Very low fre-quency rip current pulsations during high-energy wave conditions on a meso-macro tidal beach

Very Low Frequency (VLF) rip current pulsation investigations are still poorly documented in the literature. In this paper, we analyse data acquired during an in-situ field experiment on Truc Vert beach, on the Aquitanian coast. This beach was exposed to high energy wave conditions during a spring tide cycle and has high tidal range and gentle slope. VLF motions were observed within the surf zone, with a characteristic frequency of 6 10-4 Hz which corresponds to a 27 minute period. These VLF motions were associated with high velocity. This paper shows that the VLF velocity pulsations were larger in the inner surf zone and increased with increasing offshore wave energy. We found that the significant wave height and the velocity evolved in-phase. These results are in good agreement with Callaghan et al. 2004. This paper also suggests that wave groups might have generated these VLF pulsations