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Joseph Sedlar, Matthew D. Shupe, and Michael Tjernström

( Herman and Goody 1976 ; Intrieri et al. 2002b ; Shupe 2011 ), and liquid water content in these clouds tends to have a maximum near cloud top (e.g., Tsay and Jayaweera 1984 ). Therefore, cloud tops protruding into the temperature inversion may have a significant effect on the cloud microphysical composition, lifetime, and the radiative forcing, as well as the thermodynamic structure itself. Curry (1983) modeled the significance of cloud condensate within a temperature inversion for the

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Yi Huang

feedback refers to a physical quantity X other than forcing that influences R , and the strength of the feedback Δ R X can be assessed by the partial contribution of this factor to the change in R . The kernel method ( Soden et al. 2008 ; Shell et al. 2008 ) is a widely used method for analyzing feedback strength. In this method, a noncloud feedback is approximated by multiplying a precalculated first-order sensitivity kernel and a climate response Δ X : The cloud feedback can then be assessed

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Yinghui Liu, Jeffrey R. Key, Steve Vavrus, and Cian Woods

on these 50 events, a subset of all moisture intrusions that have a basinwide impact on the surface DLR. Composite analyses of the following variables were performed: all-sky DLR, clear-sky DLR, longwave cloud radiative forcing (CRF), cloud amount, air temperature at 2 m and 850 hPa, total column water vapor, cloud ice water content, cloud liquid water content, low troposphere stability, geopotential height at 850 and 500 hPa from ERA-Interim, total cloud amount from MODIS, cloud amount from 2B

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S. J. Ghan, X. Liu, R. C. Easter, R. Zaveri, P. J. Rasch, J.-H. Yoon, and B. Eaton

. But Ghan and Easter (2006) showed that for the purpose of characterizing aerosol radiative forcing it is sufficient to distinguish between interstitial aerosol and particles attached to cloud droplets, without treating transport of cloudborne particles. Given a representation of the aerosol size distribution, mixing state, attachment state, composition, and internal structure, the next question is which processes in the aerosol life cycle need to be represented to accurately simulate the

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Masakazu Yoshimori, Julia C. Hargreaves, James D. Annan, Tokuta Yokohata, and Ayako Abe-Ouchi

show smaller sensitivity to the LGM forcing than to the 2 × CO 2 forcing while one model shows the opposite. This asymmetry and model difference are both attributed to the shortwave cloud feedback. Hargreaves et al. (2007) showed that 80% of their PPE members exhibited weaker sensitivity to lowered GHG level than to elevated GHG level. In their study, however, the processes behind this asymmetry were not investigated. Y09 , on the other hand, rigorously investigated feedbacks in both LGM and 2

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Joonsuk Lee, Ping Yang, Andrew E. Dessler, Bo-Cai Gao, and Steven Platnick

convective blowoff, whereas the other half were associated with in situ formation. Because of the high frequency of occurrence of thin cirrus clouds, the effect of these clouds on the earth’s radiation budget can be significant. For example, these clouds, located high in the atmosphere, absorb longwave radiation but emit radiation at very low temperatures, producing local heating by a few degrees per day ( Jensen et al. 1996 ; McFarquhar et al. 2000 ) and net positive cloud radiative forcing on the

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Bryan C. Weare

JULY 1995 WEARE 1889Factors Controlling ERBE Longwave Clear Sky and Cloud Forcing Fluxes BRYAN C. WEAREAtmospheric Science Program, University of California at Davis, Davis, California(Manuscript received 23 May 1994, in final form 6 February 1995) ABSTRACT The factors controlling the Earth Radiation Budget satellite (ERBS) longwave clear sky and

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Howard W. Barker

1. Introduction Twomey (1974 , 1977) has discussed how altering the number of cloud condensation nuclei (CCN) could change cloud albedo thereby affecting an external forcing of Earth’s climate. Basically, as aerosol number concentrations increase via mounting anthropogenic pollution, cloud water is distributed among more CCN thus reducing mean cloud droplet size and enhancing albedo. The Twomey effect, as it has come to be known, received relatively little attention until Charlson et al

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Jonathan Gregory and Mark Webb

“direct” effect is instantaneous. Aerosols in the atmosphere also alter the occurrence and optical properties of clouds, which in turn have an “indirect” radiative effect, but these changes are not instantaneous. Special treatments have been developed for these and other cases to include in F those effects which are considered to be part of the forcing. This is done partly because the resulting values for F are more nearly model independent and hence useful for comparative studies of the climatic

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David B. Mechem, Yefim L. Kogan, Mikhail Ovtchinnikov, Anthony B. Davis, K. Franklin Evans, and Robert G. Ellingson

arising from MD effects may also influence convective dynamics. Instead of these predominantly indirect influences of MD radiative transfer (MDRT) on cloud dynamics, we are concerned with identifying direct impacts of MD effects on the cloud dynamics themselves. As such, we choose to focus on cloud types for which radiative forcing contributes significantly to the system energetics. For boundary layer stratocumulus, cloud top longwave radiational cooling is most frequently the primary engine driving

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