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Tianle Yuan and Zhanqing Li

the cloud phase is ice. Cloud phase is extremely important as water and ice hydrometeors have completely different optical properties ( Platnick et al. 2003 ). Treating water clouds as ice clouds, or vice versa, will inevitably lead to errors in the retrievals, which need to be avoided for our purpose. b. DCC definition There is no precise definition of a deep convective cloud using just passive remote sensing measurements. In practice, BT has been used to define DCC by setting a threshold of low

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Oleg Dubovik, Brent Holben, Thomas F. Eck, Alexander Smirnov, Yoram J. Kaufman, Michael D. King, Didier Tanré, and Ilya Slutsker

1. Introduction The lack of detailed knowledge of the optical properties of aerosols results in aerosol being one of the largest uncertainties in climate forcing assessments (cf. Charlson et al. 1992 ; Houghton et al. 1996 ; Tegen et al. 1996 ; Hansen et al. 1997, 2000 ; Heintzenberg et al. 1997 ). Monitoring of atmospheric aerosol is a fundamentally difficult problem. First, compared to atmospheric gases, aerosol is highly inhomogeneous and variable; that is, aerosol observations have to

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Min-Jeong Kim, Mark S. Kulie, Chris O’Dell, and Ralf Bennartz

paper we present a new, purely physical approach to simulate ice-particle scattering at microwave frequencies. The approach we take incorporates both realistic size distributions for the ice particles above the melting layer and scattering parameters that account for their nonspherical particle shape. In a manner similar to BP2001 , we calculate passive microwave optical properties from observed radar reflectivity data and compare forward-simulated brightness temperatures with observed data both

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Judith A. Curry and Elizabeth E. Ebert

CURRY AND EBERT1267NOVEMBER 1992Annual Cycle of Radiation Fluxes over the Arctic Ocean:Sensitivity to Cloud Optical PropertiesJUDITH A. CURRYProgram in Atmospheric and Oceanic Sciences and Aerospace Engineering Sciences, University of Colorado, Boulder, ColoradoELIZABETH E. EBERTBureau of Meteorology Research Centre, Melbourne, Australia(Manuscript received 10 June 1991, in final form 21 January 1992)ABSTRACTThe relationship between cloud optical properties and the radiative fluxes over the

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E. P. Nowottnick, P. R. Colarco, S. A. Braun, D. O. Barahona, A. da Silva, D. L. Hlavka, M. J. McGill, and J. R. Spackman

been implemented within GEOS-5 ( Barahona et al. 2014 ). Additionally, we explore the sensitivity of Nadine to dust absorption by varying the assumed dust optical properties in the simulations that permit aerosol–radiation interaction and both aerosol–radiation and aerosol–cloud interaction in order to explore the sensitivity of Nadine to dust absorption. This work is novel in that it presents global high-resolution simulations of a tropical system with various considerations for how dust is

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S. K. Satheesh and J. Srinivasan

In comments on the paper by Satheesh and J. Srinivasan (2006 , hereafter SS06 ), Ramachandran (2008 , hereafter R08 ) states that “However, the same methodology has been published by Ramachandran and Jayaraman (2003) .” We would like to state that this assertion is completely wrong. Ramachandran and Jayaraman (2003 , hereafter RJ03 ) used the software package Optical Properties of Aerosols and Clouds (OPAC; Hess et al. 1998 ) to derive the aerosol optical depths (by varying the number

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S. Ramachandran

details given in the first few pages of SS06 , including Eqs. (1)–(6), are well known. The calculation of aerosol optical depths (AODs) from the extinction (scattering + absorption) is done using the well-known Beer–Lambert’s law and Mie theory. Information on different properties and refractive indices of aerosols given in Tables 1–3 of SS06 are taken from Hess et al. (1998) , as well as the information required to plot Fig. 1 of SS06 . It is well known that a given change in any individual

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R. Pedrós, J.L. Gómez-Amo, C.R. Marcos, M.P. Utrillas, S. Gandía, F. Tena, and J.A. Martinez Lozano

the lower part of the stratosphere. On the other hand, aerosols experience physical and chemical transformations in the time they spend in the atmosphere, known as aging, which modifies their optical properties. In particular, aerosols change their mixing state as they age. Aerosols can be externally mixed, which means that different aerosol components exist separately. In other words, there is no physical or chemical interaction between the aerosol components. Alternatively, aerosols can be

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Zev Levin, Joachim H. Joseph, and Yuri Mekler

882 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME37Properties of Sharav (Khamsin) Dust mComparison of Optical and Direct Sampling Data ZEV LEVIN, JOACHIM H. JOSEPH AND -URI MEKLERDepartment of Geophysics and Planetary Sciences, Tel Aviv University, Ramat Aviv, Israel(Manuscript received 27 August 1979, in final form 3 December 1979)ABSTRACT Simultaneous measurements of optical depth and

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Fu-Lung Chang and Zhanqing Li

1. Introduction To date, the overlap of high cirrus cloud and low water cloud has posed a major challenge in determining cloud optical properties using passive weather satellite observations. Presence of cirrus overlapping low cloud has been frequently reported by surface observers and aircraft observations ( Hahn et al. 1982 , 1984 ; Warren et al. 1985 ; Tian and Curry 1989 ). Based on a 12-yr (1965–76) dataset of ship-reported synoptic observations over the North Atlantic Ocean between 30

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