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Cheng Dang, Qiang Fu, and Stephen G. Warren

−1 ). The accuracy of ice optical properties obtained by using such effective spheres is critical when performing the snow albedo calculation. Beginning in the 1990s, a series of papers was published to evaluate the equal-volume-to-area representation for different shapes of ice crystals in clouds and snow, including circular cylinders ( Grenfell and Warren 1999 ), hexagonal prisms ( Fu et al. 1999 ; Neshyba et al. 2003 ), and hollow prisms ( Grenfell et al. 2005 ). These studies show that the

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Kenneth J. Voss, Scott McLean, Marlon Lewis, Carol Johnson, Stephanie Flora, Michael Feinholz, Mark Yarbrough, Charles Trees, Mike Twardowski, and Dennis Clark

area of very uniform oceanic optical properties, along with a simple, preferably clean, cloud-free atmosphere. The two major instrumented sites for this effort to date have been the Marine Optical Buoy (MOBY) site off Lanai, Hawaii ( Clark et al. 2003 ), and the BOUSSOLE (Bouée pour L’acquisition de Séries Optiques à Long Terme) site for European satellites, in the Mediterranean offshore from Nice, France ( Antoine et al. 2008 ). These continuous data sites are useful, as they can provide the

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Kentaroh Suzuki, Teruyuki Nakajima, Takashi Y. Nakajima, and Alexander P. Khain

1. Introduction The climatic effects of warm clouds are characterized by their optical and microphysical properties, which are represented by parameters such as cloud droplet effective radius (CDR) and cloud optical thickness (COT). These two cloud parameters have been observed by remote sensing technique from aircraft (e.g., Nakajima et al. 1991 ; Asano et al. 1995 ; Brenguier et al. 2000 ) and satellite (e.g., Han et al. 1994 ; Nakajima and Nakajima 1995 ; Kawamoto et al. 2001 ), and

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R. A. Hansell, S. C. Tsay, Q. Ji, N. C. Hsu, M. J. Jeong, S. H. Wang, J. S. Reid, K. N. Liou, and S. C. Ou

the field. In addition, the limited experimental data on dust optical properties at infrared wavelengths and the large uncertainties in the spatially and temporally dependent particle properties—size, shape, and composition ( Sokolik and Toon 1999 )—have indeed made it a difficult challenge to constrain the LW impact. The term “aerosol radiative forcing” is now commonly used for gauging changes in the radiative fluxes due to anthropogenic aerosols since the beginning of the industrial era (∼1750

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B. L. Zhuang, S. Li, T. J. Wang, J. Liu, H. M. Chen, P. L. Chen, M. M. Li, and M. Xie

.20% in NC, approximately 3 times that in SC. There have been many modeling and observational studies on the optical properties and direct radiative forcing from the total BC emissions over East Asia. Wu et al. (2008) , Zhuang et al. (2013) , and K. Li et al. (2016) showed that the annual mean BC DRF at the TOA is approximately +0.32, +0.81 and +1.46 W m −2 in all-sky conditions, as derived from different emission inventories (1.01, 1.81, and 1.84 Tg yr −1 , respectively) over East Asia (100

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Theodore W. Letcher, Sandra L. LeGrand, and Christopher Polashenski

incorporation of an explicit sublimation term which may limit this model’s accuracy under certain atmospheric conditions as sublimation will modify both the blowing snow mass concentration and optical properties. Finally, as part of this case study, we neglected to address the snow surface erodibility and u * t parameter in a physically meaningful way by treating it as uniform in time and space. While we argue that such a representation is acceptable for this case study due to the fact that the snow

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Tiangang Yuan, Siyu Chen, Jianping Huang, Dongyou Wu, Hui Lu, Guolong Zhang, Xiaojun Ma, Ziqi Chen, Yuan Luo, and Xiaohui Ma

aerosol optical properties over Loess Plateau of northwestern China . J. Quant. Spectrosc. Radiat. Transfer , 112 , 346 – 360 , . 10.1016/j.jqsrt.2010.09.006 Chen , F. , and J. Dudhia , 2001 : Coupling an advanced land surface–hydrology model with the Penn State–NCAR MM5 modeling system. Part I: Model implementation and sensitivity . Mon. Wea. Rev. , 129 , 569 – 585 ,<0569:CAALSH>2.0.CO;2 . 10

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Andreja Sušnik, Heidi Holder, and William Eichinger

singularity, developing nonphysical values of the extinction coefficient after the sign change at r ≈ 1.5 km. 2. Description of the method Our proposed method for inverting the data minimizes the variance of the inverted lidar signal in some designated region of lidar ranges [ r j , r k ]. We are assuming that the aerosols in this volume of space originate from a single distribution—that is, the size distribution and the distribution of the optical properties of the aerosols are not changing. While

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Eric Tromeur and William B. Rossow

with longitude and season for a given WS since the WS are defined by the cloud optical properties. Moreover, there is a little variation of the net fluxes with WS except for TOA (and in the atmosphere) net LW, which varies with cloud-top height (not shown). Total in-atmosphere SW absorption is nearly the same for all WS because cloud effects are offset by water vapor effects (the exception is WS2, which has a SW absorption about 40 W m −2 smaller that for the others WS in the Indo-Pacific region

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Sungwook Hong and Inchul Shin

is the small-scale roughness, is the wavelength, and θ is the view angle. 3. Data and methods a. Small-scale roughness retrieval In general, calculation of specular reflectivity at a given frequency and incidence angle using the Fresnel equation requires a priori information on the surface. In many cases, the dielectric property of the surface is not known because of the variety, heterogeneity, and complexity of the surface component and physical state. To use the observed polarization

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