Impact of dissipation on the energy spectrum of experimental turbulence of gravity surface waves

We discuss the impact of dissipation on the development of the energy spectrum in wave turbulence of gravity surface waves with emphasis on the effect of surface contamination. We performed experiments in the Coriolis facility, a 13-meter diameter wave tank, and ensured careful cleaning of surface contamination, which poses a significant challenge as the surface of water exceeds 100 m². The observations indicate that under the cleanest conditions, the frequency energy spectrum reveals a power law decay extending up to the gravity capillary crossover at 14 Hz, where the spectral exponent increases with the forcing strength but decreases with surface contamination. Although this exponent for the clean water is slightly higher than previously reported in literature, it remains significantly below the predictions made by the Weak Turbulence Theory. By analyzing length and time scales, we illustrate that weak turbulence cannot be anticipated at frequencies exceeding 3 Hz. Additionally, we observe stereoscopic 4-wave interactions in this context, contributing to a deeper understanding of the turbulence characteristics in gravity surface waves.