Many people acted heroically in the aftermath of Hurricane Katrina. The Coast Guard, for instance, rescued some 34,000 people in New Orleans alone, and many ordinary citizens commandeered boats, offered food and shelter, and did whatever else they could to help their neighbors.
Tidal waves, or tides, are a predictable, com-mon occurrence along coastal communities, generated by forces beyond Earthâthe gravitational pull of the sun and moon. However, tsunamis are not predictable. They are often generated by earth-quakes, volcanic activity, and slope failure.idal waves, or tides, are a predictable, com-mon occurrence along coastal communities, generated by forces beyond Earthâthe gravitational pull of the sun and moon. However, tsunamis are not predictable. They are often generated by earth-quakes, volcanic activity, and slope failure.
A tsunami carries an enormous amount of energy that is spread over a large volume of water in the deep sea. However, when a tsunami reaches shallow water, such as a coastline, the energy is concentrated into a smaller volume and the wave's power overwhelms whatever is in its path.sunami, also known as seismic sea waves, are caused by sudden changes in the seafloor, generally earthquakes and more rarely large landslides. Tsunami are sometimes mistakenly called tidal waves, but they are not caused by tidal action.