Tidal constituents from remote sensing image sequences

The broader question of how many images are needed to obtain tidal constituents from an annual record is also addressed. Using SSH values from a NOAA tide gage station as a surrogate for image-derived SSH values, we progressively decimate a yearlong tide record, calculating its tidal constituents at each level of decimation. We find that that only one image every ten days is needed to retrieve the five largest tidal constituents to within a 10% error.