Wintertime Winds and Coastal Sea-Level Fluctuations in the Northeast China Sea. Part I: Observations

Abstract

Abstract Analyses of low-pass filtered coastal sea-level data and geostrophic winds derived from surface pressure charts for the period of 1 December 1980 through 31 March 1981 indicate that the wintertime dynamics in the Northeast China Sea is strongly influenced by the passage of rapidly moving cold fronts from northwest to southeast across the region. Along the west coast of Korea, sea-level fluctuations are highly coherent with the north–south wind in two bands centered, respectively, at about 0.17 and 0.36 cpd, and propagate to the south for the low-frequency band. Removal of the wind-forced component of the sea-level signal yields freely propagating fluctuations in bands centered at about 0.20, 0.34 and 0.50 cpd, that travel northward at approximately the phase speed expected for barotropic Kelvin waves, indicative of a relaxation in the sea-level field following the successive passages of cold fronts. Coherence studies of winds and sea-level differences in the Tsushima Strait indicate a correlation...