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Keith J. Harding and Peter K. Snyder

. 2005 ). The availability of such a large quantity of water for ET has a sizeable effect on surface energy and water budgets ( Pielke 2001 ). Increases in latent heating with additional water are offset by decreases in sensible heating, resulting in changes to the surface temperature and moisture fields ( Barnston and Schickedanz 1984 ; DeAngelis et al. 2010 ; Kueppers et al. 2007 ; Ozdogan et al. 2010 ; Pielke 2001 ; Sacks et al. 2009 ). The repartitioning of net radiation into latent heating

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Enrique R. Vivoni

catchment response has been the lack of reliable simulations. Here, a distributed hydrologic model, tested against a distributed soil moisture and temperature dataset ( Vivoni et al. 2010 ), is employed. Vegetation changes are captured by linking remote sensing observations to model parameters that influence vegetation processes. This is a first step toward a fully dynamic representation of drought-deciduous ecosystems of the monsoon region (cf. Ivanov et al. 2008 ). The numerical experiments here are

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Ruth E. Comer and Martin J. Best

1. Introduction Soil moisture plays an important role in modifying the behavior of the atmosphere by its influence on land surface fluxes of moisture, energy, carbon, and trace gases [ Seneviratne et al. (2010) and references therein]. Of particular interest is the way in which the effects of these moisture and energy fluxes combine to create feedbacks on precipitation. Such feedbacks are complex because of their dependence on a variety of mechanisms. The scarcity of observations of soil

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Joseph A. Santanello Jr., Christa D. Peters-Lidard, Aaron Kennedy, and Sujay V. Kumar

1. Introduction Quantification of the land surface influence on extremes such as flood and drought is critical for both short-term weather and climate prediction. These dry and wet regimes are modulated by the strength and sensitivity of the land–atmosphere (L–A) coupling and, in particular, how anomalies in soil moisture are translated into and through the planetary boundary layer (PBL), ultimately favoring or suppressing the triggering and support of clouds and precipitation. Improved

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Keith J. Harding and Peter K. Snyder

sensible heating result in a cooler and more humid surface ( Adegoke et al. 2007 , 2003 ; Baidya Roy et al. 2003 ; Kueppers et al. 2007 ; Lobell et al. 2008 ; Mahmood et al. 2004 , 2006 ; Sacks et al. 2009 ), which drives opposing impacts on convection. Overall, increases in convective available potential energy (CAPE) from the increase in low-level moisture generally overwhelm the suppression of convection that results from increases in convective inhibition (CIN) from surface cooling

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Craig R. Ferguson, Eric F. Wood, and Raghuveer K. Vinukollu

complimentary, coregistered (in time and space) information on the state of the land surface (e.g., soil moisture, soil temperature, vegetation fraction, land cover type, leaf area index, and albedo), atmospheric profile (e.g., temperature, humidity, and precipitation), and surface radiation forcing, at spatial resolutions ranging from 250 m (MODIS) to 50 km (AIRS/AMSU). Aqua is set in a sun-synchronous orbit with equatorial crossing times of ~1330 and ~0130 local time (LT) on ascending and descending

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Agustín Robles-Morua, Enrique R. Vivoni, and Alex S. Mayer

radiation suggests that correspondence may exist between runoff mechanisms, which typically depend on seasonal wetness, and the land–atmosphere interactions arising during the NAM. Several studies have investigated how soil moisture plays a role in land–atmosphere exchanges and their impact on subsequent rainfall generation in the NAM region (e.g., Small 2001 ; Xu et al. 2004 ; Vivoni et al. 2009 ). This interaction arises from a positive soil moisture–rainfall feedback ( Eltahir 1998 ) that has been

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Xubin Zeng, Zhuo Wang, and Aihui Wang

shortwave and longwave fluxes, α is surface albedo, ε is surface emissivity, σ = 5.67 × 10 −8 W m −2 K −4 is the Stefan–Boltzmann constant, and T s is the surface skin temperature. Over arid regions, LH is much smaller than SH in magnitude and can be omitted (but it is still fully considered in Noah and CLM simulations here). The ground heat flux is where K soil is the soil thermal conductivity, which depends on soil composition, porosity, and moisture, and T soil is the soil temperature

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