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Christopher Potter, Pusheng Zhang, Steven Klooster, Vanessa Genovese, Shashi Shekhar, and Vipin Kumar

represents the gross monthly atmospheric input of water to that basin. A portion of this gross PREC input flux is lost back to the atmosphere within the same month as PET flux, resulting in a net atmospheric input water flux to the basin area, computed as PREC − PET with a minimum monthly value of zero. We computed monthly PET flux from air surface temperature ( New et al., 2000 ) according to the method of Thornthwaite ( Thornthwaite, 1948 ), as documented in Potter and Klooster ( Potter and Klooster

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A. J. Pitman and S. E. Perkins

-holding capacity of the atmosphere by about 7% K −1 ( Trenberth 1998 ). Soden et al. ( Soden et al. 2002 ) indicate that models suggest that changes in relative humidity are small, hence the actual moisture content of the atmosphere should increase by roughly 7% K −1 ( Trenberth et al. 2003 ). However, because of the nonlinear dependence of moisture with temperature, the largest absolute increase in moisture would be expected in the tropics. Trenberth et al. ( Trenberth et al. 2003 ) use this insight

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Scott R. Loarie, David B. Lobell, Gregory P. Asner, and Christopher B. Field

water increased albedo from 12.1% to 15.8% from increased NIR and MIR reflectance in the middle part of the year ( Figure 3 ). To quantify the relationship between surface water and albedo in the Buenos Aires region of Argentina (supplementary Figure S6), we identified the extent of surface water using the fifth band of a 30-m Landsat image (path 227, row 84, 25 January 2006) that covered 38 630 1-km MODIS kernels. Albedo was well correlated with surface water ( R 2 = 0.34) and varied from 19.4% to

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Gretchen Keppel-Aleks, Samantha J. Basile, and Forrest M. Hoffman

metric and to the emergent constraint. For example, Cox et al. (2013) spatially integrated global land fluxes to represent the variation in atmospheric , implicitly assuming the atmosphere is instantaneously well mixed. In reality, atmospheric varies with location due to atmospheric transport patterns and is sampled only at discrete points in space and time. The estimated from atmospheric therefore depends on the extent of spatial and temporal averaging of the observations ( Keppel-Aleks et

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Jingfeng Xiao, Qianlai Zhuang, Eryuan Liang, Xuemei Shao, A. David McGuire, Aaron Moody, David W. Kicklighter, and Jerry M. Melillo

droughts on tree growth and ecosystem carbon uptake in the north and northwest. Modeling of drought impacts on terrestrial carbon cycling Model description We used a process-based biogeochemical model, the TEM ( Raich et al. 1991 ; Melillo et al. 1993 ; McGuire et al. 2001 ; Zhuang et al. 2003 ), to estimate drought effects on ecosystem carbon fluxes. TEM is a global biogeochemistry model that simulates the cycling of carbon, nitrogen, and water among vegetation, soils, and the atmosphere at monthly

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A. H. M. Siddique-E-Akbor, Faisal Hossain, Safat Sikder, C. K. Shum, Steven Tseng, Yuchan Yi, F. J. Turk, and Ashutosh Limaye

( Figure 2 ). The Himalayas are comprised of more than a hundred mountains exceeding 7200 m in height. Elevations of the Vindhya Range are from 450 to 1100 m. Figure 2. (top) Topographic map of GBM basin derived from SRTM elevation data, (middle) stream network of GBM basins derived from SRTM DEM data, and (bottom) soil type for the GBM river basins as obtained from the Food and Agriculture Organization. Maps are intentionally qualitative (no color coding) to represent the overall diversity in

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Alexandrede S. Pinto, Mercedes M. C. Bustamante, Maria Regina S. S. da Silva, Keith W. Kisselle, Michel Brossard, Ricardo Kruger, Richard G. Zepp, and Roger A. Burke

combination of grasses and legumes and the rotation of crop to pasture are alternative management techniques considered to be economically viable for the improvement of the soil fertility ( Toledo 1985 ). Nitrogen fertilizers are very expensive and potentially harmful to the environment due to their loss to the atmosphere and surface waters via leaching. There are no data, at least to our knowledge, about the impacts of restoration treatments on soil trace gas fluxes. Trace gases contribute to greenhouse

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John Risley, Hamid Moradkhani, Lauren Hay, and Steve Markstrom

1. Introduction Findings from Bernstein et al. ( Bernstein et al. 2007 ) describe how climate change resulting from increasing anthropogenic greenhouse-gas concentrations in the atmosphere will cause spatial and temporal alterations in the distribution of water resources in river drainage basins during the twenty-first century. To analyze potential shifts in water resources, climate output from general circulation models (GCMs) has often been input to hydrologic models that are used to simulate

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Christine Wiedinmyer, Xuexi Tie, Alex Guenther, Ron Neilson, and Claire Granier

1. Introduction Biogenic emissions, including volatile organic compounds (VOCs) and particulate matter (PM), play an important role in regional air quality processes and global atmospheric chemistry. Isoprene (C 5 H 8 ) is the predominant VOC emitted by vegetation. This compound is very reactive in the atmosphere and contributes to the reactions that control the concentrations and lifetimes of longer-lived species. In certain regions, it has been shown that isoprene plays a key role in the

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Gregory P. Asner, David E. Knapp, Amanda N. Cooper, Mercedes M. C. Bustamante, and Lydia P. Olander

canopy tropical forests. Science 284 : 1832 – 1835 . Duivenvoorden , J. F. 1996 . Patterns of tree species richness in rain forests of the middle Caqueta area, Colombia, NW Amazonia. Biotropica 28 : 142 – 158 . Ferreira , L. G. , H. Yoshioka , A. Huete , and E. E. Sano . 2003 . Seasonal landscape and spectral vegetation index dynamics in the Brazilian Cerrado: An analysis within the Large-Scale Biosphere–Atmosphere Experiment in Amazônia (LBA). Remote Sens. Environ. 87

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