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Carolyn A. Reynolds, Justin G. McLay, James S. Goerss, Efren A. Serra, Daniel Hodyss, and Charles R. Sampson

aspects of the practical application of the ET described in McLay et al. (2008) that can be improved upon. Primarily, given a finite number of ensemble members, the initial ensemble perturbations are too small in the tropics and too large in the midlatitudes, when compared to the analysis error variance estimate produced by the Naval Research Laboratory (NRL) Atmospheric Variational Data Assimilation System (NAVDAS; Daley and Barker 2001 ). McLay et al. (2007) illustrate how an archive of

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Hai Lin, Jacques Derome, and Gilbert Brunet

1. Introduction One of the most important climate signals that has ever been observed is El Niño–Southern Oscillation (ENSO). It has a considerable impact on the atmospheric circulation not only in the Tropics, but also in the middle and high latitudes. ENSO is believed to be responsible for a dominant part of the skill in seasonal weather predictions (e.g., Kumar and Hoerling 1995 ; Shukla et al. 2000 ; Derome et al. 2001 ). Studies aimed at understanding the atmospheric response to ENSO

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Arthur F. Krueger and Jay S. Winston

358 JOURNAL OF THE ATMOSPHERIC SCIENCES VoLu~m31A Comparison of the Flow Over the Tropics During Two Contrasting Circulation Regimes Aa:rrrua F. Kacr~oEa .~o JAY S. W~STONNational Environmentat Satellite Seroic~, NOAA, Hillcrest Heights, Md. 20031(Manuscript received I1 June 1973, in revised form 25 October 1973)ABSTRACT The contrasting circulation and cloudiness over the tropics during two extremes

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Paul W. Miller, Thomas L. Mote, and Craig A. Ramseyer

thermodynamic environments are characterized by greater low-level moisture content, trade-wind inversions, weaker vertical wind shear, and a higher melting level and tropopause. Taken together, these differences serve to alter both the dynamical and microphysical processes active in tropical thunderstorm updrafts compared to their midlatitude counterparts, and diminish the transferability of existing, predominantly midlatitude-centric, convective forecasting techniques to the tropics. For instance, abundant

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Ping Chen, James R. Holton, Alan O'Neill, and Richard Swinbank

3006 JOURNAL OF THE ATMOSPHERIC SCIENCES Vot..51, No. 20Isentropic Mass Exchange between the Tropics and Extratropics in the Stratosphere PING CHEN AND ,[AMES R. HOLTONDepartment of Atmospheric Sciences. University of Washington. Seattle, Washington ALAN O'N-ILLDepartment of Meteorology, University of Reading, Reading, United Kingdom RICHARD SWlNBANKMeteorological Office

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Tsing-Chang Chen

624MONTHLY WEATHER REVIEW VOLUME 113On the Maintenance of Enstrophy in the Tropics during the FGGE Northern Summer T$ING-CHANG CHENDepartment of Earth Science. Iowa State Universio,, ~4mes, IA 50011(Manuscript received 19 April 1984, in final form 27 December 1984)ABSTRACT The wind fields generated by the ECMWF FGGE lll-b analyses at ten mandatory levels were used toexamine the tropical enstrophy budget in the spectral domain

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Sean P. F. Casey, Andrew E. Dessler, and Courtney Schumacher

. (1999) lacked the data to account for the limiting factors of midlevel congestus cloud-top heights. The explanation of congestus cloud-top heights has recently turned to anomalously warm and dry midtropospheric conditions noted by Johnson et al. (1996) . Dry air from aloft in higher latitudes enters the tropics and subsides in long filaments hundreds of kilometers in width. Yoneyama and Parsons (1999) related these layers to Rossby wave breaking and tracked the source back to midlatitude

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P. Goswami and Rameshan K.

must be one that is operative over a wide spectrum of timescales. The most promising candidate seems to be ocean–atmosphere coupling (OAC) as many of these variabilities are now found to be present both in the atmosphere and the ocean. Recent analyses reveal that ocean–atmosphere coupling plays a significant role in a wide spectrum of oceanic and atmospheric variabilities in the Tropics. Following the conceptualization by Bjerknes (1969) , it has long been held that ENSO is an ocean

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L. L. Pan, E. L. Atlas, R. J. Salawitch, S. B. Honomichl, J. F. Bresch, W. J. Randel, E. C. Apel, R. S. Hornbrook, A. J. Weinheimer, D. C. Anderson, S. J. Andrews, S. Baidar, S. P. Beaton, T. L. Campos, L. J. Carpenter, D. Chen, B. Dix, V. Donets, S. R. Hall, T. F. Hanisco, C. R. Homeyer, L. G. Huey, J. B. Jensen, L. Kaser, D. E. Kinnison, T. K. Koenig, J.-F. Lamarque, C. Liu, J. Luo, Z. J. Luo, D. D. Montzka, J. M. Nicely, R. B. Pierce, D. D. Riemer, T. Robinson, P. Romashkin, A. Saiz-Lopez, S. Schauffler, O. Shieh, M. H. Stell, K. Ullmann, G. Vaughan, R. Volkamer, and G. Wolfe

Guam (13.5°N, 144.8°E) with research flights conducted during January and February 2014. The Airborne Tropical Tropopause Experiment (ATTREX) used the high-altitude NASA Global Hawk (GH) to sample chemical and microphysical parameters at altitudes between ∼14 and 18 km [see ATTREX overview by Jensen et al. (2017) , this issue]. The Coordinated Airborne Studies in the Tropics (CAST) experiment used the U.K. FAAM BAe 146 research aircraft to measure a large suite of chemical tracers from the MBL up

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H. L. Kuo

JOURNAL OF 'rHPL ATMO~I-'H!~KIU ~JCIENCP.~5 -OLUMEt3A Two-Layer Model Study of the Combined Barotropic and Barocllnlc Instability in the Tropics H. L. KuoDepart~nent of Geophysical Sciences, The University o.t Chicago, Chicago, IL 60637(Manuscript received 6 Match 1978, in final form 3 July 1978) ABSTRACT The stabilities of shear zone and jet type mean currents with both horizontal and vertical

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