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Vivek K. Arora and George J. Boer

1. Introduction Vegetation affects climate by modifying the energy, momentum, and hydrologic balance of the land surface. Boundary layer exchanges of heat and momentum, evapotranspiration, and the absorption of solar radiation, are all influenced by vegetation and have important feedbacks on the global and regional climate. Vegetation influences climate via its physiological (stomatal conductance) and structural (leaf area index, root depth and distribution, height, and albedo) properties

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Christopher J. Watts, Russell L. Scott, Jaime Garatuza-Payan, Julio C. Rodriguez, John H. Prueger, William P. Kustas, and Michael Douglas

insights into the space–time characteristics of the rainfall in this area ( Gochis et al. 2004 ). Measurements of evaporation are much more difficult and very few have been made in the region, mainly in agricultural areas to study the consumptive use of important crops such as wheat, cotton, and grapes. Nonetheless, two previous campaigns over natural vegetation in the region should be mentioned: a study over desert shrub at the La Posa site near Hermosillo in 1995 ( Stewart et al. 1998 ) and the Semi

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Weile Wang, Bruce T. Anderson, Nathan Phillips, Robert K. Kaufmann, Christopher Potter, and Ranga B. Myneni

1. Introduction It is well known that terrestrial vegetation can influence climate through the exchange of energy, mass, and momentum between the land surface and the overlying atmosphere ( Pielke et al. 1998 ). As a major pathway through which soil water is transferred into the atmosphere, vegetation generally promotes the land–atmosphere water exchange via evapotranspiration ( Sellers et al. 1997 ; Gerten et al. 2004 ) and reduces surface temperatures by lowering the Bowen ratio ( Bounoua et

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Abigail L. S. Swann, Inez Y. Fung, Yuwei Liu, and John C. H. Chiang

and remotely through ecoclimate teleconnections (i.e., by changing large-scale thermal and energy gradients and hence atmospheric circulation). As the paleo-proxy records do not provide complete coverage in the spatial domain, we do not have a full picture of climate globally at any time in the past. We suggest that the influence of vegetation on atmospheric circulation patterns can be used to paint a broader view of global climate conditions. Here we show that the remote and local forcing of

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Edson E. Sano, Laerte G. Ferreira, and Alfredo R. Huete

with more than 450 vascular species per hectare, and occurs mostly in low-fertility and high-aluminum-toxicity oxisols ( Eiten 1993 ). In terms of climate, it presents two well-defined seasons: six months of dry conditions, from May to October, and six months of wet conditions, from November to April. The gentle topography, relatively low land prices, and the construction of Brasilia in 1964 have contributed greatly to convert natural vegetation into cultivated pastures and annual crops (mainly

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Vivek K. Arora and George J. Boer

1. Introduction The terrestrial biosphere plays an important role in determining the climate through a range of biophysical and biogeochemical processes. Terrestrial vegetation affects the way in which energy and water are exchanged between the land and the atmosphere on time scales of minutes to months, and the climatic implications of such biophysical interactions have been studied by various authors ( Charney 1975 ; Lean and Rowntree 1993 ; Xue 1997 ; Douville et al. 2000 ; Heck et al

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Theodore L. Allen, Scott Curtis, and Douglas W. Gamble

onset, duration, and magnitude exhibits interannual variability spatially (throughout the region) and temporally (during the boreal summer) ( Curtis and Gamble 2008 ) because of the El Niño–Southern Oscillation ( Curtis 2002 ), the North Atlantic Oscillation ( Giannini et al. 2001 ), and other factors. The reduction of precipitation, combined with associated reduced cloud coverage and related increased surface heating during the MSD, can negatively affect vegetation within the IAS region, resulting

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Young-Kwon Lim, Ming Cai, Eugenia Kalnay, and Liming Zhou

1. Introduction Global mean surface temperature time series derived from in situ observations reveal the interdecadal global warming over the last several decades ( Houghton et al. 2001 ). Many studies reported that this upward trend is significantly a result of primary human impacts such as greenhouse gases ( Houghton et al. 2001 ) and land use ( Pielke et al. 2002 ). The anthropogenic land-use impact on surface warming may become more important as the surface vegetation changes in the form of

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Seungbum Hong, Venkat Lakshmi, and Eric E. Small

1. Introduction It has been long recognized that atmospheric and land surface processes are correlated with each other. Climate and meteorological processes determine land surface characteristics such as the vegetation distribution, energy balance, and watershed hydrology ( Neilson 1986 ; Lu et al. 2001 ; Small and Kurc 2003 ; Weiss et al. 2004 ). Land surface processes in turn affect atmospheric temperature, humidity, precipitation, and radiative transfer ( Pielke et al. 1998 ; Lu et al

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R. D. Koster and G. K. Walker

of the Global Land–Atmosphere Coupling Experiment (GLACE-2; Koster et al. 2011 ) showed that an accurate initialization of soil moisture state can add significant skill to surface air temperature forecasts out to 2 months. The “lushness” of vegetation [as represented by the leaf area index (LAI)] also has a persistence that exceeds that of atmospheric variables ( Wang and Eltahir 2000 ; Zeng et al. 1999 ; Guillevic et al. 2002 ). Because vegetation state has a direct impact on, for example

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