Chilean tsunami was first real scale test of the UNESCO/IOC Pacific Tsunami Warning System and enabled emergency evacuations
By Peter Koltermann, posted on March 4th, 2010 in Articles, Disasters, Earth Observation, Technology
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: “This 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.”
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.
NASA Daily Image
Remnant of a Supernova
Vital clues about the devastating ends to the lives of massive stars can be found by studying the aftermath of their explosions. In its more than twelve years of science operations, NASA's Chandra X-ray Observatory has studied many of these supernova remnants sprinkled across the galaxy. The latest example of this important investigation is Chandra's new image of the supernova remnant known as G350.1-0.3. This stellar debris field is located some 14,700 light years from the Earth toward the center of the Milky Way. Evidence from Chandra and from ESA's XMM-Newton telescope suggest that a compact object within G350.1+0.3 may be the dense core of the star that exploded. The position of this likely neutron star, seen by the arrow pointing to "neutron star" in the inset image, is well away from the center of the X-ray emission. If the supernova explosion occurred near the center of the X-ray emission then the neutron star must have received a powerful kick in the supernova explosion. Data suggest this supernova remnant, as it appears in the image, is 600 and 1,200 years old. If the estimated location of the explosion is correct, this means the neutron star has been moving at a speed of at least 3 million miles per hour since the explosion. Another intriguing aspect of G350.1-0.3 is its unusual shape. Many supernova remnants are nearly circular, but G350.1-0.3 is strikingly asymmetrical as seen in the Chandra data in this image (gold). Infrared data from NASA's Spitzer Space Telescope (light blue) also trace the morphology found by Chandra. Astronomers think that this bizarre shape is due to stellar debris field expanding into a nearby cloud of cold molecular gas. The age of 600-1,200 years puts the explosion that created G350.1-0.3 in the same time frame as other famous supernovas that formed the Crab and SN 1006 supernova remnants. However, it is unlikely that anyone on Earth would have seen the explosion because of the obscuring gas and dust that lies along our line of sight to the remnant. These results appeared in the April 10, 2011 issue of The Astrophysical Journal. Image Credits: X-ray: NASA/CXC/SAO/I. Lovchinsky et al; IR: NASA/JPL-Caltech