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Guest Opinion: Earthquake warning system funding is vital Sunday Jun 4, 2017 at 12:01 AM By Eric Dittmer There have been several news articles lately at the state and national levels about the potential loss of federal funding for efforts to expand ShakeAlert, the Earthquake Early Warning System in Oregon and other Western states. What is ShakeAlert and why is it important? Scientists and policymakers are excited about developing an early warning system because it represents a proven, proactive step toward earthquake hazard reduction. Up to now, we on the West Coast only realize an earthquake is occurring when we feel the shaking and wonder how big it will be as we Drop, Cover, and Hold On. Hopefully we have thought about this ahead of time and have a plan for survival. What if we had 30 seconds or more warning that an earthquake has occurred off our coast and damaging seismic waves are coming? How is this done? The concept is simple: Earthquake waves travel very slowly compared to the monitoring system that tracks activity. An earthquake releases stress all at once in the form of seismic waves inside the Earth. Two types of waves are released during an earthquake — key to an early warning system — each traveling at a different speed. The faster “P” waves spread out from the earthquake source (focus) but don’t produce strong shaking. The slower “S” waves also spread out from the same focus, but can produce strong shaking, making them more destructive and dangerous to life and property. In comparison, the data from a real-time monitoring system moves at the speed of light. Real-time seismic monitors stand by to actively search for the P-waves. The EEW system can use this search to provide warning about arrival of the S-waves. Typical speeds for “P” waves are around six kilometers (about four miles) per second, and “S” waves around half that speed. The farther away from the earthquake focus, the more time there is between the arrival of the two waves, and hence, the greater amount of warning time. The closer a seismic monitor is to an earthquake, the quicker it can determine the location and size of the earthquake. The most serious earthquake we are expecting is one originating along the Cascadia Subduction Zone that lies offshore and spans over 600 miles from northern California to southern Canada. Generally, the longer the fault, the larger the earthquake potential. Research on the Cascadia Subduction Zone indicates that more than 40 Magnitude 8 or greater earthquakes have occurred over the past 10,000 years at irregular intervals of 200 to 400 years apart. The last one was January 26, 1700. We are in the window of recurrence for another major event. Jackson County is about 100 miles (160 km) east of the Cascadia Subduction Zone. This distance equates to a minimum of 30 seconds of advanced warning of strong shaking; if rupture begins in northern Cascadia, the early warning could be minutes ahead. An early warning system would be able to detect a “P” wave at the coast and automatically transmit data to a processing center which would relay the information to emergency communication centers for distribution. The ShakeAlert Project is supervised by the U.S. Geological Survey and facilitated by the Pacific Northwest Seismic Network, a cooperative seismic network operated by the University of Washington and the University of Oregon. Coordination with the Oregon Department of Geology and Mineral Industries is helping to increase the number of seismic monitoring stations in Oregon, which lags behind Washington and California in station counts. The ShakeAlert project is also working with local agencies and officials to establish a “pilot” level program in our region because of our unique geologic setting and challenges of our dispersed rural populations. The “pilot” designation would help us refine the communication technology and carry out simulations. What could we do with 30 seconds' warning? People could find the safest places to drop/cover/hold, classrooms could be alerted in time for students to assume safe locations before the ground shakes under them, firehouse doors could be opened, generators started, doctors could stabilize patients, drivers warned to avoid dangerous locations like the viaduct in Medford, elevators could be programmed to stop at the next floor and open the doors, and the list goes on. The USGS estimated the cost at $38 million to implement ShakeAlert, and the $16 million cost for annual maintenance, while not insignificant, is a very small amount compared trillions of dollars proposed in the total budget. Consider the benefits. The ShakeAlert Project can save lives and reduce hazards. It deserves full support at the national, state and local levels wherever there is the potential for damaging earthquakes. ShakeAlert has the support of our West Coast elected officials. You can contact officials in Washington, D.C., to offer your support as well. — Eric Dittmer, Southern Oregon University professor emeritus of environmental studies, promotes earthquake awareness and preparation in southwest Oregon.