West Coast Damage May Presage Future Climate Change Effects

The effects of the El Niño winter of 2009-2010 on the shoreline of the US West Coast may be an indicator of what could occur as climate change continues, says a team of researchers. If that's the case, substantial, costly damage is on tap, and communities need to plan for and fund ways to adapt.

The team found that, for the California coast during that time, wave energy at representative locations was 20% greater than average, and average shoreline erosion was up 36% (and 75-80% in some locations). That led to damage such as erosion of 200-350 feet in some locations, and several destroyed roads.

For Oregon and Washington, both the energy and erosion were generally lower, though some areas were hard-hit.

The data indicate that wave energy and erosion vary substantially year-to-year, and that the amount of damage seen in the winter of 2009-2010 will almost certainly not be an annual occurrence. But many climate change models indicate the conditions that set the stage for the 2009-2010 damage will become more frequent.

The study was published in Geophysical Research Letters on July 9, 2011. The researchers were from the US Geological Survey, the Oregon Department of Geology and Mineral Industries, Washington State Department of Ecology, University of California, Santa Cruz, Oregon State University, and Scripps Institution of Oceanography.

• "The Impact of the 2009-10 El Niño Modoki on U.S. West Coast Beaches," by Patrick L. Bernard, et al.: release. For a copy of the full study [doi:10.1029/2011GL047707], contact Paul Laustsen, 650-329-4046.