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Yuko M. Okumura, David Schneider, Clara Deser, and Rob Wilson

atmospheric model simulations is also analyzed to investigate mechanisms of the teleconnections. We then extend the analysis back to the nineteenth century by using a network of coral and other proxy records from the tropics to test if the knowledge obtained from the analyses of ice core and instrumental data holds true for the past two centuries. The paper is organized as follows. Section 2 describes the ice core and various observational and tropical proxy data used in this study. Section 3 analyzes

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Chuntao Liu

by using continuity test of nonzero 3-hourly rainfall data on each 0.25° × 0.25° grid point. The duration and total rain amount for the events lasting longer than 12 h are summarized. Then their contributions to the total 3B42 rainfall on each 0.25° × 0.25° grid are calculated. 3. Results Mean annual rainfall over TRMM PR observation area (35°S–35°N), tropics (20°S–20°N), and subtropics (35°–20°S and 35°–20°N) from 12 yr of monthly TRMM PR (3A25) and TMI (3A12) retrievals are listed in Table 1

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Peter Vogel, Peter Knippertz, Andreas H. Fink, Andreas Schlueter, and Tilmann Gneiting

more than 10 years ( Haiden et al. 2018 ). A region generally characterized by low forecast skill and high uncertainty is the tropical belt. Haiden et al. (2012) note that 1-day precipitation forecasts at low latitudes have skill similar to 6-day forecasts in the extratropics. Little progress has been made also for free-tropospheric winds in the tropics ( Haiden et al. 2018 ). For variables with large forecast uncertainty, ensemble prediction is of particular importance, even for short ranges

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Daniel J. Vimont

1. Introduction Coupled ocean and atmosphere variations in the tropics involve variations that can generally (though oversimply) be classified as “zonal modes” [e.g. the El Niño–Southern Oscillation (ENSO) phenomenon, or the so-called Atlantic Niño] or “meridional modes” ( Servain et al. 1999 ; Chiang and Vimont 2004 ). A major difference between the two classifications is the physical mechanism that acts to destabilize the mode and hence allows the mode to emerge as a dominant pattern of

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R. B. Smith, P. Schafer, D. J. Kirshbaum, and E. Regina

(2006) , and Rotunno and Houze (2007) , among others], but almost all these studies have been in midlatitudes. A common element of previous studies is that orographic precipitation events were forced, either by a weather disturbance that is already precipitating, (e.g., frontal cyclone, squall line, easterly wave, or hurricane) or by the diurnal cycle of solar heating. We have two objectives: (i) to examine the physics of orographic precipitation in the tropics and (ii) to identify a location with

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Baode Chen, Wen-wen Tung, and Michio Yanai

1. Introduction The perturbation kinetic energy (PKE) is extensively used to measure and study transient wave activity in the tropics (e.g., Webster and Chang 1988 ; Arkin and Webster 1985 ; Chen and Yanai 2000 ; Yanai et al. 2000 ). Murakami and Unninayar (1977) showed that the region of maximum PKE along the equator in January and February of 1971 was located in the vicinity of the equatorial westerlies. Using National Meteorological Center (NMC) operational tropical objective analyses

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Daniel J. Kirshbaum and Ronald B. Smith

). Orography also triggers moist convection by forcing conditionally unstable air to rise over a mountain massif, which is commonly observed in midlatitutes along the west coast of North America (e.g., Kirshbaum and Durran 2005 ), the southern Andes ( Smith and Evans 2007 ), and the Cévennes Vivarais region of France (e.g., Anquetin et al. 2003 ), among other locations. This mechanism also operates in the tropics when trade wind flow encounters mountainous terrain, which can occur along a continental

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Claire Henocq, Jacqueline Boutin, Gilles Reverdin, François Petitcolin, Sabine Arnault, and Philippe Lattes

parameter for the detection via statistical methods of the salinity differences between surface L-band radiometer measurements and in situ measurements resulting from rainfall. However, more than 75% of vertical salinity differences comes from 13 fixed positions in the tropics (TAO/TRITON and PIRATA moorings), mainly located at 95°W. More measurements above 5 m are urgently needed to extend and improve this work. This paper focuses on vertical salinity differences between 1 and 10 m. In the case of a

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Kenneth P. Bowman, Cameron R. Homeyer, and Dalon G. Stone

1. Introduction Precipitation is a key parameter of the earth’s weather and climate. The release of latent heat by condensation is one of the most important drivers of the global atmospheric circulation. Latent heat release is particularly important in the tropics, where the majority of the earth’s precipitation falls. Accurate measurement of precipitation is important for a number of scientific and societal applications, but it is a technically challenging problem, in part because of the

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Tomonori Sato, Hiroaki Miura, Masaki Satoh, Yukari N. Takayabu, and Yuqing Wang

1. Introduction Convective heating is extremely important for the maintenance of global-scale atmospheric circulation. The diurnal cycle of precipitation is a prominent mode in the tropical convective systems; thus, it has often been a target of intensive observations in the tropics ( Houze et al. 1981 ; Skinner and Tapper 1994 ; Mapes et al. 2003a , b ; Zuidema 2003 ; Mori et al. 2004 ). The spaceborne observation established by the Tropical Rainfall Measuring Mission (TRMM) satellite has

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