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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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Ute C. Herzfeld, Sheldon Drobot, Wanli Wu, Charles Fowler, and James Maslanik

principles as well as options for handling missing data values and integrating boundaries of geographic areas. Standardization is necessary, wherever data from different sources or variables of different units are to be analyzed synoptically, as is the case in the WALE modeling and analysis project ( ). In our application, we use linear transformation of the range of data into the interval [0,1], and all calculations are performed inside a landmask outlining the study area

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Pedro Sequera, Jorge E. González, Kyle McDonald, Steve LaDochy, and Daniel Comarazamy

. Numerical simulations performed on the Los Angeles basin by Sailor (1995) indicated that increasing albedo over downtown Los Angeles by 0.14 and over the entire basin by an average of 0.08 would result in decreased peak summertime temperatures by as much as 1.5°C, lowering boundary layer heights by more than 50 m and reducing the magnitude and penetration of the sea breeze. One-dimensional meteorological simulations by Taha et al. (1988) showed that localized afternoon air temperatures on summer

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Heather Tollerud, Jesslyn Brown, Tom Loveland, Rezaul Mahmood, and Norman Bliss

in the Great Plains typically covered larger areas and tended to have greater overall impacts than other weather events such as floods, freezes, and hail. Drought events affect large areas ( Sheffield et al. 2009 ), and the dominantly agricultural economic foundation of the Great Plains region is vulnerable to drought impacts ( Raz-Yaseef et al. 2015 ; Tadesse et al. 2015 ; Otkin et al. 2016 ). In this study, we use the NCA3 Great Plains region boundary and a set of ecoregions defined by

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Christopher J. Kucharik

management decision making across a large landscape. While land use policies are implemented by individuals, decision making is frequently based upon large-scale (e.g., county, crop reporting district, and state) regional assessments, occasionally guided by model projections. Some of the most important questions currently posed in agricultural research are how cropping systems and land management might be affected by future large-scale climate changes ( Doering et al., 2002; Reilly et al., 2002 ). The

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Mustapha El Maayar, Navin Ramankutty, and Christopher J. Kucharik

of Earth’s climate and its variability through effects of CO 2 on the Earth’s radiative budget ( Houghton et al. 2001 ). Consequently, current scientific knowledge suggests that evaluating the implications of the continual C a increase requires very sophisticated parameterizations to help understand the complex interactions between the different components of the Earth system. It is now well recognized that terrestrial ecosystems play a key role in fashioning the Earth’s climate and

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Tristan Ballard, Richard Seager, Jason E. Smerdon, Benjamin I. Cook, Andrea J. Ray, Balaji Rajagopalan, Yochanan Kushnir, Jennifer Nakamura, and Naomi Henderson

idealized climate scenarios with temporally and spatially uniform imposed temperature and precipitation changes to drive wetland models. These studies indicate that warming alone would tend to make the wetter eastern regions more favorable for waterfowl as cover cycles shorten. Farther west, significant increases in precipitation will be required to match the increased evaporative demand of a warmer climate, threatening the current westward extent of the PPR wetlands ( Larson 1995 ; Sorenson et al

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T. Scott Rupp, Xi Chen, Mark Olson, and A. David McGuire

annual burning of 5–15 Mha of boreal forest ( Stocks et al. 2002 ; Lavorel et al. 2005 ; Flannigan et al. 2006 ). Current estimates are that an average of 2.3 Mha burn annually across the North American boreal forest, with the amount of annual area burned ranging between 0.5 and 8 Mha ( Amiro et al. 2001 ; Kasischke et al. 2006 ; Csiszar et al. 2004 ), and there is a growing awareness of the importance and vulnerability of the region to forecast climatic change ( Weber and Flannigan 1997

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Julian C. Brimelow, John M. Hanesiak, and William R. Burrows

land–atmosphere interactions. At scales of a few kilometers, advection and turbulence mix out surface-induced variability in the convective boundary layer (CBL; Raupach and Finnigan 1995 ), so discontinuities must be long lived and cover a sufficiently large area before they can begin to significantly influence the evolution of the CBL ( Avissar and Chen 1993 ; Lynn et al. 1995 ; Lynn et al. 1998 ) and attendant thunderstorm activity. Oglesby et al. ( Oglesby et al. 2002 ) conducted modeling

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A. Park Williams, Joel Michaelsen, Steven W. Leavitt, and Christopher J. Still

climate change, trees are of particular concern. Changes in their growth and related ecological processes (e.g., recruitment, growth rate, mortality) can rapidly drive long-term modifications to ecosystem type; water and carbon cycling rates; and surface properties such as erosivity, albedo, snowmelt dynamics, and wind turbulence ( Bernstein et al. 2007 ). Within populations, changes in productivity are expected to be most rapid and measurable at and near ecotones, the boundaries between ecosystems

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