Shelf Waves in the Beaufort Sea in a High-Resolution Ocean Model

Аннотация

The article examines low-frequency oscillations of sea level over the Beaufort Sea shelf simulated in a high-resolution regional configuration of the Massachusetts Institute of Technology general circulation model during 2007–2009 time interval. Using wavelet analysis, we obtained the spatiotemporal characteristics of shelf waves. Dispersion analysis revealed that these are freely propagating shelf waves, which represent one of the relaxation mechanisms of the Beaufort Sea water system, disturbed from a state of equilibrium by external forces, e.g., wind, upwelling, or atmospheric pressure gradients. These waves have periods of 7, 15, 27, and 75 days; wavelengths of 1510, 1300, 1400, and 550 km; and phase speeds of 2.5, 1.0, 0.6, 0.25, and 0.08 m/s. It is demonstrated that these waves can be generated by wind action north of Cape Barrow, whereupon they propagate eastward along the shelf.