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

position, tropical Atlantic sea surface temperature anomalies, the El Niño–Southern Oscillation (ENSO) phenomenon, and regional-scale atmospheric features—to account for the observed variations in rainfall. An overview is provided by Nicholson (2013) . Given the proximity of the extent of monsoon layer, the ITF latitude, and the rain belt over West Africa (WA), the concept of an interaction between the three has an intuitive appeal since the northern boundary of the moisture flux position determines

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Gang Zhang, Kerry H. Cook, and Edward K. Vizy

Mission (TRMM 3B42) and the Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks (PERSIANN), we conclude that almost all regions have a single diurnal peak, either in the afternoon or at night. The purpose of this paper is to examine the ability of a regional, convection-permitting atmospheric model to reproduce the diurnal cycle of rainfall over West Africa and capture the underlying physical processes. The performance issues of the current generation of GCMs and

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Kerry H. Cook and Edward K. Vizy

reproduce the region's climate with sufficient accuracy to capture the observed distribution of growing-season days over East Africa. The current paper is motivated by projections of large decreases in the number of growing-season days in East Africa for the mid-twenty-first century (2041–60) discussed in Cook and Vizy (2012) . As seen in Fig. 1c , large reductions in growing-season days are projected for eastern Ethiopia, Somalia, southern Kenya, eastern Uganda, and much of Tanzania in these

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Gang Zhang, Kerry H. Cook, and Edward K. Vizy

models are expected to realistically capture the diurnal cycle of rainfall in the contemporary climate. However, previous studies (e.g., Cook and Vizy 2006 ; Dai 2006 ; Xue et al. 2010 ) show that the diurnal cycle of tropical rainfall is poorly simulated by the current generation of general circulation models (GCMs). Even when models produce realistic average rainfall amounts on seasonal time scales, they fail to correctly simulate the diurnal cycle of rainfall (e.g., Dai 2006 ). This deficiency

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Rosalind Cornforth, Douglas J. Parker, Mariane Diop-Kane, Andreas H. Fink, Jean-Philippe Lafore, Arlene Laing, Ernest Afiesimama, Jim Caughey, Aida Diongue-Niang, Abdou Kassimou, Peter Lamb, Benjamin Lamptey, Zilore Mumba, Ifeanyi Nnodu, Jerome Omotosho, Steve Palmer, Patrick Parrish, Leon-Guy Razafindrakoto, Wassila Thiaw, Chris Thorncroft, and Adrian Tompkins

Meteorology of Tropical West Africa: The Forecasters’ Handbook is set to change the way forecasters, researchers, and students learn about tropical meteorology and will serve to drive demand for new forecasting tools. Daily weather patterns directly influence human survival in Africa more so than in any other well-populated continent. Furthermore, West Africa currently exhibits one of the largest population growths on Earth, with many emerging megacities that are prone to urban flooding from

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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

years, the number of spaceborne instruments collecting data available to Earth scientists has grown (e.g., Ungar et al. 2003 ; Friedl et al. 2002 ; Tapley et al. 2004 ). It is now feasible, even routine, to access estimates of precipitation, potential evapotranspiration, land use, land cover, topography, soil moisture, and other variables collected from space in a timely fashion. Moreover, these datasets are often available for free regardless of geopolitical boundaries. Multiple studies have

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

). Part I thus provided the physical basis for understanding the mechanisms of Ethiopian rainfall variability and identifying regional rainfall drivers. The current study builds on that foundation by developing new statistical methods for assessing the predictability of monthly-to-seasonal Ethiopian rainfall on national and local scales, as a step toward an operational seasonal prediction capability for Ethiopia. On interannual time scales, monsoon rainfall variability now is widely recognized as

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Mimi Stith, Alessandra Giannini, John del Corral, Susana Adamo, and Alex de Sherbinin

institutional responses to late-twentieth-century drought The Sahel reached its current prominence in the study of human–environment interactions because of the well-documented environmental crisis that occurred with the abrupt onset and persistence of multiyear drought in the late 1960s ( Glantz 1977 ). Persistent drought led to widespread food insecurity into the 1970s and 1980s, with acute episodes during 1968–73 and 1982–84 causing significant human loss. The climatic shift from wet conditions in the

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