Characteristics of Tide Variation/Change along the China Coast

摘要

Based on the observing data from 1980 to 2016 of 24 tide gauges, thelong term tide variation/change along the China coast are investigated.Results show that the mean sea levels, M2 constituent amplitudes, meantidal ranges, mean high tide levels, mean low tide levels along theChina coast show rising trends, at the average rate of 0.32 cm/year,0.09 cm/year, 0.31 cm/year, 0.51 cm/year, 0.19 cm/year, respectively.From the northern Yellow Sea to Hangzhou Bay, the mean tidal rangesincrease significantly, with the values of 0.50-1.30 cm/year. The meantidal ranges along China coast have obvious 18.61 year cycle variation,which the amplitude is more than 20 cm on the Beibu Gulf coast.