Observed and modelled tidal currents in the New Zealand region

Abstract

Tidal currents derived from current meter measurements are compared with the output from a barotropic tidal model of the New Zealand region. For the semi‐diurnal constituents there was very good agreement for the M₂ tide and good agreement for the S₂ tide. For the diurnal constituents (K_l, O_l) it was found that as the amplitude of the constituents decreased so did both the model/observation agreement and the accuracy of the observed tidal ellipse parameters. Consequently it was not possible to decide whether differences arose through shortcomings in the model or in the data. However, the overall performance of the model as a prognostic tool for ocean tidal current simulation appears to be good.

Keywords:

• tidal currents
• numerical model
• current measurements
• tidal ellipses