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Laurel L. De Haan and Masao Kanamitsu

1. Introduction It has been well understood for many years that the response of general circulation models to tropical sea surface temperatures (SSTs) is of primary importance to climate prediction. However, it has become apparent more recently that soil moisture has an important secondary role. As a result, there has been an increased interest in understanding the impact of soil moisture on near-surface temperature and precipitation in general circulation models (GCMs). The influence of soil

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Sun Wong, Catherine M. Naud, Brian H. Kahn, Longtao Wu, and Eric J. Fetzer

1. Introduction A key question related to climate sensitivity is how clouds and precipitation respond to changes in the large-scale circulation ( Bony et al. 2015 ). A more direct and fundamental question is how clouds and precipitation respond to changes in moisture flux convergence induced by changes in the large-scale circulation. In this work, we investigate moisture balance in extratropical cyclones (ETCs) to quantify coupling of precipitation and cloud processes to the large

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Clemens Schwingshackl, Martin Hirschi, and Sonia I. Seneviratne

role of soil moisture, since it affects various exchange processes at the surface. Seneviratne et al. (2010) provide an overview on the role of soil moisture for climate variability and land–atmosphere exchange. Based on both observational and modeling studies, various authors have shown that soil moisture has an impact on the evolution of near-surface air temperature ( Seneviratne et al. 2006 ; Koster et al. 2009b ; Jaeger and Seneviratne 2011 ; Seneviratne et al. 2013 ; Hirschi et al. 2014

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Randal D. Koster, Rolf H. Reichle, Siegfried D. Schubert, and Sarith P. Mahanama

scales characterizing the variabilities of soil moisture, evapotranspiration, and streamflow. As outlined in section 4 below, the overall spatial connectedness of hydrological variations can have important impacts on measurement strategies as well as on hydrological and climatic processes that influence society; it is more than a statistical curiosity. Available relatively recently to the hydrological community are global gridded datasets of satellite-derived moisture in the top several centimeters

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Peter Knippertz and Jonathan E. Martin

1. Introduction A number of studies have related extraordinary cool season precipitation events in western North America to bands of enhanced moisture transport from low latitudes in connection with landfalling extratropical cyclones from the Pacific Ocean (e.g., Higgins et al. 2000 ; Cavazos and Rivas 2004 ; Ralph et al. 2004 ; Bao et al. 2006 ). The fairly frequent bands connecting Hawaii with the Pacific Northwest region are widely known as the “pineapple express.” Methodically, the

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Matthew Newman, George N. Kiladis, Klaus M. Weickmann, F. Martin Ralph, and Prashant D. Sardeshmukh

1. Introduction Perhaps the most striking feature in a satellite loop of the earth is that the atmosphere transports water across great distances. While this transport appears to occur more frequently in certain regions, it is not steady; rather, it is characterized by numerous transient features of many scales. Thus, to understand atmospheric moisture transport, including the dual role it plays in the global energy cycle and as the source of water over the continents, there is a need to

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Yanhong Gao, L. Ruby Leung, Yongxin Zhang, and Lan Cuo

Model (CAM) shortwave and longwave scheme ( Collins et al. 2004 ), the single-moment three-class cloud microphysics (WSM3), Grell–Devenyi ensemble cumulus convective scheme ( Grell 1993 ), the Yonsei University (YSU) boundary layer scheme ( Hong and Pan 1996 ), and the Noah land surface model ( Chen and Dudhia 2001 ) were used in this simulation. The regional simulation produced model outputs at 3-hourly intervals for analysis of moisture budgets. Results of the regional simulation are interpolated

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Mario Siqueira, Gabriel Katul, and Amilcare Porporato

1. Introduction The coupling between soil moisture, land surface fluxes, and the initiation of convection, which may lead to convective rainfall, remains an open research problem and has attracted much recent inquiry ( Dirmeyer et al. 2006 ; Kim and Wang 2007 ; Kochendorfer and Ramirez 2005 ; Koster et al. 2004 ; Koster and Suarez 2004 ; Lawrence and Slingo 2005 ; Mahanama and Koster 2005 ; Santanello et al. 2007 ; Wang et al. 2007 ; Fennessy and Shukla 1999 ). The reason this problem

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

Steenburgh 2005 ; Gu et al. 2006 ). For example, the impact of soil moisture on precipitation (and vice versa) is largely determined by a series of nonlinear processes ranging from soil moisture dynamics to planetary boundary layer (PBL) turbulence. As a whole, these processes determine the “strength” of the coupling between the land surface and atmosphere, which, as a result, varies as a function of heat and moisture fluxes that are dependent on many different LA properties, such as vegetation height

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Natasa Skific, Jennifer A. Francis, and John J. Cassano

static energy transport supplies approximately 98% of the energy annually lost to space by the Arctic north of 70°N ( Nakamura and Oort 1988 ). Because the Arctic warms more than lower latitudes, one expects that the lower-tropospheric meridional temperature gradient should relax, poleward advection of sensible heat should decrease, and Arctic warming should weaken. Simulations with global climate models support this reasoning, but they also suggest that increases in moisture transport will more than

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