Fig. 5

Detiding of the Karachi marigram. a November 15 to December 1, 1945. Digitized version of traced marigram (black) is superimposed on tidal curve (light blue) approximated by piecewise fit of cubic polynomials to high waters and low waters—control points that were computed as in Fig. 5 for the days of the tsunami (November 28 and 29) and for two prior outages (November 20 and 23), and were fitted to the traced marigram outside those time windows. Graph of residual shows difference between these black and light blue curves. b As in a, but for November 27–29. c Previously detided curve for part of November 28 from Neetu et al. (2011, p 1613)