Journal of Physical Oceanography · 1974 · 287 citations · 0 references
Natural SciencesEarth SciencesOceanographyCoastal OceanographyOcean WavesPhysical OceanographyContinental ShelfSea-level ChangeSea-level VariabilitySurface Wave DynamicsBoundary Condition ApproximationLocal Response AnalysisLow-frequency ModelingMeteorological ForcingOcean Response To Atmospheric ForcingOcean Wave ResponsePredictionShelf Wave Dynamics
Atmospheric disturbances generate currents and sea‑level variations of about 0.1 m s⁻¹ and 0.1 m on continental shelves. The study shows that, with meteorological data, sea‑level changes can be calculated and a prediction system is theoretically feasible. A boundary‑layer approximation is applied to the governing equations, yielding a low‑frequency response expressed as a sum of continental shelf wave modes whose amplitudes satisfy a solvable first‑order wave equation. In a worked example, the second mode contributes only 25 % of the first mode’s sea‑level change, while the third mode contributes just 8 %.
Currents [O(0.1 m sec−1)] and sea-level variations [O(0.1 m)] on the continental shelf can be produced when atmospheric disturbances pass by. Since the atmospheric systems have length scales large compared with the width of the shelf, a boundary-layer approximation can be made to the equations governing the local response to these forcing systems. The low-frequency response can be expressed as a sum of modes (continental shelf waves) and the amplitude of each mode is found to satisfy a first-order wave equation which can readily be solved. In a case where some details are worked out, the second mode's contribution to sea-level changes is only 25% of the first mode's and the third mode's contribution only 8%. Thus, given appropriate meteorological information, sea level changes can easily be calculated, and a prediction system is theoretically possible.