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Pang-chi Hsu and Tim Li

.g., Hendon and Salby 1994 ; Maloney and Hartmann 1998 ). While the previous studies have identified the important role of the PBL convergence asymmetry in the eastward propagation, the quantitative examination of relative roles of free-atmospheric wave dynamics, surface fluxes, and air–sea interaction induced SST changes in causing the phase leading of the PBL convergence remains absent. Some recent studies have focused on the atmospheric moisture dynamic in relation to the MJO development and

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Christian Sutton, Thomas M. Hamill, and Thomas T. Warner

assessment of the state of the land surface may affect the subsequent weather forecast. As the ground surface heats up during the day, sensible energy is transferred to the atmosphere, moisture evaporates from the soil or transpirates from plants (latent heating), and the soil below is heated. The partitioning of the available energy among sensible, latent, and ground heat fluxes depends on many variables, in particular soil moisture. Generally, the drier the soil, the smaller the daytime latent heat

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Pang-Chi Hsu, Tim Li, and Hiroyuki Murakami

convergence ( Hendon and Salby 1994 ; Li and Wang 1994 ; Wang and Li 1994 ; Maloney and Hartmann 1998 ) and moisture ( Sperber 2003 ; Kiladis et al. 2005 ; Benedict and Randall 2007 ) in the planetary boundary layer (PBL). Recent studies emphasized the role of moisture dynamics in the eastward propagation of the MJO (e.g., Maloney 2009 ; Hsu and Li 2012 ; Sobel and Maloney 2013 ). By analyzing column-integrated moist static energy (MSE) and moisture budgets from a general circulation model

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Trent W. Ford, Steven M. Quiring, Chen Zhao, Zachary T. Leasor, and Christian Landry

1. Introduction Soil moisture is a critical variable, impacting and informing a wide variety of scientific disciplines and applications. Soil moisture influences the climate system through modification of energy and moisture fluxes into the boundary layer, thereby influencing temperature, humidity, and precipitation ( McPherson 2007 ; Seneviratne et al. 2010 ; Santanello et al. 2011 ). This influence, or memory, from anomalously wet or dry soils can have a persistent impact on the atmosphere

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Xiuzhen Li, Wen Zhou, Deliang Chen, Chongyin Li, and Jie Song

without eastward migration during WP El Niño ( Yuan et al. 2012 ). In the decaying summer, the WPSH shifts westward during CT El Niño, while it reinvigorates after short-term weakness during WP El Niño ( Feng et al. 2011 ). Given the great discrepancies in the responses of atmospheric circulations over East Asia and the importance of these circulations to water vapor transport, it is worth investigating how the two types of El Niño affect water vapor transport and thus the moisture supply to eastern

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O. Merlin, A. Chehbouni, G. Boulet, and Y. Kerr

1. Introduction Rainfall and soil moisture are key variables of the terrestrial hydrosphere. Whereas rainfall provides the amount of available water at the surface, soil moisture controls the partitioning of rainfall into runoff and infiltration and the incident energy into sensible and latent heat flux. The knowledge of both complementary variables is hence critical for achieving efficient and sustainable water management and for improvements in climate change prediction. Both variables are

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Shu-Peng Ho, Ying-Hwa Kuo, and Sergey Sokolovskiy

(from 0 to 18 km) to ∼1 km at 20 km, which is much higher than that of most other satellite data ( Kursinski et al. 1997 ). In addition to GPS RO soundings, high-vertical-resolution temperature and moisture profiles can be obtained from Atmospheric Infrared Sounder (AIRS) measurements. With a very high spectral resolution ( λ /Δ λ ≈ 1200), AIRS can measure vertical temperature and moisture profiles with about 1–2-km vertical resolution ( Aumann et al. 2003 ). The temperature root-mean-square error

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Liang Guo, Nicholas P. Klingaman, Pier Luigi Vidale, Andrew G. Turner, Marie-Estelle Demory, and Alison Cobb

of floods in the eastern United States ( Villarini et al. 2014 ). About 14% of total onshore flux over the coast of the North America can be attributed to the Atlantic TCs ( Xu et al. 2016 ). The aforementioned studies suggest that TCs have the potential to make a substantial contribution to the water cycle over EA. The fact that TC contributions to the atmospheric moisture budget have received little attention may be explained by the perceived dominance of the EASM, one of the most intense

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Feng Hu, Tim Li, Jianyun Gao, and Lisheng Hao

envelope and MJO-scale moisture was assumed ( Thual et al. 2014 ; Thual and Majda 2015 , 2016 ). Yang and Ingersoll (2013 , 2014 ) put forward a gravity wave theory. The essence of this theory is the interference of westward and eastward inertia–gravity waves whose dispersion relations are not symmetric due to the beta effect. This theory, however, requires further observational validation. One school of recent studies emphasized the important role of perturbation moisture in MJO propagation

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Bart van den Hurk, Janneke Ettema, and Pedro Viterbo

1. Introduction Root zone soil moisture is a crucial variable in the climate system. Initial conditions in numerical weather prediction models of soil moisture for the upper meter of the soil are a crucial element in the forecast performance in midlatitudes spring/summer (e.g., Beljaars et al. 1996 ) and might extend predictability over land in the monthly to seasonal range ( Koster et al. 2004 ). Root zone soil moisture affects transpiration, strongly influencing the partitioning of available

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