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Chun Li, Lixin Wu, and Shang-Ping Xie

) footprinting ( Vimont et al. 2001 , 2003 ; Alexander et al. 2010 ), was identified as important for communicating the extratropical forcing to the equatorial Pacific ( Wu and Li 2007 ; Ma and Wu 2011 ; Li and Wu 2012 ). The ventilation of cold water from the midlatitude winter mixed layer by the shallow overturning circulation maintains the thermocline in the equatorial Pacific ( McCreary and Lu 1994 ). The present study explores this extratropical-to-tropical teleconnection via the ventilated

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Zhengyu Liu

1. Introduction Recent observations have revealed an important aspect of interannual to decadal extratropical thermocline variability, which is that the sea surface height (SSH) anomaly propagates predominantly westward at all latitudes ( Jacobs et al. 1994 ; Chelton and Schlax 1996 ), while a substantial part of the thermocline temperature variability follows the gyre circulation ( Deser et al. 1996 ; Zhang and Levitus 1997 ; White and Cayan 1997 ). This complexity of thermocline

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David Halpern and Ming Ji

100m-thick mixed layer depth, the mixed-layer temperature, and the depth-averaged temperature below the thermocline were similar in both data products. Considerable differences occurred in the representation of the 15 -25-C thermocline, such as the depth-averaged temperatures above and below the 20-C isotherm, the east-westslope of the 20-C isotherm, and a 1000-km-wide depression. The longitudinal-averaged root-mean-square difference between the hindcast and observed depths of the center of the

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Eli Tziperman

modelis determined from the air-sea heat fluxes, using the integral constraint and a parameterization of the mixingprocesses in layer models. A two gyre mid-depth circulation is found, driven by the cross-isopycnal diffusivevelocities and affected by the variations in the depth of the main thermocline above it. The bottom circulationin both models is similar to that of the Stommel-Arons model. Air-sea heat fluxes affect the deep buoyancy-driven flows not by direct cooling or heating, but through

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Lin Chen, Tim Li, and Yongqiang Yu

results (see Fig. 4 in Yeh et al. 2009 ). The decrease of the equatorial-mean thermocline is consistent with the projected weakening of the Walker circulation under global warming ( Vecchi and Soden 2007 ; DiNezio et al. 2010 , 2013 ). Yet, the model ENSO amplitude changes exhibit a great diversity among the CMIP3 and CMIP5 models. An interesting common feature in Fig. 16 is that maximum shoaling appears near the date line. Given that ENSO amplitude is primarily controlled by the anomalous and

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Zhengye Liu

AUGUST 1996 L I U 1633Thermocline Variability in Different Dynamic Regions ZHENGYU LIUDepartment of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison, Madison, Wisconsin(Manuscript received 20 May 1994, in final form 4 March 1996)ABSTRACT The response of thermocline circulation to a variable wind forcing is investigated with quasigeostrophicmodels

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Timour Radko and John Marshall

. 2a ) also varies along the path of the ACC, being significantly larger in the Atlantic–Indian sector. In this paper we will argue that the spatially nonuniform forcing leads to downstream variation of the thermocline depth and stratification of the ACC [see observations of Sun and Watts (2002) ] and modulates the strength of the upper cell of the meridional overturning circulation. This study attempts to explain the three-dimensional time-mean structure of the ACC and the associated pattern of

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A. Timmermann, S-I. An, U. Krebs, and H. Goosse

; Schmittner et al. 2003 ; Stocker and Johnsen 2003 ). 5. Global seiching The thermohaline circulation transports relatively cold water into the deep ocean. This cold water upwells into the thermocline as a result of mixing and entrainment processes. This balance can be disrupted by a freshwater-induced halt of North Atlantic Deep Water formation. Eventually, the thermocline will deepen in the world oceans because of the reduced supply of cold water from below. This new equilibrium state is partly

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Tianming Li

a simple model of ENSO must incorporate both components of the thermocline depth variation. The physical mechanism behind this stationary SST mode involves two essential types of feedback processes, as illustrated in Fig. 13 . In the left side of this schematic diagram, it depicts a positive feedback cycle. Suppose we start from an initial phase of the El Niño, say, a weak warming in the eastern equatorial Pacific. In response to the SST forcing, the atmospheric east–west circulation, the

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R. M. Samelson

solutions of a closed-basin, single-hemisphere, planetary geostrophic circulation model when κ υ is of order 10 −5 m s −2 . They find that for these small values of κ υ , the subtropical thermocline is composed of two distinct components, an adiabatic “ventilated” thermocline ( Luyten et al. 1983 ) near the surface and an intrinsically diffusive “internal boundary layer” thermocline ( Salmon 1990 ) at the base of the wind-driven motion. Downward diffusion of heat through the internal boundary layer

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