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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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Fu-Lung Chang and James A. Coakley Jr.

1. Introduction Cloud feedback is one of the largest sources of uncertainties in climate sensitivity studies from general circulation models (GCMs; Cubasch et al. 2001 ; Stephens 2005 ). The interaction of radiation with cloud optical properties, in particular, cloud optical depth, can significantly alter the amount of radiative energy flow that enters and leaves the earth’s surface and atmosphere (e.g., Wielicki et al. 1995 , 1996 ; Houghton et al. 1996 ). The strong impact of clouds on

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B-J. Sohn, Seung-Hee Ham, and Ping Yang

properties of these clouds are known. The DCCs that overshoot the tropical tropopause layer (TTL) can be identified on the basis of a criterion specified in terms of infrared brightness temperature, and the characteristic optical properties of the selected DCCs can be determined. Furthermore, the inferred optical property information can be employed to simulate the top-of-atmosphere (TOA) radiances on the basis of state-of-the-art radiative transfer modeling capabilities. If these results are able to

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