Large tidal currents near Bear Island and related tidal energy losses from the North Atlantic

Abstract

Independent series of current meter measurements between northern Norway and Bear Island (19°E, 74 1 2 ° N ) by MAFF Fisheries Laboratory, Lowestoft in 1972 and the Norwegian River and Harbour Laboratory in 1978 both show a ten-fold increase in diurnal tidal currents near Bear Island. The increase appears to be due partly to excitation of a topographic mode of natural frequency less than the tidal constituent K1. Part of the increase is also due simply to the shallower water near Bear Island and is shared by the semi-diurnal tidal currents. Tidal energy fluxes out of the Norwegian Sea total about 5 × 10 10 W between Norway and Bear Island and 6 × 10 10 W between Bear Island and Greenland, in contrast with the observational estimate 7 × 10 10 W entering the Norwegian Sea between Scotland and Iceland.