The Tsunami Makes Landfall

  • As a tsunami approaches land, the wavelength and period begins to shorten.
  • The tsunami also experiences a decrease in velocity, as the velocity of a tsunami (v) is equal to the square root of the acceleration of gravity (g) times the water depth (d). v = (g*d)^1/2
  • Because energy must be conserved, the decrease in wavelength, period, and velocity results in a very large increase in the amplitude, A.
  • Here are some satellite images of the recent tsunami in SE Asia that killed 300,000.
  • The bottom image shows this beach in Sri Lanka early last year, almost a year before the tsunami.
  • The top image shows the still large waves coming onto the beach and further inland, as well as some of the destruction from the wave.