ABSTRACT
One of the interesting phenomenon that occur at some locations during tsunami events is the withdrawal of the ocean, before the main tsunami waves arrive at that location, which is generally referred to as the initial withdrawal of the ocean (IWO). However, always IWO neither occurs at the same location for every tsunami nor at every location for the same tsunami. Sometimes IWO leads to tragic circumstances because curious people go to the ocean to watch the ocean bottom, which under normal circumstances is never exposed.
