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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

1. Introduction The Prairie Pothole Region (PPR) contains between 5 and 8 million wetland basins in small depressions left behind by the most recent Pleistocene glaciation. The PPR provides immense biological and ecosystem services to our society ( Johnson et al. 2010 ). First and foremost, the region acts as an ideal waterfowl breeding habitat, producing 50%–80% of North American ducks in late spring and summer ( Batt et al. 1989 ). This 800 000 km 2 region spans five states (Montana, North

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

(1890) , pp 775-6] Powell correctly notes the west–east precipitation gradient and then appears to attribute the full aridity gradient to the additional fact that the air, having crossed the Rockies, is exceedingly dry and warm, having been drained of its moisture on ascent and adiabatically warmed on descent. He correctly notes that such dry, warm air will extract moisture from the soil and vegetation. The grasslands of North America in the arid-to-semiarid plains are clearly partly a consequence

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Jacob O. Sewall

1. Introduction The distribution of precipitation over western North America is highly dependent on storm tracks and exhibits substantial latitudinal and seasonal variation. During the dry season (May through October, henceforth referred to as summer), major storms are generally isolated along the coast in the Pacific Northwest, the Canadian Rockies, and Alaska, and the remainder of western North America receives little precipitation ( Figure 1a ). During the wet season (November through April

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Christopher Potter, Shyam Boriah, Michael Steinbach, Vipin Kumar, and Steven Klooster

, between time series of SST anomalies and spatially explicit estimates of ecosystem processes on the land. The main purpose of this study is to make an assessment of the terrestrial vegetation regions in North America that have been most strongly influenced by global ocean–atmosphere processes affecting localized land climate. The latest generation of the National Aeronautics and Space Administration’s (NASA’s) Earth-observing satellites is providing unprecedented records of change in terrestrial

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Nancy H. F. French, Donald McKenzie, Tyler Erickson, Benjamin Koziol, Michael Billmire, K. Arthur Endsley, Naomi K. Yager Scheinerman, Liza Jenkins, Mary Ellen Miller, Roger Ottmar, and Susan Prichard

nonforest cover types (e.g., Guild et al. 1998 ), this translates into a substantial uncertainty for a model that assigns fuel properties based on general land-cover type, as many models do ( Hyer and Reid 2009 ). The uncertainties in emissions from global-scale models are also driven by the accuracy of the burned area estimates they use. Giglio et al. (2010) found that the L3JRC and GLOBCARBON burned area products accounted for substantially more burned area in North America than reported by fire

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Jacqueline J. Shinker and Patrick J. Bartlein

1. Introduction The El Niño–Southern Oscillation (ENSO) is one of the more prominent modes of variability observed in the global climate system and, while focused on the Pacific tropical ocean–atmosphere system, also has important remote influences in North America. ENSO variations on climate include changes in surface air pressure, surface and upper-level winds, and temperature and precipitation throughout the tropical Pacific Ocean ( Kiladis and Diaz 1989 ; Philander 1990 ; Ropelewski and

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

increases the complexity of interactions between vegetation and climate (see below). The vast grasslands over midwestern North America ( Figure 1 ; hereafter North American Grasslands) represent a typical semiarid environment in the northern midlatitudes, where variations of vegetation are closely associated with soil moisture (e.g., Woodward 1987 ; Churkina and Running 1998 ). At the same time, climate model studies (e.g., Koster et al. 2004 ) have suggested this region is one of the “hot spots

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C. Potter, S. Klooster, P. Tan, M. Steinbach, V. Kumar, and V. Genovese

-scale carbon fluxes and to better understand climate control patterns over terrestrial carbon sinks. The similar CASA NPP model application by Hicke et al. ( Hicke et al., 2002 ) to North America began to address a subset of these issues. The scope of our study goes well beyond those of previous CASA applications, however, in that we present here the first of a three-part global biosphere analysis of variability in CO 2 sinks, starting with North America, and subsequently extending the analysis to Eurasia

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Weile Wang, Bruce T. Anderson, Dara Entekhabi, Dong Huang, Robert K. Kaufmann, Christopher Potter, and Ranga B. Myneni

1. Introduction In the first part of this study ( Wang et al. 2006 , hereafter W1 ), statistical techniques are used to detect and analyze the influence of vegetation on climate variability over the North American Grasslands. Results indicate significant Granger causal relationships ( Granger 1969 ; Granger 1980 ) from lagged anomalies of vegetation activity to variations of summertime precipitation and surface temperature, particularly when time lags are longer than 2 months ( W1 ). That is

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

the beginning of this century. But now climate change caused by rising greenhouse gases from fossil fuel burning is advancing. Based on the most recent climate model projections from phase 5 of the Coupled Model Intercomparison Project (CMIP5) and analyzed by the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5), many workers have reported that North America will see, over the coming decades, a marked transition in hydroclimate. Precipitation is expected to decline in

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