UO earthquake expert testifies on need to enhance early warning capability
UO scientist Douglas Toomey told a House oversight panel today that the Pacific Northwest is "in the window" of geologic time for a catastrophic Cascadia-fault earthquake and that an early warning system is needed to save lives and preserve the region's economic infrastructure.
Toomey, a professor of geophysics in the Department of Geological Sciences, testified before the U.S. House Subcommittee on Energy and Mineral Resources during a session titled "Whole Lotta Shakin': An Examination of America's Earthquake Early Warning System Development and Implementation."
The oversight hearing was an examination of a plan developed by researchers and the U.S. Geological Survey to provide a warning system – a recognized need but not funded in the Obama administration's budget proposal. U.S. Rep. Peter DeFazio, D-Ore., ranking member of the U.S. House Natural Resources Committee, is among signers of a letter in support of a West Coast early warning system.
Toomey, who leads the four-year, $30 million Cascadia Initiative funded by the National Science Foundation, noted that 300 years have passed since the last earthquake in the Cascadia Subduction Zone. Seismologists project that the zone, which runs from Northern California to Canada, is due for a magnitude 9 quake similar to those in Sumatra, Chile and Japan in the last decade.
"The Pacific Northwest is unprepared for a catastrophe of this scale," Toomey said. "FEMA [the Federal Emergency Management Agency] estimates that the direct financial losses would be $60 billion, while the Insurance Bureau of Canada expects losses of approximately $75 billion in Canada."
A big problem, he testified, is that scientists do not understand offshore quake zones as well as those on land. As part of the Cascadia Initiative, hundreds of seismometers are now along the coast, but the current method of retrieving data, by ship once a year, does not offer early warning assistance. "If seafloor cables attached the seismometers," Toomey said, "they could provide real-time, near-field monitoring of the Cascadia Subduction Zone."
The NSF-supported Cascadia and Ocean Observatories Initiatives and the USGS-supported Advanced National Seismic System, Toomey said, provide a foundation for assessing and mitigating the seismic and tsunami hazards in the Pacific Northwest. "As laudable as these efforts are, however, they fall well short of providing society with real-time warnings to take emergency action," he said.
Scientists project that a Cascadia quake will rupture from south to north. An entire onshore-based early warning system, Toomey told the committee, could provide warning of two minutes to Eugene, three minutes for Portland and five minutes for Seattle -- enough time to evacuate schools and public buildings.
An offshore system, he said, would give additional warning time, improve reliability and also allow scientists to detect minor events that occur prior to major shaking. For example, he noted, before the Tohoku, Japan, event there were days and weeks of slow slip activity.
A current obstacle of land monitoring, he warned, is a large gap in the placement of seismic-monitoring stations operated by the Pacific Northwest Seismic Network in southwestern Oregon.
An onshore warning system, Toomey said, is doable with current technology. "The only thing that is missing is the funding to develop this much-needed system," he added. "The opinion of the Pacific Northwest Seismic Network is that once funding is available, a high-performance earthquake early warning system for the West Coast is, at most, five years away."
The UO and the University of Washington have provided seismic monitoring through the Pacific Northwest Seismic Network for more than 20 years. As part of the network, UO faculty and others monitor and maintain a subset of sensors and stations statewide.
— By Jim Barlow, Public Affairs Communications
--
__._,_.___
No comments:
Post a Comment