The spectra of point measurements of currents: their features and their interpretation

Abstract

Differences in the speed or direction of a harmonic component of the current between ebb and flood, cause a transfer of spectral energy from one tidal band to the others. Cyclic changes in the speed or direction of a component between large and small tides, induce a leakage to neighbouring frequencies. Transient fluctuations, even in a perfectly isotropic flow, have the same effects. As a consequence, the spectral estimates of point measurements of current are not independent. © Taylor & Francis Group, LLC.