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Christopher E. Doughty, Scott R. Loarie, and Christopher B. Field

1. Introduction Several modeling studies have indicated that changes in surface energy budgets may affect the movement of the intertropical convergence zone (ITCZ), the region of convection between the two cells of the Hadley circulation. An early study found that increasing albedo north of the ITCZ from 14% to 35% decreased rainfall during the wet season in the Sahel by 40% because the ITCZ shifted several degrees to the south ( Charney 1975 ). More recently, large-scale simulated

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Tobias Bischoff and Tapio Schneider

1. Introduction The bulk of the tropical precipitation falls in the intertropical convergence zone (ITCZ), a band of convective clouds in the tropics that migrates meridionally on seasonal and longer time scales. In the zonal mean, precipitation has one maximum that migrates from the Northern Hemisphere tropics in boreal summer to the Southern Hemisphere tropics in boreal winter. Locally, however, the precipitation can have more than one maximum in a given sector of longitudes. For example

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Rosana Nieto Ferreira and Wayne H. Schubert

1. Introduction Climatologically, about 80% of all the tropical cyclones on the globe form near or within the ITCZ (intertropical convergence zone; Gray 1979 ). This motivates searching for mechanisms that favor tropical cyclogenesis within the context of ITCZ dynamics. In satellite images, the ITCZ is sometimes observed to undulate, forming cloud patterns that resemble inverted Vs ( Frank 1969 ). At times, such an undulating ITCZ breaks down into several tropical disturbances ( Agee 1972

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Chidong Zhang, David S. Nolan, Christopher D. Thorncroft, and Hanh Nguyen

, although not responsible for its existence. Nolan et al. (2007) proposed that the primary mechanism for the SMC associated with the eastern Pacific ITCZ is a local response to regional gradients of surface temperature and surface pressure, when deep convection is absent. Typically in the ascent regions of the ITCZ surface temperatures are high and surface pressures are low, whereas the opposite is true in the nearby descent regions over the equatorial cold tongue and subtropics. Increased thickness

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Chia-chi Wang and Gudrun Magnusdottir

1. Introduction The intertropical convergence zone (ITCZ) is a zonal belt of rather low pressure located in the Tropics where there is low-level convergence, and cloudiness and precipitation are prevalent. The ITCZ has been observed to undulate and break down into a series of disturbances on satellite images (e.g., Agee 1972 ; Thompson and Miller 1976 ; Hack et al. 1989 ). Some of the disturbances may intensify and grow into tropical cyclones, while others dissipate. After the produced

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Duane E. Waliser and Catherine Gautier

2162 JOURNAL OF CLIMATE VOLUME6A Satellite-derived Climatology of the ITCZ DUANE E. WALISERScripps Institution of Oceanography. University of California at San Diego, La Jolla, California CATHERINE GAUTIEREarth Space Research Group, University of California at Santa Barbara, Santa Barbara, California(Manuscript received 25

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Paul E. Ciesielski, Richard H. Johnson, Wayne H. Schubert, and James H. Ruppert Jr.

location of peak amplitude and diurnal variation, and the LT of peak anomalous subsidence). Note that for TOGA COARE the diurnal characteristics listed here are for convectively disturbed periods. Observational studies of intertropical convergence zone (ITCZ) convection over the oceans have generally used satellite data and reanalysis products to characterize its behavior. For example, Waliser and Gautier (1993) used two decades of global infrared and visible satellite products to document the

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Alex O. Gonzalez, Christopher J. Slocum, Richard K. Taft, and Wayne H. Schubert

1. Introduction Figure 1 is a GOES visible–infrared blended image of the Pacific Ocean on 11 March 2015, a day when there were twin tropical cyclones in the west and a double intertropical convergence zone (ITCZ) in the east. A striking feature of this image, and many other similar images, is the narrowness of the double ITCZ bands and, hence, the narrowness of the rising parts of the Hadley circulation. The purpose of this paper is to better understand the boundary layer dynamics associated

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Guojun Gu and Chidong Zhang

1. Introduction Explaining the intertropical convergence zone (ITCZ) remains a challenge. Various theories of the ITCZ have been proposed. They can generally be categorized into two groups. In the first group, the intensity and location of the ITCZ are thought to be closely related to the sea surface temperature (SST) (e.g., Pike 1971 ; Xie and Philander 1994 ; Philander et al. 1996 ). The second group of theories focus on atmospheric internal dynamics. Some of them emphasize only zonally

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Ori Adam, Tobias Bischoff, and Tapio Schneider

1. Introduction The intertropical convergence zone (ITCZ) is a band of deep convective clouds, located at the rising branch of the tropical meridional overturning (Hadley) circulation ( Fig. 1 ), where near-surface meridional mass fluxes vanish. Since the Hadley circulation transports energy away from the ITCZ and dominates the tropical energy transport, column-integrated energy fluxes also vanish and diverge near the ITCZ, forming an atmospheric energy flux equator (EFE) (e.g., Neelin and

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