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Kun Yang, Toshio Koike, Ichirow Kaihotsu, and Jun Qin

1. Introduction Soil moisture is a highly variable parameter in semiarid regions, where strong coupling between soil moisture and precipitation are suggested by Koster et al. (2004) . Soil moisture estimation is imperative for hydrometeorological studies and water resources management (e.g., Pauwels et al. 2001 ; Wu and Dickinson 2004 ; de Goncalves et al. 2006 ), and how to estimate soil moisture with good accuracy is still a hot topic of land hydrology and satellite remote sensing. Land

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Christoph Rüdiger, Jean-Christophe Calvet, Claire Gruhier, Thomas R. H. Holmes, Richard A. M. de Jeu, and Wolfgang Wagner

1. Introduction Soil moisture is the governing variable for modeling soil surface-to-atmosphere energy exchanges and land surface model (LSM) initialization, as it controls both evaporation and transpiration from bare soil surfaces and vegetation covers. Consequently, a significant amount of studies have been and are currently being conducted to obtain soil moisture estimates through land surface modeling (e.g., Dirmeyer et al. 1999 ; Georgakakos and Carpenter 2006 ) and remotely sensed

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Huilin Gao, Eric F. Wood, Matthias Drusch, and Matthew F. McCabe

1. Introduction Soil moisture plays a unique role in land–atmosphere interactions by coupling the water and energy cycles through its control on evapotranspiration and runoff and consequently influencing boundary layer cloud formation and precipitation (e.g., Schär et al. 1999 ; Betts 2004 ; Koster et al. 2004 ). Although it is well recognized that accurate knowledge of real-time soil moisture conditions will enhance hydrological forecasts and potentially contribute to improving numerical

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Johannes Mayer, Michael Mayer, and Leopold Haimberger

patterns of net heat uptake by the oceans, where most of the excess heat arising from anthropogenic climate change is stored ( von Schuckmann et al. 2020 ). The atmospheric moisture cycle represents the link between the energy budget and the mass budget. Evaporation transfers water vapor and thus mass and latent heat into the atmosphere, which subsequently transports moisture to regions where precipitation exceeds evaporation, where the latent heat is released and warms the atmosphere. Changes to the

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Paolina Bongioannini Cerlini, Lorenzo Silvestri, Silvia Meniconi, and Bruno Brunone

, potential evaporation, and crop-yield information. Omorinbola (1986) evaluated the groundwater accretion by means of empirical equations as correlated to the magnitude of the saturated zone thickness, since such a parameter fluctuates with the rate of groundwater recharge. Soil moisture balance models as well as a regional runoff/storm duration relationship for assessing the effective precipitation have been used in Leach (1982) . In Chinnasamy et al. (2013) , the prediction of the groundwater

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Eric A. Aligo, William A. Gallus Jr., and Moti Segal

forecasts are sensitively dependent on the soil moisture initial condition uncertainty. Therefore, they suggested adding initial soil moisture perturbations to the existing suite of atmospheric perturbations and/or different models to improve ensemble spread. They used the Weather Research and Forecasting (WRF) Advanced Research WRF (ARW) model to show that two initial soil moisture analyses were different enough to produce 24-h rainfall differences at 5-km horizontal grid spacing that were similar to

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Rezaul Mahmood, Kenneth G. Hubbard, Ronnie D. Leeper, and Stuart A. Foster

particular focus on the boundary layer atmospheric moisture. Because of conversion from nonirrigated land use to irrigated cropland, it is expected that near-surface atmospheric moisture content will increase during the growing season. This is the primary motivation for analyzing T d data. The source of the T d data is the Automated Weather Data Network (AWDN) of the northern Great Plains (NGP) ( www.hprcc.unl.edu ). This is the oldest mesoscale network of the United States, operated and maintained

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Christopher G. Marciano and Gary M. Lackmann

coverage of the event suggested a link between Joaquin and the flooding, and in some cases indicated that Joaquin had served as a moisture source for the flooding rainfall (e.g., NWS 2015 ; NHC 2016 ). Other factors, such as a coastal front and Appalachian cold-air damming may have contributed as well, but these aspects are beyond the scope of this study. The goals of this paper are to 1) document the moisture transport mechanisms active during this event, and 2) quantify and elucidate Joaquin’s role

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Clark Evans, Russ S. Schumacher, and Thomas J. Galarneau Jr.

heat fluxes (e.g., Rotunno and Emanuel 1987 ). Rainfall along and ahead of the track of a TC over land contributes to increased soil moisture content of the sandy soils of the Australian desert. Such desert soils are excellent natural heat and moisture conductors. Daytime heating ahead of the TC warms these soils, contributing to latent heat fluxes sufficiently large so as to allow for vortex reintensification over land in an otherwise favorable environment for TC development (e.g., Emanuel et al

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Yonghong Yi, John S. Kimball, Lucas A. Jones, Rolf H. Reichle, and Kyle C. McDonald

. 2006 ). Incident solar radiation drives the surface energy budget, land surface evaporation, and photosynthetic uptake of CO 2 , whereas temperature and moisture availability determine rates of evapotranspiration, photosynthesis, and ecosystem respiration ( Churkina et al. 1999 ; Running et al. 2004 ). The diurnal range of surface air temperature is closely related to surface energy partitioning, surface moisture status, and atmospheric humidity ( Kimball et al. 1997 ), while surface air humidity

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