Disaster Management in Fisheries

7.1.2 Earthquake

One hundred to 200 kilometers off the Peruvian coast, tectonic plates that cover the planet are active. There, the Nazca Plate grinds under and pushes up the South American Plate, releasing energy that sometimes becomes an earthquake.

In the early evening on August 15, an 8.0-magnitude earthquake occurred near the coast of central Peru, about 145 kilometers southeast of Lima, according to the U.S. Geological Survey (USGS). The earthquake killed more than 500 people, injuring 1,600 and left tens of thousands homeless.

The National Oceanic and Atmospheric Administration's (NOAA) Pacific Tsunami Warning Center in Hawaii issued and later cancelled a tsunami warning and watch for the Pacific coast of South and Central America, which experienced small tsunami waves less than a meter high.

Among the seismic stations that helped pinpoint and characterize the major earthquake were five new stations that USGS has installed in the Caribbean over the past two years. The agency plans to install four more seismic stations there by the end of 2007.

"These newer instruments are making available the kind of data that makes a difference when trying to estimate the kind of earthquake and the magnitude," seismologist Walter Mooney, lead coordinator for the USGS Indian Ocean tsunami warning system program, said during an August 16 USINFO interview.

"The correct magnitude probably came significantly faster and more accurately than it would have in 2004," he added.

Another difference since 2004 is the expanded use of deep ocean assessment and reporting of tsunami (DART) buoys, designed by NOAA’s Pacific Marine Environmental Laboratory (PMEL) in Seattle to detect tsunamis as they move across the ocean.

The Peruvian tsunami was detected by a Chilean-owned DART buoy that sent tsunami data to the Pacific Tsunami Warning Center within one hour of tsunami generation. The data were used to provide experimental tsunami forecasts for 13 U.S. ports within two hours of tsunami generation.

“The DART data and forecast were instrumental in the quick cancellation of the warning,” said PMEL Director Eddie Bernard, in an August 17 e-mail. “This is the big difference from 2004 to now. With DART data, tsunami forecasts are now possible. Good forecasts lead to good decisions.”