SCIENCES VOL45, NO. 13On the Dynamics of Haw 'arian Cloud Bands: Island Forcing PIOTR K. SMOLARKIEWICZNational Center for Atmospheric Research,* Boulder, Colorado ROY M. RASMUSSENBureau of Reclamation. Denver, Colorado TERRY L. CLARKNational Center for ,dtmospheric ResearCh, Boulder, Colorado(Manuscript received 9 June 1987, in final form 17 November 1987)ABSTRACT This sl ady focuses on

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Chen Zhou, Mark D. Zelinka, Andrew E. Dessler, and Ping Yang

radiative forcing ( Soden et al. 2008 ; Shell et al. 2008 ). Thus, the CERES cloud feedback is derived not just from different data, but from an entirely different method, so the comparison provides an important test of the MODIS results. The MODIS SW cloud feedback is 0.16–0.28 W m −2 K −1 larger than the CERES SW cloud feedbacks, which is a relatively small difference considering the uncertainty. We therefore consider these quantities to be in good agreement. The MODIS LW cloud feedback is ~0.9 W m

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Yizhe Peggy Bu, Robert G. Fovell, and Kristen L. Corbosiero

differ with respect to the amounts and relative distributions of hydrometeors, such as cloud ice, snow, cloud droplets, etc. ( Fovell et al. 2010b ). These particles have different effective sizes that determine how they interact with longwave (LW) and shortwave (SW) radiation (e.g., Dudhia 1989 ). Herein, we demonstrate how and why cloud–radiative forcing (CRF), the modulation of atmospheric radiation owing to hydrometeors, can influence tropical cyclones. The specific focus is on storm structure

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Jie Peng, Zhanqing Li, Hua Zhang, Jianjun Liu, and Maureen Cribb

, which would decrease maximum wind speeds. This was supported by observations of how variations in aerosols accounted for an 8% variation in the intensity of Atlantic hurricanes ( Rosenfeld et al. 2011 ). Wang et al. (2014) have also shown that both precipitation and net cloud radiative forcing (CRF) over the northwestern Pacific are enhanced by Asian pollution via the invigoration of winter cyclones. A review of aerosol effects on the intensity and microphysics of tropical cyclones has been given

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Meghan F. Cronin, Nicholas A. Bond, Christopher W. Fairall, and Robert A. Weller

1. Introduction Clouds have both a cooling and warming effect on the earth's surface. Because clouds reflect solar radiation back to space, shortwave (solar) cloud forcing acts as a cooling effect, a reduction in the solar radiation that warms the earth's surface. But clouds also have a warming effect through their emission of longwave infrared (terrestrial) radiation, thereby increasing downwelling longwave radiation at the earth's surface. The relative amount of surface warming and cooling by

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Wei-Chyung Wang, Wei Gong, Wen-Shung Kau, Cheng-Ta Chen, Huang-Hsiung Hsu, and Chia-Hsiu Tu

, and the comparison with heating caused by convection and large-scale condensation. Here, as a first step, we use observations to illustrate the spatial and temporal patterns of cloud radiative forcing (CRF), which is related to perturbations of the clear-sky radiation flux due to the presence of clouds ( Potter et al. 1993 and references therein). Two terms, the SW CRF and LW CRF, are usually derived at either the top of the atmosphere (TOA) or at the surface. There have been many studies of CRF

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