Sea-Level Rise for California, Oregon, and Washington: Present and Future

This talk discusses the results of a NRC study on U.S. west coast sea-level rise, completed in June. The first part of the study deals with global sea level rise, utilizing data generated since the IPCC (2007) report and examining each of the major contributors to sea-level risel: thermal expansion of sea water in response to a warming atmosphere and ice melt from glaciers, ice caps, and ice sheets. Results show that land ice melt is currently the largest contributor to sea level rise. Predictions of global sea level are developed for 2030, 2050, and 2100. Next, regional sea level is determined by including the effects of local vertical land motions, from tectonics, subsidence, and the spatial distribution of ice melt sea level contributions (sea level fingerprinting). Of particular interest is the potential of a Cascadia subduction zone earthquake that could add more than a meter of sea-level rise in minutes in addition to the expected sea level rise. Again, predictions of sea-level rise for the shoreline of the west coast for 2030, 2050, and 2100 are determined. Implications of sea level rise on storminess, and the erosion of beaches, coastal cliffs, and wetlands are discussed as well.