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Lee-Lueng Fu

solutions for idealized equatorial basin modes, which can be resonantly excited at certain frequencies depending on the size of the basin and the ocean’s stratification. The size of the equatorial Indian Ocean happens to yield resonant frequencies close to a subset of those of the seasonal cycle and its higher-order harmonics. The resonant response of the equatorial Indian Ocean at the semiannual period was demonstrated by a number of modeling studies ( Jensen 1993 ; Han et al. 1999 ). Han et al

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Ichiro Fukumori, Dimitris Menemenlis, and Tong Lee

, respectively. Observed and modeled sea level fluctuations are analyzed in section 4 . The basin-wide sea level oscillation is first identified in section 4a . The effects of buoyancy forcing and winds are analyzed in sections 4b and 4c . In section 4d , a simple analytical model is put forth that describes the basin-wide fluctuation. The relationship between wind- and pressure-driven variability is examined in section 4e . A summary and conclusions are presented in section 5 . 2. Sea level

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Victor Zlotnicki, John Wahr, Ichiro Fukumori, and Yuhe T. Song

Mode index and SSP at five tide gauge stations along the Antarctic coast, corrected for short- and long-period tides, high-pass filtered all data with a cutoff of 100 days −1 to avoid spurious correlations induced by the seasonal cycle ( Chelton 1982 ), and concluded that the strong negative correlation between these two quantities could be explained by a simple model whereby stronger eastward winds increase the equatorward Ekman transport, that is, a divergence of surface water near the

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Manfred Wenzel and Jens Schröter

has a free surface and conserves mass rather than volume. The usefulness of the model is further improved by adding the steric effects explicitly to the original coding. The temporal evolution of the sea surface height ζ is determined as where ζ represents the sea level, H is the depth, P is precipitation, E is evaporation, R is river runoff, T is the temperature, S is salinity, p is the pressure, α = 1/ ρ is the specific volume, and v is the horizontal velocity. This offers

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Claudia Pasquero and Eli Tziperman

used turbulent closures in ocean models are the Mellor–Yamada 2.5-level scheme (MY2.5; Mellor and Yamada 1982 ), which includes a prognostic equation for the kinetic energy of the unresolved scales, and the K -profile parameterization (KPP; Large et al. 1994 ), which includes a nonlocal term in the expression for the turbulent diffusivity in the presence of unstable stratification (convective regime) and is meant to represent the effects of plumes or eddies that traverse large vertical distances

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Felix W. Landerer, Johann H. Jungclaus, and Jochem Marotzke

volume gradually from 3 × 10 4 km 3 to less than 1 × 10 4 km 3 . We give an order of magnitude estimate of the effects of the inferred freshening to the halosteric anomaly in the Arctic Ocean in section 4 . The analysis presented in the following sections is based on annual mean values. Since we are interested in the transient changes under the SRES-A1B scenario, seasonal variability, which is mostly due to air–sea heat and freshwater exchange that affects the upper 100 to 200 m of the water

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D. Roemmich, J. Gilson, R. Davis, P. Sutton, S. Wijffels, and S. Riser

high latitudes, where strengthened westerlies resulted in increased northward Ekman transport, divergence of the surface transport near Antarctica, and acceleration of the Antarctic Circumpolar Current. At middle latitudes around 40°S they noted increases in Ekman convergence, SST, and westward flow as effects of an increased SAM. Our description will correspond to this midlatitude part of their domain, and more specifically, in the South Pacific sector. The present study utilizes a combination of

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Martin Losch and Patrick Heimbach

from 50 m near the surface to 690 m near the bottom. To concentrate on the bottom topography effects, the model is forced with annual means of wind forcing fields ( Trenberth et al. 1990 ) and heat and freshwater fluxes ( Jiang et al. 1999 ) for most experiments. No temperature or salinity relaxation to climatology is applied. The topography is derived from ETOPO2 by horizontal smoothing with an averaging kernel with a radius of 230 km and interpolated to the 4° grid. The only additional editing of

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Dimitris Menemenlis, Ichiro Fukumori, and Tong Lee

effects of nearshore currents, this study finds large contributions from currents offshore of the 284-m isobath and from the along-strait wind setup. This study also finds that the sea level difference is approximately proportional to the wind stress rather than the wind speed. The remainder of this article is organized as follows. Section 2 compares the observations of sea level and winds near Gibraltar Strait. Section 3 lays out a theoretical basis for the wind-driven Atlantic to Mediterranean

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A. Köhl, D. Stammer, and B. Cornuelle

simulation of the observed data. Moreover, Stammer et al. (2004) demonstrated by comparing with satellite-based wind stress estimates the skill of the wind stress corrections in regions away from the energetic boundary currents, which allows us to distinguish between the compensation for model deficiencies and realistic corrections. Figure 5 (bottom) shows the rms model SSH variability. Much of the variability in the boundary currents and their extensions is associated with the seasonal warming

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