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Jinwon Kim, Yu Gu, and K. N. Liou

. 2003 ), these uncertainties are not expected to influence our study critically considering that we focus on providing qualitative information by prescribing a simple aerosol optical thickness (AOT) value. In our judgment, the OPAC database is so far the best data source for determining the single-scattering properties of spherical aerosols for broadband radiative flux calculations. The single-scattering albedo inferred from remote sensing data can be used to calibrate the existing database once

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X. Pedruzo-Bagazgoitia, H. G. Ouwersloot, M. Sikma, C. C. van Heerwaarden, C. M. J. Jacobs, and J. Vilà-Guerau de Arellano

( Wang et al. 2008 ; Oliveira et al. 2011 ). Similar to aerosols, clouds also influence the partitioning between direct and diffuse radiation. However, the optical thickness of clouds can be larger than that for aerosols. Thick clouds absorb most direct radiation ( Min 2005 ), and little diffuse radiation reaches the surface. Below optically thin clouds the reduction in direct radiation can be significant but limited, and diffuse radiation is greatly enhanced ( Cheng et al. 2016 ). We here follow

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S. O. Los, N. H. Pollack, M. T. Parris, G. J. Collatz, C. J. Tucker, P. J. Sellers, C. M. Malmström, R. S. DeFries, L. Bounoua, and D. A. Dazlich

high average NDVI values exhibit low interannual variation ( section 5 ), and it is assumed therefore that the deviations in NDVI data from these areas were caused by the El Chichón aerosols. The threshold value of NDVI greater than 0.5 was selected as a compromise to select green invariant targets and to obtain sufficient spatial and temporal coverage. Top-of-the-atmosphere reflectance in individual channels increases exponentially with increasing optical thickness. Nonlinear regression ( Bates

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John M. Forsythe, Jason B. Dodson, Philip T. Partain, Stanley Q. Kidder, and Thomas H. Vonder Haar

predict TPW. Rossow et al. (2005) and Rossow and Zhang (2010) used optical thickness and cloud-top pressure from the International Satellite Cloud Climatology Project (ISCCP) to estimate cloud vertical distributions and structure, and compared the predictions to CloudSat / Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations ( CALIPSO ) mission cloud vertical occurrence profiles. No information on water vapor was used. Rossow and Zhang (2010) point out the important distinction

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Jongyoun Kim and Terri S. Hogue

clear-sky conditions using the following relationship: where and PET i are daily and instantaneous potential evapotranspiration, respectively. 3) Estimating daily PET for all-sky conditions We use the following assumptions to develop a “cloudy day” PET estimate: 1) a simple interpolation between adjacent clear days can be used to derive theoretical clear-day shortwave and net radiation values on cloudy days, and 2) the observed cloud fraction and optical thickness are two primary

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Rosie Howard and Roland Stull

:// .] Warren, S. G. , 1982 : Optical properties of snow . Rev. Geophys. , 20 , 67 –89 , doi: 10.1029/RG020i001p00067 . Warren, S. G. , and Wiscombe W. J. , 1980 : A model for the spectral albedo of snow. II: Snow containing atmospheric aerosols . J. Atmos. Sci. , 37 , 2734 – 2745 , doi: 10.1175/1520-0469(1980)037<2734:AMFTSA>2.0.CO;2 .

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R. A. Roebeling, E. L. A. Wolters, J. F. Meirink, and H. Leijnse

-resolution channel and 3 × 3 km 2 for the other channels. Over northern Europe (the Netherlands) the satellite viewing zenith angle of SEVIRI is about 60° and, as a consequence, the spatial resolution is reduced to about 4 × 7 km 2 . b. Satellite retrievals The cloud physical properties (CPP) algorithm of the Satellite Application Facility on Climate Monitoring (CM-SAF) is used to retrieve cloud phase (CPH), cloud optical thickness (COT), cloud particle size ( r e ), and condensed water path (CWP) from SEVIRI

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Marlon Maranan, Andreas H. Fink, Peter Knippertz, Leonard K. Amekudzi, Winifred A. Atiah, and Martin Stengel

al. 2017 ). CLAAS-2 is compiled by the Satellite Application Facility on Climate Monitoring (CM SAF), which processes data from the multichannel Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board the Meteosat satellite with a spatiotemporal resolution of 3 km (at nadir) and 15 min, respectively ( Aminou 2002 ). We make particular use of three quantities: 1) the cloud optical thickness (COT) in the visible spectrum, increasing with stronger scattering by water droplets and ice

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B. A. Forman and S. A. Margulis

multiscale processes and flow-dependent behavior in clear-sky versus cloudy-sky fluxes. Over large areas of space, radiative fluxes are often found in both clear-sky and cloudy-sky regions. Differences between clear- and cloudy-sky conditions can introduce differences in the scales of the processes affecting downwelling radiative fluxes. Similarly, scale differences within a cloud system (e.g., regions of low optical thickness adjacent to regions of high optical thickness) can often introduce multiscale

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M. Susan Moran, Bradley Doorn, Vanessa Escobar, and Molly E. Brown

, AMSR, and SMOS observations differ from SMAP products in spatial resolution, surface penetration, accuracy, and processing, they have been useful for SMAP applied research. The Masdar Institute study of dust emission in the Middle East showed that as SMOS observations of soil moisture increased, the aerosol optical thickness decreased to a threshold moisture content above which no dust emission took place. Agriculture and Agri-Food Canada (AAFC) is developing a system to integrate multisensor soil

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