EOF filter is used to detide an ongoing tsunami record
at a DART buoy.
The first frame in each QuickTime movie shows a section of a DART record containing a historical tsunami (black dots, a mix of 15-min (standard reporting mode) and 1-min (event mode) measurements), a tidal estimate with a low-pass Butterworth filter (cut-off at 3 hours) (red), and a difference of the two used as a reference tsunami signal (bottom pane).
The rest of a movie shows tsunami signal extracted "during an event", while the data are coming in.
To imitate an event situation, a flow of 1-min data starts at a peak of either seismic or tsunamu or trigger pulse signal, whereas a flow of 15-min data is terminated 4 or 6 hours before the start of the 1-min reporting mode.
Top pane: a DART record up to a current moment (black) and a tidal estimate with an EOF filter (red). Middle pane: the difference of the two (tsunami, black) and the reference tsunami signal (cyan). Bottom pane: the difference between the reference and the EOF-filtered tsunami.
Nov. 15, 2006 Kuril Isl. tsunami (6 hour gap in data) recorded at
Jan. 13, 2007 Kuril Isl. tsunami (4 hour gap in data) recorded at
Aug. 15, 2007 Peru tsunami (4 hour gap in data) recorded at