11-12+~+Prachi&Kim+Quake+Report+(TWS)

**Tsunami Warning System (TWS)** **by Prachi & Kim**

What is a TWS? A Tsunami Warning System (TWS) is used to detect tsunamis in advance and warns people about them to prevent loss of life and damage. It consists of two important components: a network of sensors to detect tsunamis and a communications structure to issue timely alarms to allow evacuation in coastal areas. There are two distinct types of tsunami warning systems: international and regional. While operating, seismic alerts are used to set up the warnings. Then, data observed from sea level height are used to verify the existence of a tsunami.

How does a TWS work? To assume there is a tsunami, there has to be a major undersea earthquake/landslide with a magnitude > 7.0. When there is one of these earthquakes, they use Seismic Measuring Equipment, Tide/Sea-Level Instruments, and NOAA Tsunami Detection Buoys. After detection, Tsunami Warning Centers Alaska and Hawaii are informed about the tsunami. Before deciding if there is a tsunami or not, the Centers issue warnings in Areas close to the Earthquake. They then decided whether there is a tsunami or not. If there is a tsunami, they continue informing the people through bulletins, tsunami advisories, watches, and warnings Then, then National Weather Service Costal Offices activate EAS for Tsunami Watches and Warnings via NOAA Weather Radio. They then inform the State and Local Emergency Management Officials, and to those with NOAA Weather Radio Receivers in homes, businesses, schools, etc, and All-Hazard Alert Broadcast (AHAB). If no tsunami, people are told there is no tsunami with the same methods. The Local Emergency Management Officials activate EAS for Evacuation, for those with NOAA Weather Radio Recievers. They also tell people through TV, Radio, and Cable TV.

The Pacific TWS The Tsunami Warning System (TWS) in the Pacific, comprised of 26 participating international [|Member States], has the functions of monitoring seismological and tidal stations throughout the Pacific Basin to evaluate potentially Tsunamigenic earthquakes and disseminating tsunami warning information. The Pacific Tsunami Warning Center (PTWC) is the operational center of the Pacific TWS. Located near Honolulu, Hawaii, PTWC provides tsunami warning information to national authorities in the Pacific Basin. As part of an international cooperative effort to save lives and protect property, the [|National Oceanic and Atmospheric Administration]'s (NOAA) [|National Weather Service] operates two Tsunami warning centers. The Pacific Tsunami Warning Center in Ewa Beach, Hawaii, serves as the regional Tsunami Warning Center for Hawaii and as a national/international warning center for tsunamis that pose a Pacific-wide threat. This international warning effort became a formal arrangement in 1965 when PTWC assumed the international warning responsibilities of the Pacific Tsunami Warning System (PTWS). The objective of the PTWS is to detect, locate, and determine the magnitude of potentially Tsunamigenic earthquakes occurring in the Pacific Basin or its immediate margins. If the location and magnitude of an earthquake meet the known criteria for generation of a tsunami, a tsunami warning is issued to warn of an imminent tsunami hazard. A tsunami watch with additional predicted tsunami arrival times is issued for a geographic area defined by the distance the tsunami could travel in a subsequent time period.