Energy propagation pattern of the 27 February 2010 tsunami calculated with MOST forecast model. Filled colors show maximum computed tsunami amplitude in cm during 24 hours of wave propagation. Black contours show computed tsunami arrival time. Credit NOAA/PMEL/Center for Tsunami Research.
The near-real time sea level monitoring system registered the tsunami on Galapagos (1.0 m in Santa Cruz) to Marquise Islands (1.8 m) and from Malibu (1.4 m) to Valparaiso (1.3 m), from Hiva oa Marquesas (1,29 m) to Hanasaki, Hokkaidao, Japan (0.82 m). Worst hit was the area around Talcahuano, Chile with a 2.34 m.
The Pacific Tsunami Warning System (PTWS) enabled emergency response agencies to warn locals about the risk of tsunami and order evacuations. This is the first real ocean-wide test of a system that was put in place nearly 50 years ago by UNESCO’s Member States through its Intergovernmental Oceanographic Commission (IOC).
Peter Koltermann, Head of IOC’s Tsunami Unit, said: ÛÏThis tsunami is another distressing example of our vulnerability at the coasts to natural disasters. We need to further enhance greater vigilance and preparedness. High-risk coastal communities, where there is very little time, maybe minutes, for populations to receive any warning, have too be strengthened by urgently continuing to develop and implement evacuation measures.Û
The Pacific Tsunami Warning Center in Hawaii, USA relayed and shared the following timeline: The major tsunami off Concepcion, Chile on Feb 27, 06:34 UTC had a magnitude of 8.8 Mw. It issued a regional warning at 06:46. The first sea level measurements at Valparaiso with 1.3 m and Talcahuano with 2.3 m confirmed a tsunami had been generated. PTWC revised and extended the affected region at 09:47. At 10:45 UTC the PTWC warned of a Pacific wide tsunami and subsequent hourly messages expanded the warning to several areas in the Pacific Ocean. Every hour the system coordinated by UNESCO/IOC and operated by national agencies kept updating the established tsunami warning focal points and media accessing the system.
The Pacific Tsunami Warning System (PTWS) was established when a 9.5 magnitude earthquake on May 22, 1960 off Chile on the Pacific Rim generated a tsunami heavily affecting populations from Hilo in Hawaii to the Sanriku coast of Japan. PTWS has operated since 1965 under the mandate of UNESCO/IOC. In the aftermath of the Indian Ocean tsunami on Dec 26, 2004, building on this Pacific experience, UNESCO/IOC established similar systems for the Indian Ocean, the Caribbean and the seas around Europe to ensure a global cover for tsunami hazards.