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Usama M. Anber, Scott E. Giangrande, Leo J. Donner, and Michael P. Jensen

, for the most part, from organized clusters of deep convective clouds. At shorter, intraseasonal, time scales, realistic simulation of the Madden–Julian oscillation (MJO) remains a hurdle in most GCMs. By modifying the convection scheme to have a greater fractional entrainment rate, some models simulate MJO-like disturbances with reasonable spatial and temporal scales (e.g., Bechtold et al. 2008 ; Kim et al. 2011 ). It was demonstrated that with greater entrainment rates, convection organization

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Isabelle Tobin, Sandrine Bony, and Remy Roca

1. Introduction In the tropics, deep convection constitutes the primary mechanism through which water vapor and energy are transported vertically in the troposphere. It is also responsible for a large part of the cloudiness and precipitation. Because deep convective regions are moister and cloudier than dry, subsiding areas, the fractional area of the tropics covered by deep convection is critical for the mean tropical climate and its sensitivity ( Pierrehumbert 1995 ; Larson et al. 1999 ). At

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Usama Anber, Shuguang Wang, and Adam Sobel

deep moist convection. One set of useful studies involves simulations of RCE (e.g., Emanuel 2007 ; Robe and Emanuel 2001 ; Tompkins and Craig 1998 ; Bretherton et al. 2005 ; Muller and Held 2012 ; Popke et al. 2012 ; Wing and Emanuel 2014 ). While RCE has provided many useful insights, it entirely neglects the influences of the large-scale circulation. Another approach is to parameterize the large-scale circulation (e.g., Sobel and Bretherton 2000 ; Mapes 2004 ; Bergman and Sardeshmukh

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Adam H. Sobel and Gilles Bellon

1. Introduction The occurrence and intensity of deep convection are sensitive to the environmental profile of free tropospheric humidity (e.g., Parsons et al. 1994 ; Yoneyama and Fujitani 1995 ; Mapes and Zuidema 1996 ; Derbyshire et al. 2004 ). It is becoming widely recognized that a correct representation of this sensitivity is important for convective parameterization schemes in numerical models. There is evidence that inadequate sensitivity to environmental humidity is at least partly

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Joanna M. Futyan and Anthony D. Del Genio

1. Introduction Deep convective systems and their associated ice cloud anvils dominate the rainfall and cloudiness over much of the Tropics. As well as their importance to the local climate, these systems may influence global cloud feedback through both direct radiative effects and their role in maintaining large-scale circulations and moisture distributions. However, the response of these systems to a climate perturbation is highly uncertain, with numerous, sometimes contradictory, potential

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David M. Schultz

Hohenegger and Stevens (2013) present compelling multiple arguments that indicate that the time scale is much too slow for congestus to precondition or moisten the atmosphere for deep moist convection, that environments with prolonged occurrence of congestus clouds are not more likely to grow into deep moist convection, and that the presence of congestus does not lead to greater probability of deep moist convection. Their intriguing results leave three questions unaddressed, which are raised

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Hector Teitelbaum, Hervé Le Treut, Mohamed Moustaoui, Gustavo C. Cabrera, and Guillermo Ibañez

1. Introduction Deep convection frequently occurs east of the Andes Cordillera, in the northern part of Argentina. From October to March, heavy hail stones that reach the ground can produce severe damage to cultivated land. Such events have particularly large consequences, for example in the Mendoza area, a region famous for its vineyards. In this paper, we study the main dynamical conditions that are required to generate the warm and moist air masses necessary for deep moist convection, and

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Renske Gelderloos, Caroline A. Katsman, and Sybren S. Drijfhout

1. Introduction Labrador Sea Water (LSW) is one of the main mode waters in the North Atlantic Ocean ( Lazier 1973 ; Lazier et al. 2002 ). It is formed in winter by deep convection ( Clarke and Gascard 1983 ; Lab Sea Group 1998 ) and facilitated by the harsh climatic conditions in this region and the regional ocean circulation ( Marshall and Schott 1999 ). It spreads southward and eastward into the North Atlantic Ocean and beyond, where it partly sets the density structure at intermediate

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Richard P. James and Paul M. Markowski

1. Introduction In recent decades numerous studies have examined the sensitivity of deep convection to both thermodynamic and kinematic properties of the larger-scale environment within which the convection exists. Certain key environmental properties have been found to exert strong and predictable influences on the structure and evolution of convection, including vertical wind shear (e.g., Thorpe et al. 1982 ), convective available potential energy (CAPE; e.g., Weisman and

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Fabio D’Andrea, Pierre Gentine, Alan K. Betts, and Benjamin R. Lintner

1. Introduction The representation of deep convection remains a key source of uncertainty, bias, and error in current generation numerical weather prediction and climate models [see, e.g., Arakawa (2004) and references therein]. Over land, a commonly encountered deficiency involves the incorrect phasing of the diurnal cycle of precipitation: most parameterizations used in state-of-the-art general circulation models (GCMs) trigger deep convection too early, generally in phase with the peak in

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