Tidal and Residual Currents Observations at the San Matías and San José Gulfs, Northern Patagonia, Argentina

Abstract

Abstract Four current time series, collected at costal locations of the San Matias and San Jose gulfs, Argentina, are analyzed for tidal and residual currents. Tides dominate San Matias Gulf dynamics, accounting for more than 72% of the variance, whereas winds dominate at San Jose Gulf, explaining approximately 70% of the variance. Tides display a dominating semidiurnal regime, in compliance with what is know from the few tidal stations available and numerical simulations. At San Matias, coastal tidal currents speed increases northward, exceeding 0.6 m s−1 at San Antonio Este. Higher order harmonics because of nonlinear interactions are large; in every sampled site, M4 and M6 currents are stronger than the diurnal constituents and have amplitudes around 5% of those from M2. At Las Grutas (San Matias Gulf), simultaneous wind observations were collected. Currents respond almost instantaneously to wind variability in the form of two modes. The first one results from winds blowing along the northwest–southeas...