VOLCANO WATCH: Tsunami Awareness and Chilean Earthquakes

http://bigislandnow.com/2014/04/10/volcano-watch-tsunami-awareness-month-and-chilean-earthquakes/

April is again Tsunami Awareness Month in the State of Hawaii. As in previous years, groups across the state are conducting exercises and other activities to increase awareness of, and preparedness for, tsunami hazards.

On April 1, at the Wailoa Park memorial to the Shinmachi community that was devastated by the May 1960 tsunami, a service was held in memory of tsunami casualties. April 1 also marked the 68^thanniversary of the 1946 tsunami that struck Laupahoehoe and claimed a total of 159 lives in Hawaii.

Near the close of the service, the Civil Defense warning sirens were sounded as part of their monthly test. That morning, the sirens also provided those who attended a moment to pause and reflect.

After the ceremony, people returned to their weekday routines. Just two hours after the siren test however, an ominous alert flashed at the Pacific Tsunami Warning Center (PTWC) ­­– “Earthquake: South America,” underscoring the importance of recognition and preparedness efforts.

To be sure, there have been great advances in the ability to detect and record earthquakes and quickly determine important earthquake information. As significant as these are, even greater improvements have been achieved in telecommunications and rapid distribution of information.

The earthquake alert at PTWC was followed by the creation and dissemination of a stream of emails, text messages, tweets, and web pages relating to this magnitude magnitude 8.2 earthquake that struck the northern coast of Chile, offshore from the city of Iquique, on April 1 at 1:46 p.m., HST. Owing to the availability of data collected in the vicinity of the earthquake, PTWC determined preliminary location and magnitude of the earthquake in less than three minutes following the initial shaking.

In Hawai‘i, we need to be concerned about potential tsunamigenic earthquakes occurring anywhere in the Pacific basin; however, because of past tragic experiences in Hawai‘i, large earthquakes along the Aleutian Islands to the north (where the earthquake occurred and produced the 1946 tsunami) or in Chile (where a magnitude 9.6 earthquake caused the 1960 tsunami) might create a little more anxiety here. The 1960 tsunami earthquake released more than 30 times the energy released by this year’s April 1 earthquake.