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M. Issa Lélé, Lance M. Leslie, and Peter J. Lamb

.g., Webster 1994 ) and also because the natural variability of weather and climate at both regional and global scales is regulated by the water cycle (e.g., Eltahir and Bras 1996 ). Accordingly, research on water vapor flux and its convergence has both scientific and societal value. The WAM rainfall results from the moisture fluxes originating from many sources during the summer season. Over 80% of the annual precipitation falls during June–September when the intertropical front (ITF) extends farther

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Peter J. Lamb, Diane H. Portis, and Abraham Zangvil

1. Introduction Central to atmospheric behavior on a range of space and time scales is the relative importance of horizontal water vapor advection versus the vertical moisture flux from the earth’s land and ocean surfaces. At the small-scale extreme, the interaction of these moisture sources and their associated thermodynamic and dynamic processes contributes to the development of shallow cumulus clouds (e.g., Krishnamurti et al. 1980 ; Rabin et al. 1990 ; Chen and Avissar 1994 ; Berg and

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Robert A. Clark III, Zachary L. Flamig, Humberto Vergara, Yang Hong, Jonathan J. Gourley, Daniel J. Mandl, Stuart Frye, Matthew Handy, and Maria Patterson

M. Zhan , 2015 : Enabling big geoscience data analytics with a cloud-based, MapReduce-enabled and service-oriented workflow framework . PLoS One , 10 , e0116781, doi: 10.1371/journal.pone.0116781 . Liang , X. , D. Lettenmaier , E. Wood , and S. Burges , 1994 : A simple hydrologically based model of land surface water and energy fluxes for general circulation models . J. Geophys. Res. , 99 , 14 415 – 14 428 , doi: 10.1029/94JD00483 . 10.1029/94JD00483 Macharia , D. , T

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Abdou L. Dieng, Saidou M. Sall, Laurence Eymard, Marion Leduc-Leballeur, and Alban Lazar

-hPa convergence humidity flux. b. Comparison between DUO and SOLO systems In this subsection we address some responses to the first question of the introduction by comparing properties between DUO systems (system with a previous system) and SOLO systems (system without a previous one). However, because of the underestimation of north systems, the comparison results of system coming from the south zone will only be discussed hereafter. 1) Statistical results Table 2 and Fig. 8 show the

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Kerry H. Cook and Edward K. Vizy

simulation, as seen in Fig. 10 . In contrast, precipitation rates in the Congo basin are 1–2 mm day −1 greater in the 21C simulation. The decrease in precipitation over Tanzania and southern Kenya in the 21C simulation is associated with anomalous moisture transport and divergence in the overlying layer that carries moisture away from this region and into the Congo basin. The vectors in Fig. 10 are the 800-hPa moisture advection differences. A westward moisture flux between 850 and 600 hPa develops

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John G. Dwyer, Michela Biasutti, and Adam H. Sobel

strength and extent of the Hadley cell affecting the amplitude of precipitation and SST via changes in the surface wind speed on turbulent surface fluxes; an increase in low-level water vapor vertically advected by the Hadley cell leading to an increase in the amplitude of precipitation; changes in the timing and strength of the annual cycle of surface heat fluxes affecting the annual cycle of surface temperature; increased vertical stability later in the year due to enhanced warming aloft delaying the

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Lisa Hannak, Peter Knippertz, Andreas H. Fink, Anke Kniffka, and Gregor Pante

cooler but also drier air inland. More cooling is caused by outgoing longwave radiation, either from the surface before cloud formation or from cloud top afterward. If radiative cooling is anomalously strong, the surface layer can become decoupled from the lower troposphere, impeding cloud formation ( Schrage et al. 2007 ). Depending on vertical stability, which in turn depends on differential temperature advection and radiative cooling, shear-generated turbulent fluxes of heat and moisture can

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Zewdu T. Segele, Michael B. Richman, Lance M. Leslie, and Peter J. Lamb

correlation patterns continue in the zonal wind at pressure levels greater than 250 hPa. The positive correlation indicates a likelihood of enhanced Kiremt rainfall with increased Tu100 over southern Europe. Another potential predictor involving the mass field was found over the western equatorial Indian Ocean in association with the meridional flux of geopotential height at 500 hPa (ϕv500) during March ( Fig. 2 , middle). The main correlation signal was linked to the meridional wind (v500), but including

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Thomas Engel, Andreas H. Fink, Peter Knippertz, Gregor Pante, and Jan Bliefernicht

lesser extent, from evaporation at the continental surface. A convergent humidity flux [with the specific humidity q (kg kg −1 ) and horizontal wind vector (m s −1 )] then causes an accumulation of moisture in the atmospheric column as TPW (kg m −2 ): where p sfc (hPa) is the surface pressure and g = 9.81 m s −2 the gravitational acceleration. The convective available potential energy (CAPE; J kg −1 ; Emanuel 1994 ) is a common measure of convective instability: Here, α pcl and α env

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Susan Stillman, Xubin Zeng, and Michael G. Bosilovich

5, respectively), the uncertainty is still high ( Sillmann et al. 2013 ; Geil et al. 2013 ). Soil moisture is another major component of the terrestrial water cycle and is driven by precipitation. It helps regulate the surface energy balance by affecting the partitioning of available energy flux into latent and sensible heat fluxes at the surface, particularly in moisture-limited regions. Gravimetric measurement is the most accurate way to measure soil moisture, but this only represents a point

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