Observation of tide from X-band marine radar image sequences

Tide has been monitored by tide-gauge stations and spaceborne radar altimeters. A new method to estimate the characteristics of coastal tide from X-band marine radar image sequences is proposed. The significant wave height (SWH) is firstly retrieved from X-band marine radar image sequence, and then filtered to remove the influences of noises. The main tide period is retrieved by analyzing the spectrum of the time series of filtered SWH. The change rate of the tide elevation can be obtained from the change rate of the amplitude of filtered SWH. The method is validated by comparing with the predictions from an ocean tide model.