Recent Observations of Tides and Tidal Currents from the Northeastern Bering Sea Shelf

摘要

Tide and tidal current observations from the Northeastern Bering Sea Shelf and a comparison of these observations with theory and numerical models are reported in this memorandum. Pressure observations (November 1981 - August 1982) at seven stations show that the diurnal tides dominate the outer shelf. The diurnal amplitudes (maximum of 38 cm for K1 and 26 cm for 01 at the shelfbreak) decrease exponentially inshore from the shelfbreak at a rate consistent with subinertial Sverdrup waves. The phase lags of the diurnal tides vary little (ranging from 322 degrees G to 359 degrees G for the K1 tide) over the shelf. The semidiurnal amplitudes (maximum of 23 cm for M2 at the shelfbreak) change considerably between stations; on the outer shelf there is some influence of a semidiurnal amphidromic system off Cape Navarin. The phase lags of the semidiurnal tides are earliest at the shelfbreak (87 degrees G for M2) and increase toward the east and north. Numerical models reproduce the general features of the observed tides and tidal currents.