Chart showing the M2 tidal constituent in the oceans, from the TOPEX/Poseidon satellite project.. Colours show tidal amplitudes (in cm). White lines show contours of equal phase, with lags of 1 lunar hour, with arrows showing direction. For a fuller description, see Gerkema <a rel="nofollow" class="external text" href="https://core.ac.uk/download/pdf/80950747.pdf">An Introduction to Tides</a>
Richard D Ray, Goddard Space Flight Center, NASA
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