Abstract:
Field observations were performed at an embayed beachto investigate infragravity
(IG) wave (0.005-0.04 Hz) dynamics. Offshore short-wave conditions measured by
the Cabo Sillero buoy (323 m depth) were characterized by a mean significant
wave height of 0.9 m and a mean peak wave period of 9 s. Analysis of field
observations demonstrate that for this embayed beach two IG wave peaks can be
detected (0.01 and 0.025 Hz). The IG wave band can be separated in two frequency
bands due to the different wave propagation characteristics (0.005-0.02 and
0.02-0.04 Hz). The bound wave generation mechanism was identified based on a
negative correlation between the short-wave envelope and the IG wave elevation
for a time lag of 5 s. The phase-lag evolution of the IG wave increasingly lags
behind the short-wave envelope shorewards.
