Acehtsunami

A tsunami can be generate by any disturbance that displace a huge water mass from its equilibrium position. In the case of earthquake-generated tsunamis, the water column is anxious by the uplift of the sea floor. Submarine landslide, which frequently accompany large earthquakes, as well as collapse of volcanic edifices, can also concern the overlying water column as sediment and rock droop downslope and are redistributed across the sea floor. Similarly, a violent underwater volcanic eruption can create an impulsive force that uplifts the water column and generate a tsunami. Conversely, underwater landslides and cosmic-body impacts concern the water from above, as momentum from falling wreckage is transferred to the water into which the debris falls. Gernerally tsuna-mis generated from these mechanism, unlike the Pacific-wide tsunamis caused by some earthquakes, dissipate quickly and sometimes affect coastlines distant from the source area. What happens to a tsunami as it approach land?

As a tsunami leaves the deep water of the open ocean and travels into the shallower water next to the coast, it transforms. If you read the “How do tsunamis differ from other water waves?” section, you exposed that a tsunami travels at a speed that is interrelated to the water depth — hence, as the water depth decrease, the tsunami slows.The tsunami’s energy flux, which is depends on the both its wave speed and wave height, remains nearly invariable. As a result, as the tsunami’s speed diminish as it travels into shallower water, its height grows. Because of this shoaling effect, a tsunami, imperceptible at sea, may grow to be numerous meters or more in height near the coast. When it finally reaches the coast, a tsunami may appear as a rapidly rising or falling tide, a series of breaking waves, or even a bore.