NOAA’s Simulation Tool Prepares Oregon Coastal Towns for Tsunamis and Floods

December 10, 2008

NOAA scientists have created four high-resolution digital elevation models, or DEMs, of Oregon’s coastline that simulate deadly tsunamis and floods. These models will help emergency managers develop life-saving plans for communities in those locations.

The DEMs were developed by NOAA’s National Geophysical Data Center and the Cooperative Institute for Research in Environmental Science, both based in Boulder, Colo. The surface-relief models cover the Oregon coastal area from Port Orford to the Columbia River, including the communities of Coos Bay, Newport, Lincoln City, Seaside and Astoria.

The DEMs are detailed coastal relief models constructed from near-shore seafloor depth and land elevation data. They provide a framework that allows scientists to forecast the magnitude and extent of coastal flooding caused by a tsunami or storm surge with greater accuracy. Since 2006, scientists have created 28 DEMs of U.S. coastal areas and an additional 45 DEMs are planned for the future.

“Creating the DEMs is part of NOAA’s effort to help local emergency managers determine which parts of their communities are most vulnerable to tsunami waves and coastal flooding. This allows them to dedicate their warning and response resources more efficiently and effectively,” said Lisa Taylor, NOAA’s NGDC project manager.

The coastal DEMs are part of the U.S. Tsunami Forecast and Warning System. The new Oregon DEMs will support efforts by the Oregon Deptment of Geology and Mineral Industry to map tsunami evacuation zones. Once these DEMs were finished, NOAA’s Pacific Marine Environmental Laboratory in Seattle incorporated them into distant tsunami model scenarios. These scenarios simulate offshore earthquakes far from Oregon, the resulting tsunami that travels across the Pacific Ocean, and the potential flooding impacts when the tsunami reaches the coast. With this information, the NOAA Tsunami Warning Centers can issue more accurate flooding forecasts if an earthquake triggers an actual tsunami.

In addition to threats from distant tsunamis, Oregon faces other hazards from an active undersea fault zone capable of creating less frequent, but possibly much larger, more devastating local tsunamis that will arrive at the coast quickly. The Oregon Department of Geology and Mineral Industries and the Oregon Office of Emergency Management (DOGAMI) assess tsunami hazards, delineate evacuation zones, and promote tsunami preparedness. The new models will help local emergency officials decide whether to issue population evacuations when a tsunami threatens.

NOAA, along with its federal and state partners in the National Tsunami Hazard Mitigation Program, is implementing the Tsunami Warning and Education Act. This law authorizes and strengthens tsunami detection, forecast, warning, and mitigation. Working together, NOAA, the Oregon Department of Geology and other state and federal partners deliver accurate information to coastal communities to foster tsunami preparedness.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.