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Charles W. Lafon and Steven M. Quiring

are about the same as those on the Blue Ridge. Lafon and Grissino-Mayer ( Lafon and Grissino-Mayer 2007 ) suggested that a regime of less frequent but heavier precipitation events leads to longer dry spells and more fire in the Blue Ridge than the Appalachian Plateau, with a less variable regime of frequent, light precipitation events that keep fuels moist for much of the time. In the current paper, we follow up on that study to determine whether, indeed, the Blue Ridge has greater precipitation

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Marc L. Fischer, David P. Billesbach, Joseph A. Berry, William J. Riley, and Margaret S. Torn

1. Introduction Land surface exchanges of energy, water, and CO 2 are the dominant factors affecting near-surface air temperatures, boundary layer CO 2 concentrations, boundary layer development and structure, cloud development, and precipitation. In the case of energy budgets and surface climate, previous work has shown that spatial complexity and temporal variations in land cover generate variations in climate at the regional scale ( Song et al. 1997 ; Doran et al. 1998 ; Cooley et al

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Chang Liao and Qianlai Zhuang

grasslands, the maximum correlation between NDVI and water deficits is found to be around 1 month during the growing season, which means the time lag might be 1 month ( Wang et al. 2001 ). For woodlands, the time lag is approximately 2 months in summer. The time lag for agricultural ecosystems is from 3 to 6 months ( Rouault and Richard 2003 ). In summary, different PFTs have different time lags in response to droughts. However, despite the rich knowledge of time-lag effects, current ecosystem models

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In-Young Yeo, Steven I. Gordon, and Jean-Michel Guldmann

hydrological impacts of land-use changes under such a scenario. This ad hoc scenario method is widely used to determine the best management plans or to prioritize environmentally sensitive areas for preservation. Another limitation of the current approach is related to the shortcomings of hydrological models. Although fully distributed physical models are available, runoff simulation modeling based on the SCS curve number method is the most widely used tool because of its simplicity and good accuracy A

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Marcello Gugliotta, Jonathan G. Fairman Jr., David M. Schultz, and Stephen S. Flint

plausible reconstructions of past geographies (i.e., land–sea distribution, ocean bathymetry, continental topography, land cover, and vegetation), atmospheric composition, solar input, and Earth’s orbital parameters as boundary conditions. For time-slice simulations, the model is run to an equilibrium state to determine the climate achieved under these specific boundary conditions and other forcings. Paleoclimate modeling studies have become an increasingly important and popular way to understand Earth

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Robert Paul d'Entremont and Gary B. Gustafson

, plans call for the SERCAA model to replace the current U.S. Air Force (USAF) operational cloud analysis model, the Real-Time Nephanalysis (RTNEPH), in the summer of 2002. In the coming years, archived cloud analyses from this model will offer an alternative global cloud record for climate studies. As such, it is important to document and describe the retrieval technique in order to better understand and use its cloud products. The RTNEPH operates on two-channel data, generally obtained from Defense

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L. S. Rose, J. A. Stallins, and M. L. Bentley

–atmosphere characteristics can initiate and enhance convection and precipitation. Nonlinear interactions among surface friction, momentum drag, and urban heating can induce downwind convergence ( Rozoff et al. 2003 ). Urban heating may lead to the formation of a downwind updraft cell that strengthens as boundary layer stability or wind speed decreases ( Baik et al. 2001 ; Baik et al. 2007 ). As urban heating intensifies, precipitation may move closer to the source of heating ( Thielen et al. 2000 ). Aerosol size and

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Lauren E. Hay, Steven L. Markstrom, and Christian Ward-Garrison

1. Introduction In recognition of the vulnerability of freshwater resources to changing climate, many studies have sought to examine the effects of climate change on components of the hydrologic budget. The most common approach has been to combine basin-scale hydrologic models with climate-change scenarios derived from general circulation model (GCM) output ( Buytaert et al. 2009 ). GCMs are considered the most advanced tool currently available for simulating the effects of increasing

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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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