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Joseph D. White, Neal A. Scott, Adam I. Hirsch, and Steven W. Running

forest can accumulate aboveground biomass at a rate of 5.0 to 10.0 Mg of dry matter per hectare (1 ha = 10 000 m 2 ) per year ( Uhl et al. 1988 ; Brown and Lugo 1990 ), equivalent to roughly 2.5 to 5.0 Mg of carbon. Earlier studies suggest that the current annual carbon uptake by regrowing forests is small relative to deforestation loss to the atmosphere but that this rate will increase as more land is abandoned in the future ( Salimon and Brown 2000 ; Fearnside and Guimarães 1996 ). Previous

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M. C. Hansen, R. S. DeFries, J. R. G. Townshend, M. Carroll, C. Dimiceli, and R. A. Sohlberg

increase in surface temperature that is captured in the thermal bands. While the MODIS sensor has bands for measuring surface temperature [band 31 (10780–11280 nm) and band 32 (11770–12270 nm)], they are not currently processed for use in land cover mapping. There is a surface temperature product ( Wan et al., 2002 ) that employs these bands, but its algorithms are land cover dependent, precluding its use in mapping surface cover. Bands 31 and 32 of the MODIS instrument are used to derive surface

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Nicolas Schneider, Werner Eugster, and Barbara Schichler

were not analyzed in this study. While the atmospheric input data for the top and lateral boundaries prescribed to the model (see section 2.6 .) were identical for all simulations, the physical properties of the soil and the surface were adjusted to represent the particular land use of each simulation. Additionally, all simulations were initialized with the same vertical profile of virtual potential air temperature, horizontal wind speed, and water vapor mixing ratio as well as identical ground

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Sarah E. Perkins

simulation of the future climate. This assumption cannot be tested because we cannot assess a model for events that have not yet occurred. Nonetheless, it is generally accepted that, if a model performs poorly in the current climate, then it will continue to do so in the future (e.g., Jun et al. 2008 ). Therefore, quantifying model performance allows the user to decide if the model in question should be excluded in future projections, which may lead to a reduction in the uncertainty in future

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Charles P-A. Bourque and Quazi K. Hassan

deserts (e.g., 120–170 mm versus 40–60 mm yr −1 ; Table 1 ), but the amount is insufficient to be ecologically significant for oasis maintenance. A more significant source of water to the oases is the generation of meltwater in the Qilian Mountains. The meltwater usually flows during the spring-to-summer warming of the mountain glaciers and previous-winter snow cover ( Ji et al. 2006 ). Glacial meltwater currently accounts for about 22% of the total direct supply of inland river water in NW China

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Richard Seager, Nathan Lis, Jamie Feldman, Mingfang Ting, A. Park Williams, Jennifer Nakamura, Haibo Liu, and Naomi Henderson

thanks to Powell [with assistance from his biographer, Stegner (1954) ], it has been firmly etched into the nation’s psychogeography: a boundary with “broad and long-standing cultural and ecological significance” ( Simon 2010 , p. 97). It is readily visible from space, as the user of Google Earth can quickly verify, and is also plain to window seat passengers on airplanes flying across the continent. In his classic study of the Great Plains, Walter Prescott Webb preferred the 98th meridian as the

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J. Alcock

forest ecosystem is used to demonstrate the method. 2. The Amazon basin ecosystem Current practice in the Amazon basin is causing rapid changes to its tropical forest ecosystem. Most important are the agricultural, logging, and mining activities that cause permanent clearing of the forest at rates of about 0.5% yr –1 ( Skole and Tucker, 1993 ; Nepstad et al., 1999 ). Simple models based on linear or even exponential extrapolations imply that the forest could withstand this assault on its viability

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Nazzareno Diodato and Gianni Bellocchi

following years ( Richard 2007 ). The environmental and economic impact of these events can be high in several regions ( Kunkel et al. 1999 ; Alcántara-Ayala 2002 ), especially in agricultural and river-torrential areas ( Thornes and Alcántara-Ayala 1998 ; Camarasa Belmonte and Segura Beltrán 2001 ; Ramos and Mulligan 2003 ). The European southernmost regions are especially more sensitive to erratic rainfalls and are currently threatened by land degradation leading to a lowering in water resource

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Zhijuan Liu, Xiaoguang Yang, Xiaomao Lin, Kenneth G. Hubbard, Shuo Lv, and Jing Wang

growth cycle ( Lobell et al. 2009 ). Hence, a large exploitable gap exists between current yields and what is theoretically achievable under ideal management. The demonstration of yield gaps between potential yield and actual farmers’ yield for cereal crops provides an essential framework within which to prioritize research and policy efforts aimed at reducing these gaps ( Abeledo et al. 2008 ; Neumann et al. 2010 ; Laborte et al. 2012 ; Mueller et al. 2012 ). It is acknowledged that yield gaps

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Mark R. Jury

longitude–time plots of 3-hourly CMORPH rainfall and 6-hourly MERRA 600-hPa winds and specific humidity were averaged 8°–20°N latitude from 10° to 60°E, 22–29 August 2009. MERRA boundary layer winds over the Red Sea and a 25 August radiosonde profile at Abha, Saudi Arabia (18.2°N, 42.6°E; 2093 m), provide insights. HYSPLIT ensemble back trajectories in the 48 h before the convective outbreak were calculated at two end points (18°N, 39°E and 13°N, 42°E) in three vertical levels (1000, 3000, and 5000 m

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