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B. Johns

made to the determination of the tidal structure in an elongated channel. Themodel is used to investigate the practicality of the frequently employed depth-integrated technique andconclusions are drawn about the customary bottom stress parameterization inherent in that approach.Additionally, it is shown that the value of the roughness length of the elements at the floor of thechannel is of importance in determining the frictional dissipation in the model and an evaluation is madeof the tidally

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Hisashi Mitsuyasu, Fukuzo Tasai, Toshiko Suhara, Shinjiro Mizuno, Makoto Ohkusu, Tadao Honda, and Kunio Rikiishi

wave forecasting but also for clarifying the funda-mental process of wave generation. In contrast with agreat many studies of the one-dimensional (frequency)spectrum, only a few studies have been made of thetwo-dimensional (directional) spectrum of ocean waves.Particularly, reliable data for estimating directionalspectra of ocean waves are remarkably lacking exceptfor the data reported by Cote et al. (1960), Longuet-Higgins et al. (1963), Ewing (1969), and recently byTyler et al. (1974).Since 1971

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Christopher S. Meinen and Michael J. McPhaden

-Range Weather Forecasts (ECMWF). The ECMWF winds are on a 2.5° by 2.5° grid and are derived from an atmospheric general circulation model that assimilates measurements from many data sources including ship and TAO buoy winds. We processed twice daily ECMWF analyses to monthly means for this study. A third wind dataset was obtained from the blended scatterometer measurements from the ERS-1, ERS-2, and NSCAT satellites (henceforth referred to as SCAT). The SCAT measurements were blended into a weekly

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Fabrice Ardhuin, Aron Roland, Franck Dumas, Anne-Claire Bennis, Alexei Sentchev, Philippe Forget, Judith Wolf, Françoise Girard, Pedro Osuna, and Michel Benoit

currents. For comparison purposes we will only retain the global-steepness parameterization of Bidlot et al. (2005) , because it is used operationally at European Centre for Medium-Range Weather Forecasts (ECMWF) for wave forecasting, and the saturation-based parameterization of Ardhuin et al. (2010) , used operationnally at the National Centers for Environmental Prediction (NCEP) since May 2012. 3. Waves against strong tidal jets In the ocean, currents are never uniform in the cross-stream direction

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Frank Sciremammano Jr.

property is exploited when doing sometypes of time series forecasting (see Box and Jenkins,1970). It must be accounted for in statistical analysesbecause large, spurious correlations can be indicatedwhich are due solely to long time scales .of variationrelative to the length of the data records. [See Green.hut (1978) and the comments by Sciremammano(1979) for an example.] Slowly varying records (longtime scale) need long sampling time to achieveadequate resolution. The computed, raw correlationdoes not

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Ana M. Mancho, Emilio Hernández-García, Des Small, Stephen Wiggins, and Vicente Fernández

; MacKay et al. 1984 ; Wiggins 1992 ) and discussed in the context of rather simple model flows ( Rom-Kedar et al. 1990 ; Beigie et al. 1994 ; Samelson 1992 ; Duan and Wiggins 1996 ), are also at work in this complex and rather realistic ocean flow. A close link between abstract concepts such as material lobes and transported scalar quantities such as temperature or salt is found. More broadly, nonlinear dynamics techniques are shown to be powerful enough to identify the key geometric structures in

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Jean-Michel Brankart and Nadia Pinardi

the others explain the results. Section 2 presents all steps of data treatment preceding the analysis. Section 3 presents the statistical analysis technique used to compute the monthly T, S horizontal maps. The LIW interannual variability is studied by means of empirical orthogonal functions (EOFs). Section 4 presents the primitive equation model, the long-term simulation, and the comparison of modeled versus observed variations. Finally, in section 5 , our hypothesis about the origin

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Jochem Marotzke

and the very short integration time. The general assimilation technique is explored using a very simple model, a linear first-order equation withforcing and damping. The model is unable to provide a dynamical coupling between the forcing and the modelresponse, owing to a mismatch of integration time and adjustment time ~le. Coupling can be enforced in thesimple linear model through a careful choice of weighting factors, a strategy excluded in the C-CM due to thepresence of very fast processes

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D. A. Mitchell, W. J. Teague, M. Wimbush, D. R. Watts, and G. G. Sutyrin

. The vertical profile of temperature and specific volume anomaly can often be inferred from a travel time measurement through the gravest empirical mode (GEM) technique, originally developed by Meinen and Watts (2000) . In order to improve the interpretation of PIES data and separate the eddy variability from the spatially varying seasonal signal that extends through the depth of the shallow JES thermocline, the GEM technique is enhanced by a combined analysis with the U.S. Navy’s Modular Ocean

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The Wamdi Group

useful results for certainclasses of wind fields--and most models considered inthe study had indeed proven their value in an operational frameworkmthe study demonstrated that noneof the existing wave models were applicable for all windfields, and that none were reliable for extreme situationsfor which wave forecasts are often most needed. In the case of second generation wave models, theproblems are largely numerical rather than physical.Techniques for overcoming these difficulties were suggested

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