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James T. Peterson, Edwin C. Flowers, and John H. Rudisill III

) ABSTRACT Atmospheric turbidity (aerosol optical thickness) was measured with sunphotometers across the LosAngeles Basin. Automobiles were used for east-west traverses of the metropolitan area (a distance of --,100kin) on two days with distinctly different meteorological conditions: a hazy, relatively humid day and awarmer, d~er, less hazy day wi~h easterly Santa Ana wind flow. Additionally, incident global UV and totalsolar irradlance were measured at six sites (five urban and one rural) and

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Larry L. Stowe, Herbert Jacobowitz, George Ohring, Kenneth R. Knapp, and Nicholas R. Nalli

spanning over 19 years from September 1981 to December 1999 (see appendix B for notes on the extent of this dataset). The principal dataset parameters are the channel reflectances (%) and infrared radiances [mW(m 2 cm −1 sr) −1 , total cloud amount (%), components of the earth's radiation budget (ERB, W m −2 )] at the top of the atmosphere (TOA); outgoing longwave radiation (OLR), and absorbed solar radiation by the earth–atmosphere system (ASR), and aerosol optical thickness (AOT) over the oceans

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Thomas A. Jones and Sundar A. Christopher

of particulate matter from space over cloud-free regions ( Chu et al. 2002 ). The aerosol retrieval algorithm over land uses reflectance from three channels (0.47, 0.67, 2.13 μ m) and reports the aerosol optical thickness (AOT) at 0.55 μ m ( Remer et al. 2005 ; Levy et al. 2007 ). The retrieval algorithm works by matching the observed reflectance values to expected values based on radiative transfer model generated lookup tables for various aerosol types. Once a best-fit match is made, the AOT

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R. E. Samuelson

darkening observations of Venus. An inversion of the transfer equation,including both anisotropic multiple scattering and arbitrary thermal emission, is used to obtain informationabout the thermal structure and scattering properties of the Cytherean atmosphere in the region aroundthe tropopanse. The results, when normalized to the thermal profile deduced from the Mariner 5 S-band radio occultationexperiment, imply the following atmospheric properties: I) the 8-14 ~ optical thickness o! the lower

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Greg M. McFarquhar, Andrew J. Heymsfield, James Spinhirne, and Bill Hart

) measurements, and Wang et al. (1994) , using the Stratospheric Aerosol Gas Experiment (SAGE) II measurements, both observed optically thin cirrus near the tropopause more than 50% of the time in warm pool regions. Using ground-based lidar, Uthe and Russell (1977) also established a high frequency of occurrence of subvisible cirrus that typically persisted for several days. More recently, Nee et al. (1998) found subvisible cirrus with average geometrical and optical thicknesses of 0.6 and 0.008 km

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Qingyuan Han, William B. Rossow, Jian Zeng, and Ronald Welch

albedo and droplet radius are positively correlated for most optically thin clouds ( τ < 15) and negatively correlated for most optically thick clouds ( τ > 15), where τ is referred to λ = 0.6 μ m. Such a relationship compares favorably with the behavior exhibited by several GCMs (e.g., Lohmann et al. 1999 ; G01 ). Nevertheless, the estimated aerosol indirect effect (−1.7 W m −2 ) from the Model for Integrated Research on Atmospheric Global Exchanges (MIRAGE) ( G01 ) is much larger than that

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Jinhuan Qiu, Xiangao Xia, Jianghui Bai, Pucai Wang, Xuemei Zong, and Daren Lu

solar radiation measurements. Based on the fact that GSI is weakly sensitive to aerosol optical parameters in the case of aerosol optical thickness (AOT) < 0.2, Qiu et al. (2008) presented a method to estimate the uncertainties of historic GSI data in China. This evaluation method is not completely independent of DSI data quality, so further study on this issue is still required. More specifically, we need a simple yet effective calibration method that, as far as possible, is independent of

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Kirk D. Knobelspiesse, Christophe Pietras, and Giulietta S. Fargion

1. Introduction This note is an extension and validation of the recommendations made in Porter et al. (2001) with regard to problems associated with proper sun pointing using a MICROTOPS II (Solar Light, Inc.) sun photometer. Porter et al. (2001) showed that rough sea conditions can cause a bias in aerosol optical thickness (AOT) measurements with the MICROTOPS II sun photometer when using the manufacturer-supplied default measurement protocol, because this protocol is not sufficient to

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William B. Rossow and Yuanchong Zhang

combined with the whole weather satellite constellation using the ISCCP dataset. As a first step toward this goal, we use an early version of the combined C&C cloud layer profiles to evaluate our previous statistical model of CVS. This study specifically tests the hypothesis that the cloud types defined by top pressure and optical thickness correspond to specific CVS; although originally based on the climatological statistics of cloud layer distributions, we pose the most severe test by matching

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Robert W. Fett and Ronald G. Isaacs

PREDRSCHFAC Tech. Rep. 77-04, Naval Air Systems Command (AIR-370), Dept. of the Navy, Washington, DC, 161 pp.Goody, R. M., 1964: Atmospheric Radiation. Clarendon Press, 436 pp.Griggs, M., 1975: Measurement of atmospheric aerosol optical thickness over water using ERTS-1 data. J. Air Pollut. Control Assoc., 25, 622-626.Hoffer, T. E., and H. H. Johannsen, 1969: Ecological Potential in Spectral Signature Analysis in Remote Sensing in Ecology. UniversiW of Georgia Press, 1-16.Liou, K. N., 1973: A

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