Assessment of the physical disturbance of the northern European Continental shelf seabed by waves and currents

摘要: Natural seabed disturbance was quantified by estimating the number of days in a year that movement occurred due to waves and currents. Disturbance over gravel substrates based on concept critical threshold for bed movement. For mud assessed basis failure under extreme hydrodynamic stress. sand beds frequency calculated reference predicted occurrence small scale bedforms using established relationships ripple megaripple height. The method applied northern European Continental Shelf (48°N 58.5°N 10°W 10°E) modelled annual wave current forcing with temporal resolution one hour spatial approximately 11 km. Highest levels areas high tidal stress where dune/megaripple type were shallow regions exposed large fetch. However, detailed distribution showed complex relationship between water depth, stress, fetch grain size. An assessment uncertainty results made use simple Monte Carlo approach. In most locations this indicated values suggesting present predictive need improvement if assessments natural are be confidence. Nevertheless give broad understanding location intensity physical ability compare relative different regions. This has applications management human impacts have context underlying disturbance. Recommendations given further research might help decrease prediction.