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Robert Paul d'Entremont and Gary B. Gustafson

background fields are not required to provide an accurate estimate of clear-scene counts in an absolute sense but rather the relative changes as a function of time of day. Clear-scene visible reference background fields are generated directly from satellite measurements as a by-product of previous cloud analyses. Changes in the satellite-observed visible background are caused predominantly by variations in bidirectional reflectance properties of the Earth's surface, and are due to changes in solar

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Izaya Numata, Mark A. Cochrane, and Lênio S. Galvão

and Souza 1998 ; Souza et al. 2005a ; Souza et al. 2005b ; Matricardi et al. 2010 ). Furthermore, unlike forest conversion to other land-cover types, such as agriculture, subtle changes of disturbed forests in terms of physiology and structure may not be well characterized by multispectral sensors. Hyperspectral sensors, with several spectral bands between 400 and 2400 nm, provide detailed spectral information associated with biochemical and physiological properties of vegetation ( Gamon et al

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R. K. Kaufmann, L. F. Paletta, H. Q. Tian, R. B. Myneni, and R. D. D’Arrigo

atmospheric carbon dioxide, satellite measurements of NDVI, anthropogenic carbon emissions, and aerosol optical depth (AOD) using the notion of Granger causality. Clive Granger was awarded the 2003 Nobel Prize in Economics in part for his statistical notion of causality; nevertheless, we recognize that Granger causality is not equivalent to the meaning of causality in physical sciences. Despite this difference, Granger causality goes well beyond the simple notion correlation ( Granger 1969 ). As such

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Xin-Zhong Liang, Hyun I. Choi, Kenneth E. Kunkel, Yongjiu Dai, Everette Joseph, Julian X. L. Wang, and Praveen Kumar

, the CLM needs soil sand and clay fraction profiles to specify soil properties in individual layers and bedrock depth to set the soil bottom impermeable to water. Meanwhile, all modules use the land-cover category (LCC) to define static canopy (morphological, optical, physiological) properties, which are more comprehensive in the CLM. With regard to these aspects, the CLM approach, albeit more demanding, is physically more appropriate and, fortunately, viable with current data availability. A more

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Allison L. Steiner, Dori Mermelstein, Susan J. Cheng, Tracy E. Twine, and Andrew Oliphant

: Second generation operational algorithm: Retrieval of aerosol properties over land from inversion of Moderate Resolution Imaging Spectroradiometer spectral reflectance . J. Geophys. Res. , 112 , D13211 , doi:10.1029/2006JD007811 . Li , B. , H. Yuan , N. Feng , and S. Tao , 2009 : Comparing MODIS and AERONET aerosol optical depth over China . Int. J. Remote Sens. , 30 , 6519 – 6529 . Liepert , B. , and I. Tegen , 2002 : Multidecadal solar radiation trends in the United States

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Grant L. Harley, James King, and Justin T. Maxwell

-derived increase in aerosol optical depth (AOD) and subsequent reduced total PAR was the mechanism responsible for triggering the production of the IADF in P. elliottii during the peak of the 2010 growing season (July). 2. Materials and methods We analyzed Earth Observation (EO) products available from NASA, surface meteorological measurements, and modeled irradiance data to reveal a relationship between dust-derived changes in AOD and atmospheric conditions at the surface in southern Florida. Tree growth

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Cuizhen Wang, Jiaguo Qi, and Mark Cochrane

canopies and open area. During the dry season in the Amazon grasses and leaf litter in open areas are senescent and have similar spectral properties to soils. Therefore, the green tree canopy and open area have distinct spectral signatures in remotely sensed data. The spectral response of the pixel in logged forests is thus the collective contribution of these two components. The canopy fractional cover is determined by the area of tree canopies in one pixel. Any satellite image with moderate to coarse

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Y. C. Sud, G. K. Walker, V. M. Mehta, and William K-M. Lau

is in the surface hydrology, specifically the influence of the snow/ice process on land ( Mocko and Sud, 2001 ). The other features of the GEOS GCMs are (i) the prognostic fractional cloudiness and cloud optical properties and associated cloud microphysics and (ii) the ability to perform coordinate translation and rotation with a provision for relocating the mathematical poles to any arbitrary location (irrelevant for this investigation). 2.1 Cloud Physics in McRAS Relaxed Arakawa–Schubert Scheme

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L-M. Rebelo, G. B. Senay, and M. P. McCartney

objectives of the research reported in this paper were to investigate and characterize flood pulsing of the Sudd wetland over a 12-month period. The time period chosen for the analysis was June 2007–May 2008 because of the availability of remote sensing data. Analyses of radar and optical remote sensing datasets are presented here to determine the spatial and temporal patterns of inundation within the Sudd and evaporation rates from the wetland during the 12-month period. 2. Characteristics of the Sudd

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M. Rodell, B. F. Chao, A. Y. Au, J. S. Kimball, and K. C. McDonald

cycles in agricultural land, and the seasonal growth and disappearance of opportunistic plants in the Arctic. It also undergoes interannual variations dependent upon land use and climate variability. Temporal variations of biomass distribution were computed and are presented below for 17 yr from which consistent satellite observations of vegetation properties are available. The resultant global geodynamic effects were quantified and compared against geodetic observations, for both seasonal and

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