World Tsunami Awareness Day
5 November, 2021
Tsunamis are giant ocean waves caused by earthquakes or volcanic eruptions under the sea. As the waves travel inland (sometimes at the speed of a jet plane), they get higher and higher as the depth of the ocean decreases. Though rare, tsunamis can be extremely deadly. The Indian Ocean tsunami (December 2004), for example, caused an estimated 227,000 deaths across 14 countries, with Indonesia, Sri Lanka, India and Thailand hardest-hit. In 2011, the Pacific Ocean Tōhoku earthquake and tsunami in the Pacific Ocean led to 20,000 death and the costliest disaster to date ($360 billion). Tsunami warning systems (TWS) are used to detect tsunamis (sensors) in advance and to issue the warnings through communications infrastructure to prevent loss of life and damage to property. International systems are in the Pacific Ocean, Chile, the Indian Ocean, the North Eastern Atlantic, the Mediterranean and Connected Seas and the Caribbean. Japan also has a regional warning system. World Tsunami Awareness Day is to encourage the development of national and community-level, local disaster risk reduction strategies to save more lives against disasters, a primary goal of Sendai Framework and much-needed given rapid urbanization and growing tourism in tsunami-prone regions putting ever-more people in harm’s way.