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M. Hess, P. Koepke, and I. Schult

The software package OPAC (Optical Properties of Aerosols and Clouds) is described. It easily provides optical properties in the solar and terrestrial spectral range of atmospheric particulate matter. Microphysical and optical properties of six water clouds, three ice clouds, and 10 aerosol components, which are considered as typical cases, are stored as ASCII files. The optical properties are the extinction, scattering, and absorption coefficients, the single scattering albedo, the asymmetry parameter, and the phase function. They are calculated on the basis of the microphysical data (size distribution and spectral refractive index) under the assumption of spherical particles in case of aerosols and cloud droplets and assuming hexagonal columns in case of cirrus clouds. Data are given for up to 61 wavelengths between 0.25 and 40 μm and up to eight values of the relative humidity. The software package also allows calculation of derived optical properties like mass extinction coefficients and Ångström coefficients.

Real aerosol in the atmosphere always is a mixture of different components. Thus, in OPAC it is made possible to get optical properties of any mixtures of the basic components and to calculate optical depths on the base of exponential aerosol height profiles. Typical mixtures of aerosol components as well as typical height profiles are proposed as default values, but mixtures and profiles for the description of individual cases may also be achieved simply.

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Z. Q. Li, H. Xu, K. T. Li, D. H. Li, Y. S. Xie, L. Li, Y. Zhang, X. F. Gu, W. Zhao, Q. J. Tian, R. R. Deng, X. L. Su, B. Huang, Y. L. Qiao, W. Y. Cui, Y. Hu, C. L. Gong, Y. Q. Wang, X. F. Wang, J. P. Wang, W. B. Du, Z. Q. Pan, Z. Z. Li, and D. Bu

, chemical, and radiative properties. The Sun–Sky Radiometer Observation Network (SONET; www.sonet.ac.cn ) is a ground-based Cimel radiometer network with the extension of multiwavelength polarization measurement capability to provide long-term columnar atmospheric aerosol properties over China. In this paper, an overview of SONET infrastructure and data products is briefly introduced and then a climatology study is presented, focusing on aerosol optical, physical, chemical, and radiative properties

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J. A. Coakley Jr. and G. W. Grams

developed to assess the impact of stratospheric aerosolson the global climate through their effect on the equilibrium global mean surface temperature. With theassumptions that the radiation in the atmosphere can be treated as diffuse radiation and that the effect ofthe gases in the stratosphere can be approximated by equivalent gray absorbers and scatterers, an analyticexpression which depends only on the optical properties of the aerosol and the planetary albedo is derivedfor the fractional change in

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Glenn E. Shaw

862 JOURNAL OF THE ATMOSPHERIC SCIENCES VO~-UME36Aerosols at Mauna Loa: Optical Properties GLENN E. SHAWGeophysical Institu!e, University of Alaska, Fairbanks 99701(Manuscript received 19 October 1978, in final form 10 January 1979)ABSTRACT The spectral attenuation of sunlight passing through the atmosphere was determined with the Langleymethod for 110 clear days and at 11 wavelengths to an accuracy

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R. M. Schotland and J. D. Copp

M^v 1982 NOTES 735 Optical Properties of a Plastic Pyranometer Head R. M. SCHOTLANO AND J. D. CoPP Institute of ~4tmospheric Physics. University of Arizona. Tucson 85721 21 September 1981 and 18 January 1982 ABSTRACT The optical characteristics of a newly designed two-step pyranomcter head are described. The head issuitable for use in the spectral

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Tetsu Sakai, Narihiro Orikasa, Tomohiro Nagai, Masataka Murakami, Kenichi Kusunoki, Kazumasa Mori, Akihiro Hashimoto, Takatsugu Matsumura, and Takashi Shibata

, number concentration, orientation, and the optical properties. Lidar is a useful tool for measuring the vertical distribution of the optical properties of cirrus clouds. However, the applications of the lidar measurement to the cirrus cloud studies are rather limited partly due to the lack of knowledge pertaining to the relation between the derived optical properties and the microphysical properties. Several measurement studies compared the lidar-derived optical properties with the in situ cloud

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Robert M. Rauber, Guangyu Zhao, Larry Di Girolamo, and Marilé Colón-Robles

1. Introduction Space-based estimation of the direct shortwave radiative aerosol effect and forcing on the climate system (e.g., Loeb and Kato 2002 ; Sekiguchi et al. 2003 ; Loeb and Manalo-Smith 2005 ; Remer and Kaufman 2006 ) depends on accurate retrieval of aerosol optical properties from remote sensors. Determination of aerosol optical properties is normally limited to clear-air regions, with cloud-masking algorithms (e.g., Higurashi and Nakajima 1999 ; Martins et al. 2002

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David R. Reidmiller, Peter V. Hobbs, and Ralph Kahn

aircraft. Here, we discuss only the in situ measurements collected by the Convair-580 and the remotely sensed MISR aerosol retrievals. The objectives of this paper are: 1) to provide a general characterization of the optical properties and size distributions of the aerosol sampled during CLAMS. 2) To analyze small-scale horizontal variability in particle light scattering coefficient ( σ sp ), particle light absorption coefficient ( σ ap ), single-scattering albedo ( ω 0 ), accumulation, and coarse mode

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Fu-Lung Chang and Zhanqing Li

rather than cooling, as other types of clouds do ( Ramaswamy and Ramanathan 1989 ; Hartmann et al. 1992 ). The horizontal coverage of cirrus clouds and their vertical distribution in the upper atmosphere are also linked to atmospheric circulation and the water cycle ( Stephens et al. 1990 ). To gain a better understanding of the earth’s radiation budget and to improve weather and climate modeling, it is essential to accurately identify these cirrus clouds and determine their optical properties

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Bingqi Yi, Ping Yang, Bryan A. Baum, Tristan L'Ecuyer, Lazaros Oreopoulos, Eli J. Mlawer, Andrew J. Heymsfield, and Kuo-Nan Liou

; Lee et al. 2009 ; Baran 2012 ; and references therein). However, owing to various uncertainties, ice clouds still remain one of the least known components in the atmospheric system. The uncertainties are caused by many factors, from microphysical properties, such as the range of particle size distributions (PSD) with their associated crystal shapes (habits), to optical properties such as extinction coefficient, phase matrix, single-scattering albedo, and asymmetry factor. Modeling studies by

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