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Forrest M. Hoffman, William W. Hargrove Jr., David J. Erickson III, and Robert J. Oglesby

average are presented. While trends can be seen in other regimes in individual runs for North America, the ensemble average has only a significant decrease in spatial area of cluster 26: the coldest and driest Canadian winter conditions. In Antarctica, the coldest and driest conditions in the middle of the continent give way to climate regimes that typify current coastal conditions. As with North America, the spatial area of cluster 26 decreases in Eurasia. For Eurasia this regime represents the

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Arindam Samanta, Sangram Ganguly, Eric Vermote, Ramakrishna R. Nemani, and Ranga B. Myneni

aerosol optical thickness (AOT) was obtained from the level 3 daily joint aerosol/water vapor/cloud product (MOD08_D3) at 1° × 1° spatial resolution. These were obtained from the NASA Level 1 and Atmosphere Archive and Distribution System (LAADS) ( NASA 2011a ) for the months of July–September of the years 2000–06. We used the optical_depth_land_and_ocean_mean_mean data field from this product, which contains AOT at 550 nm. Similarly, monthly AOT was obtained from the level 3 monthly joint aerosol

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Kenta Ogawa and Thomas Schmugge

and Dalu ( Prabhakara and Dalu, 1976 ) mapped the surface emissivity with 100-km resolution using the Nimbus-4 infrared interferometer spectrometer (IRIS) and found that emissivity at 9 μ m varied from 0.65 to 0.90. A map with a finer spatial resolution provided by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Moderate Resolution Imaging Spectrometer (MODIS) data would be a useful improvement for our understanding of the land–atmosphere interaction. ASTER

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Xuefeng Cui, Hans-F. Graf, Baerbel Langmann, Wen Chen, and Ronghui Huang

total area in 1957 to only 10% in 1986. As a result, soil erosion from the upper reaches and sediment redistribution in the middle and lower reaches have intensified. These effects might have contributed to the most severe flood in Chinese history in the Yangtze valley in 1998, affecting 223 million people and causing more than $36 billion (U.S.) in economic loss ( Zhang et al. 2000 ). In 1998, the Chinese central government recognized the disastrous consequences of forest degradation resulting in

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Daniel E. Comarazamy, Jorge E. González, Jeffrey C. Luvall, Douglas L. Rickman, and Pedro J. Mulero

1. Introduction Human activity in urban environments has impacts in the regional scale, such as changing the atmospheric composition, affecting the water cycle, and modifying ecosystems. Nevertheless, our understanding of the role of urbanization in the ecoclimate system is incomplete, yet it is critical to determine how in coastal environments the atmosphere–ocean–land–biosphere components act reciprocally in a connected system. The most clear mesoscale indicator of environmental

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Christopher E. Doughty, Scott R. Loarie, and Christopher B. Field

ecophysiological/aerodynamic component for controlling land surface temperature ( Dickinson and Henderson-Sellers 1988 ; Juang et al. 2007 ). Trees are rougher surfaces than crops or pasture, and they have very deep roots, which enable them to access deep soil water reserves and act as better conduits for water vapor to the atmosphere ( Nepstad et al. 1994 ), thus increasing evaporative fluxes to the atmosphere ( Bala et al. 2007 ). There have been large increases in albedo in South America as dark forests

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David M. Mocko and Y. C. Sud

1. Introduction The Biosphere–Atmosphere Transfer Scheme of Dickinson et al. ( Dickinson et al., 1986 ) and the Simple Biosphere Model (SiB) of Sellers et al. ( Sellers et al., 1986 ) were the two landmark works that set the stage for more realistic parameterizations of the diurnal cycle of land surface fluxes and soil hydrology. Ever since, numerous other schemes have appeared in the literature. The Project for Intercomparison of Land-surface Parameterization Schemes experiment ( Henderson

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Jianjun Ge

1. Introduction An increasing number of studies suggest that the biosphere exerts considerable control over the physical system in the atmosphere (e.g., Feddema et al. 2005 ; Cotton and Pielke 2007 ; Ge et al. 2007 ; Mahmood et al. 2010 ). Land-cover change affects climate through forcing and feedback processes ( Betts 2006 ). Large-scale land surface changes can provide sources or sinks of carbon dioxide and affect the concentration of mineral dust aerosol particles ( Solomon et

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Daniel Brown and Gerhard Reuter

) The location of the oil sands and Fort McMurray in Alberta (modified from Brown et al. 2011 ). (middle) The oil sands land cover in 2007 (modified from Brown et al. 2011 ). (right) Our model modifications. We modeled the oil sands development as an approximately circular 650-km 2 disturbance of barren ground (pink area). We added waste heat to the atmosphere in a smaller area within the center of the disturbance (blue area). ©Earth Interactions. Used with permission. Research investigating the

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

1. Introduction The 100th meridian was conceptualized by the nineteenth-century explorer, scientist, and director of the U.S. Geological Survey and Bureau of Ethnology John Wesley Powell as the clearly demarcated divide between America’s arid west and humid east ( Powell 1879 , 1890 ). In Part I of this two-part paper, we showed the validity of this conceptual divide in terms of a sharp zonal gradient in aridity across the Great Plains, elucidated the physical processes in the atmosphere that

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