“Tsunamis”

by Caleb, KE0FOE

As we continue with our series covering JetStream, The National Weather Service’s new Online School for Weather, the topic this time is: Tsunamis.

Sometimes called a tidal wave or a seismic sea wave, a tsunami is a series of waves in an ocean or lake caused by the displacement of a large volume of water.

Large earthquakes, volcanic eruptions and other underwater displacements are the most common causes of tsunamis.

Did you know that the speed of a tsunami depends on the depth of the water it’s traveling through? The deeper the water the faster the tsunami travels. In the deep ocean, tsunamis can travel more than 500 miles per hour. Because its wavelength can be hundreds of miles, a tsunami is barely noticeable in the deep ocean and is seldom more than three feet high. As a tsunami reaches shallower water near land, it slows down, its wavelength decreases, and its waves grow in height (or amplitude).

A network of Deep-ocean Assessment and Reporting of Tsunami systems (or DART systems) provide for the early detection of tsunamis in the deep ocean. DART systems detect passing tsunamis by sensing pressure changes at the bottom of the ocean. The U.S. portion of DART, part of a larger international network, consists of 39 DART systems located throughout the Pacific and Atlantic Oceans, the Gulf of Mexico, and the Caribbean Sea.

There are a lot of interesting facts about Remote Sensing that you and your family can learn about on the National Weather Service’s new Online School for Weather called JetStream. Visit their website: weather.gov/jetstream