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Oreste Reale, K. M. Lau, and Arlindo da Silva

550 nm, and (bottom) the observed MODIS optical depth at 1200 UTC 13 Sep 2006. Fig . 11. (top) The 108-h forecast (initialized at 0000 UTC 10 Sep 2006) of the extinction optical thickness computed from the GEOS-5 at 550 nm, and (bottom) the observed MODIS optical depth at 1200 UTC 14 Sep 2006. Figure 12 shows an 84-h forecast of zonal wind and temperature for the location of the Cape Verde vertical sounding, validated against the actual observations taken during SOP-3. The impact of the aerosol

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Jörg Bendix, Boris Thies, Jan Cermak, and Thomas Nauß

microphysical properties is performed [liquid water path (LWP), effective radius]. This step is required for the determination of the geometrical thickness (step 3) of a cloud layer by specific approaches. Various algorithms for the retrieval of optical and microphysical properties based on NOAA AVHRR data have been successfully used in the past (e.g., Bendix 1995a ; Nakajima and Nakajima 1995 ; Bendix 2002 ) and have recently been adapted to the MODIS instrument ( Platnick et al. 2003 ; Nauß et al

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Ming Liu, Douglas L. Westphal, Annette L. Walker, Teddy R. Holt, Kim A. Richardson, and Steven D. Miller

Prediction System (COAMPS), with an embedded dust aerosol model ( Liu et al. 2003 ), has produced 3-day forecasts for southwest Asia in real-time runs since March 2003. The focus was on the Iraq region including the Arabian Gulf and the nearby areas, providing dust concentration, visibility, and optical depth in support of U.S. Department of Defense military operations. Real-time COAMPS dust forecasting has been carried on since then in a combined research and operational mode. This is the first

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Ming Liu, Jason E. Nachamkin, and Douglas L. Westphal

calculating the optical properties of aerosol species in addition to clouds has become necessary for COAMPS. The standard Harshvardhan radiation package lacks such a capability. In response to these needs, a high-order accurate broadband radiative transfer model was recently implemented into COAMPS. The model details can be found in Liou et al. (1988) and Fu and Liou (1992 , 1993) . The new radiation parameterization or model is named Fu–Liou in the following discussions to distinguish it from the

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Melanie A. Wetzel, Steven K. Chai, Marcin J. Szumowski, William T. Thompson, Tracy Haack, Gabor Vali, and Robert Kelly

a stratus cloud droplet size retrieval method for AVHRR-K/L/M. Remote Sens. Environ , 36 , 105 – 119 . 10.1016/0034-4257(91)90033-3 Wetzel, M. A. , and Stowe L. L. , 1999 : Satellite-observed patterns in stratus microphysics, aerosol optical thickness, and shortwave radiative forcing. J. Geophys. Res , 104 , 31287 – 31299 . 10.1029/1999JD900922 Wetzel, M. A. , Borys R. D. , and Xu L. E. , 1996 : Satellite microphysical retrievals for land-based fog with validation by balloon

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Glenn D. Rolph, Roland R. Draxler, Ariel F. Stein, Albion Taylor, Mark G. Ruminski, Shobha Kondragunta, Jian Zeng, Ho-Chun Huang, Geoffrey Manikin, Jeffery T. McQueen, and Paula M. Davidson

HYSPLIT and HMS plumes. (b) MOEs for the 1, 5, 20, and 100 μ g m −3 analysis (open symbols) and forecast (filled symbols) thresholds for the entire 2007 fire season. Fig . 11. GOES-12 smoke aerosol image depicting aerosol optical thickness at 2245 UTC 17 Aug 2007. The high values seen across the Ohio River valley correspond to smoke originating from fires in ID and MT. Fig . 12. The definitions of forecast ( F ), observed ( O ), and hit ( H ) in the NCEP FVS. Fig . 13. Time series of monthly mean

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Seungkyu K. Hong, Sang-Boom Ryoo, Jinwon Kim, and Sang-Sam Lee

1. Introduction Asian dusts composed of dry sands, clay, and loam, exert great social and economic impacts on East Asia (EA). Severe Asian dust events often lead to canceled flights and adversely affect the manufacturing of semiconductors and precision instruments ( Shao and Dong 2006 ). Increased optical thickness by Asian dusts inhibits photosynthesis, causing plant growth disorders and ecosystem disturbances ( Huang et al. 2006 ; Kim et al. 2005 ). Previous studies also showed that Asian

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Paul J. Croft, Russell L. Pfost, Jeffrey M. Medlin, and G. Alan Johnson

local industry emissions) may have contributed to the fog’s intensity (or optical thickness) by increasing droplet concentrations. Accident victims indicated that the fog appeared as a solid wall with near-zero visibility when they drove into it. Radiative effects, related to sunrise, as well as chemical effects, may have also played a role in the fog’s intensity. b. Sea fog assessment Sea fog and stratus can affect extensive areas of the northern Gulf of Mexico as well as the immediate coastal

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Robert P. d’Entremont, Richard Lynch, Gennadi Uymin, Jean-Luc Moncet, Ryan B. Aschbrenner, Mark Conner, and Gary B. Gustafson

an a priori cloud analysis to exclude their adverse influence on the retrieval of the radiatively important aerosol optical thickness and particle effective size attributes. Cloud screening is also important for earth surface monitoring applications including retrievals of albedo, vegetation health, and land cover change from space. A central paradigm of cloud detection models in the remote sensing community is to compare satellite-observed upwelling radiance signatures to those expected for the

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Christian Herold, Dietrich Althausen, Detlef Müller, Matthias Tesche, Patric Seifert, Ronny Engelmann, Cyrille Flamant, Rohini Bhawar, and Paolo Di Girolamo

scattering, the height-dependent transmission ratio of the atmosphere, , was calculated. For this, an Ångström exponent of 1.5 and an aerosol optical thickness (AOT) of 0.4 were assumed at the wavelength of 396.5 nm for the residual layer with a top height of 2 km above ground level (AGL). Above the residual layer, an AOT of 0.02 was estimated to represent the conditions in the free troposphere. The AOT for the residual layer is twice as much as typical values for measurements during COPS. Figures 1a

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