Wave-turbulence separation at a tidal energy site with empirical orthogonal function analysis

Acoustic Doppler current profilers (ADCPs) are the standard tool for measuring tidal currents at stream energy sites; they used to estimate several parameters, including turbulent kinetic (TKE). However, estimates of TKE from ADCPs often swamped by wave action. We surmise that this bias can be detected as a data mode: test this, we present an empirical orthogonal function (EOF) analysis two months ADCP measurements site with significant activity. The results were compared linear theory, using buoy. first mode identified EOF agrees well predicted and resulting decomposition set into components appears realistic. This is possible alone, therefore offers novel widely applicable technique simultaneous assessment turbulence waves highly-energetic sites. method also applied retrospectively historical sets. show improved higher modes, but requires independent measurement determine optimum number modes. • Wave action introduces large biases energy. contributions decoupled statistically. Method shown work sufficiently strong waves. Decoupling achieved extra data.