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Luc R. Bissonnette, Gilles Roy, and Grégoire Tremblay

returns, the range-resolved extinction coefficient and effective particle diameter. From these primary solutions and the assumption that the form of the droplet size distribution is known or given, for example, a modified gamma function for cloud droplets, other important microphysical parameters such as the liquid water content (LWC) of water clouds can be calculated at the same high temporal and spatial resolutions as those of the original lidar measurements. The subject of this paper is not the

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E. Bouzereau, L. Musson-Genon, and B. Carissimo

1. Introduction Early condensation schemes of cloud models contained the assumption that a computational grid box volume element was either entirely saturated or entirely unsaturated. To improve upon this crude approximation, Sommeria and Deardorff (1977) introduced the concept of statistical distribution for variables such as total water specific humidity q w and liquid water potential temperature θ l , allowing the computation of partial cloudiness R and liquid water specific humidity

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Yi Ming and Isaac M. Held

1. Introduction A complicating factor in simulating and understanding the climatic roles of water vapor (WV) and clouds is their tight coupling with circulation, posing a major bottleneck in narrowing the uncertainty of cloud feedback ( Bony et al. 2015 ). This motivates us to construct a model of passive WV and clouds, meaning that both are advected as tracers that do not feed back on circulation either through latent heat release or through cloud radiative effects (CRE). Such a model can be

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Lawrence D. Carey, Jianguo Niu, Ping Yang, J. Adam Kankiewicz, Vincent E. Larson, and Thomas H. Vonder Haar

1. Introduction At temperatures between 0° and −40°C, liquid water droplets and ice crystals may coexist in a single-layered cloud. Although studies have indicated that the parameterization of so-called mixed-phase clouds is critical for understanding the radiative characteristics of clouds in climate models and satellite remote sensing applications (e.g., Li and Le Treut 1992 ; Sun and Shine 1995 ; Gregory and Morris 1996 ; Hogan et al. 2002 ; Yang et al. 2003 ; McFarquhar and Cober 2004

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Ruiyue Chen, Fu-Lung Chang, Zhanqing Li, Ralph Ferraro, and Fuzhong Weng

1. Introduction It has long been recognized that clouds play a dominant role in the earth’s climate and its changes. Clouds strongly affect the energy balance and water cycle, two dominant processes in the climate system. Low-level boundary layer clouds have the most significant influence on cloud radiative forcing because of their areal extent and frequency ( Harrison et al. 1990 ; Hartmann et al. 1992 ). Radiation absorbed by boundary layer clouds also plays an important role in the

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Yi Ming, V. Ramaswamy, Leo J. Donner, Vaughan T. J. Phillips, Stephen A. Klein, Paul A. Ginoux, and Larry W. Horowitz

1. Introduction Clouds, which cover a significant fraction of the earth’s surface, play a critical role in affecting the radiation balance by partly reflecting the incoming shortwave sunlight back to space and by absorbing infrared radiation emitted by the surface. As a highly dispersed system made up of tiny droplets, a water cloud can be characterized in terms of liquid water content (LWC) and droplet number concentration ( N d ). The corresponding cloud optical depth ( τ ) is approximately

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John K. Williams and J. Vivekanandan

microphysical quantities such as cloud liquid water content (LWC) and drop size estimates ( Gosset and Sauvageot 1992 ; Vivekanandan et al. 1999a , 2001 , 2004 ; Hogan et al. 2005 ). If effective, this capability would offer the prospect of remotely monitoring cloud microphysical characteristics, providing data useful for understanding meteorological processes, assimilation into numerical weather prediction (NWP) models, validating NWP forecasts and satellite-based retrievals, identifying conditions

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Matthew D. Lebsock, Tristan S. L’Ecuyer, and Graeme L. Stephens

convection ( Stevens et al. 2005 ; Wood et al. 2008 ) in drizzling stratocumulus, even modest precipitation rates can affect the mesoscale organization of warm clouds ( Wang and Feingold 2009 ) and thus influence key macrophysical quantities such as cloud fraction and cloud liquid water path that govern the radiative effects of these clouds. The sensitive nature of the relationship between precipitation and low cloud cover contributes to uncertainty in anthropogenic modifications of the earth’s climate

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Salvador Matamoros, Josep-Abel González, and Josep Calbó

determination of these properties is usually based either on measurements (from satellites or airplanes) of reflected radiation within the visible or the near-infrared bands, or on ground measurements of radiation transmitted through the clouds. The scope of these methods is shown in a review by Clothiaux et al. (2005) . Optically thick water clouds allow the presence of the diffuse component of shortwave radiation but not the direct component. The cloud optical depths of such clouds can be evaluated from

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Christopher W. O’Dell, Frank J. Wentz, and Ralf Bennartz

based on SSM/I also suggest a modest decrease in global surface winds ( Wentz et al. 2007 ). In addition to water vapor and surface wind speed, the SSM/I is also sensitive to column-integrated cloud liquid water path (LWP) and precipitation. Because the low-frequency microwave channels fully penetrate virtually all clouds, they can provide a direct measurement of the total liquid (but not solid) cloud condensate amount, though there is some dependency on the cloud temperature ( Petty 1990 ; Liu and

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