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.
Tsunamis occur after an earthquake. The earthquake can occur under a city (ex. The New Madrid Missouri fault line; or the Los Angeles area's fault lines), but many occur on the ocean or sea floor.n average, two tsunamis occur per year. Approximately every 15  years a destructive, ocean-wide tsunami occurs. Tsunami's occur  when an earthquake causes a significant ver â¦ tical deformation of the  seafloor.