Why is it incorrect to refer to tsunamis as tidal waves?
At one time the phenomena we now call tsunamis were called tidal waves. However, that tended to cause confusion because in some places a high wave accompanies the change of tide. The size of that wave is known and is predictable. Thus, if an announcement is made that a tidal wave is approaching, a person might expect a 3 meter wave (a 10 foot tall wave). If on the other hand, an announcement is made that a tsunami is approaching, a person might expect a 10 meter high wave (a 33 foot tall wave). Places that have both high tides and tsunamis need to distinguish between the two.
