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Deployment of surface buoy
(Shows a boat next to a yellow buoy. A cable goes down to the sea floor and two anchors hold the buoy in place.)

Deployment of tsunameter
(Shows a tsunameter leaving the boat and falling to the sea floor next to the anchored surface buoy.)

Earthquake
(Shows everything shaking.)

Seismographs detect potential seismic activity
(Shows a building labelled JATWC – Joint Australian Tsunami Warning Centre – where the seismographs are located.)

Tsunami
(Shows a wave passing over the tsunameter.)

Detects change in pressure
(Shows sensors on the tsunameter detecting change.)
(Shows a signal passing from the tsunameter to the surface buoy and up to an iridium satellite in the sky. This beams it back to the JATWC building.)