| Summary: | From the position data of 23 drifters over the four years period, 1982 to 1985, the upper layer kinematics of the Northeast Pacific were investigated. The focus of this study was upon the topographic influence, wind forcing, and Rossby waves. The notions of homogeneity and stationarity were applied to both the Eulerian and Lagrangian analysis. A new computational scheme was proposed and tested in order to explicitly take into account the Lagrangian characteristics of the drifter data. The Eulerian analysis showed that the spatial and temporal distributions of the mean current and the mean wind stress were in good agreement. Three of the four eddy kinetic energy maxima found in the region geographically corresponded to topographic features. Also the velocity field of this region appeared to be strongly inhomogeneous, non-stationary, and anisotropic. The results from the Lagrangian analysis showed that the spectral slope for the periods shorter than 5 days followed the -2 law, and suggested that the direct wind forcing was a dominant mechanism for those periods. The spectrum of the eddy component of the velocity appeared to be white for the periods longer than 10 days. The results showed that the linear Rossby waves were not dominant mechanism for upper layer dynamics of this region. The rotary spectra illustrated some evidence of the rotational preference of the cyclonic over anti-cyclonic motions at a period of 10 days. The new scheme provided meaningful information about the eddy component of the velocity. Science, Faculty of Earth, Ocean and Atmospheric Sciences, Department of Graduate
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