00:00 Tsunamis are devastating natural disasters that can strike without warning, causing widespread destruction and loss of life.

01:41 A tsunami is a series of large waves caused by an underwater displacement of water, often resulting from earthquakes, and is not synonymous with tidal waves.

03:06 A tsunami is defined by its wavelength, which is measured in kilometers, and unlike normal waves, tsunamis come in and keep coming in, growing in height as they approach land due to the displacement of water caused by earthquakes or other underwater events.

04:33 Before a tsunami hits, the sea will often disappear, which is a major warning signal for those in coastal areas, as the water will then come rushing in with great force, tearing down buildings and causing widespread destruction.

05:53 Tsunamis can travel incredibly fast, reaching speeds of up to 500 miles per hour, and the most dangerous ones are those that occur very close to land with little warning for those living closest to the epicenter.

07:18 Megasunamis, which are created by a sudden displacement into water such as a landslide on land or a water impact of a meteorite, differ from regular tsunamis in their formation and are defined by their large wave heights.

08:45 Megasunamis are rare, but regular tsunamis occur several times a year; notable examples of megasunamis include the 1958 event in Latoya Bay, Alaska, the 1963 event in Italy, and the 2015 event in Tan Fjord, Alaska, with wave heights reaching hundreds of meters; if in an area with a tsunami warning, head inland to high ground or seek shelter in a sturdy building, as buildings can collapse from the force of the water; the 2004 Indian Ocean tsunami, which killed almost a quarter of a million people, is unlikely to happen again due to advances in detection and early warning systems.