different regions. For the dominant M2 tide, the differences of
tidal amplitudes decrease as the lengths of the time periods
increase. There is one exception in the seventh time period,
where the differences of the M2 tidal amplitude are small, but
the differences of the S2, O1, and K1 tidal amplitudes are too
large to be applicable in this time period. For the M2, S2, O1,
and K1 tides, the amplitude differences in the tenth time period
are applicable. Therefore, the minimum observation time of the
radar would be about 1200–1300 h (i.e., about two months) to
derive satisfactory tidal information