[NOAA] One of the costliest and deadliest forces of nature earns a greater global profile this month. The United Nations hopes to reduce harm caused by tsunamis by designating today, November 5th, as the first World Tsunami Awareness Day. The infrequency of tsunamis complicates the public perception about their dangers, but the tide is turning.According to the National Centers for Environmental Information (NCEI), tsunamis took the lives of more than 290,000 million people in the past 100 years. Their elusive nature contributes to their deadly impact. Unlike many natural hazards, the number of tsunamis is low. In the last 100 years, over 100 fatal tsunamis struck coastlines around the globe.
Tsunamis recognize no particular season or time of day, and although most occur in the Pacific, they have occurred in every ocean. To bring greater awareness to the dangerous nature of tsunamis, World Tsunami Awareness Day marks the first worldwide campaign to improve public knowledge and preparedness. Designated by the U.N. General Assembly, the day includes drills, activities, and continued efforts to improve readiness and public responsiveness.[Boat washed ashore in Talcahuano, Chile from the Maule Chile 2010 tsunami. From NOAA]
Caused by undersea disturbances such as earthquakes, volcanic eruptions, landslides, and other causes, tsunamis are a series of waves that are long in length and time and can grow to hundreds of feet high at the coast. They have the capability to overwhelm infrastructure and obliterate manmade and natural environments. Like the village of Hiro-mura, modern day coastal communities are not immune. Waves sometimes travel up to a mile inland, washing away homes, utilities, automobiles, businesses, infrastructure, and causing fatalities.Many places along the U.S. coastline fall in tsunami danger zones. The most destructive tsunamis in the United States and territories have happened along the coasts of Alaska, American Samoa, California, Hawaii, Oregon, Puerto Rico, and Washington. Globally, the deadliest of all was the December 26, 2004, tsunami in the Indian Ocean. It killed an estimated 228,000 people in 15 countries, with Indonesia, Sri Lanka, India, and Thailand hardest-hit. The death toll included 9,000 tourists from many nations. Images of tsunamis reaching land show their chilling nature and destructive capacity. In many ways, tsunamis demonstrate nature’s untameable power. The signs of an oncoming destructive tsunami can be distinguished from ordinary sea conditions. Unusual and rapid fluctuations of the sea, such as receding tides, signal a tsunami wave is approaching. Other tsunami natural warning signs include ground shaking and a roaring sound from the sea. These natural warning signs may not always precede a tsunami, thus tsunami detection systems are needed. [From March 18, 2011, an aerial view of damage to Sukuiso, Japan, a week after a 9.0 magnitude earthquake and subsequent tsunami devastated the area. U.S. Navy photo by Mass Communication Specialist 3rd Class Dylan McCord via NOAA NCEI]