As temperatures rise, ice sheets and glaciers melt, the warmer ocean takes up more space and other changes cause global mean sea level to rise. This affects coastal communities and coastal habitats such as mudflats, wetlands and rocky intertidal zones. Habitats can erode and become inundated periodically or permanently; and plants, animals, groundwater and other resources are affected by increased salinity and other changes. There is also a great concern for the potential loss of homes, roads and other infrastructure in coastal communities that could have major economic costs.
Global and regional sea level rise projections have been calculated for the West Coast in a recent National Research Council (2012) report (see below). The report projects global sea level rise of 5.3 inches (+/-0.7”) by year 2030; 28 inches (+/-1.25”) by year 2050; and 32.6 inches (+/-4.2”) by 2100.
For the West Coast, a number of local factors need to be taken into account. The most significant is vertical land movement, which in the Pacific Northwest is highly variable, both positive and negative. Some areas along the coast experience uplift that is outpacing global sea level rise (no negative effects) and some areas are experiencing subsidence that adds to global sea level rise (higher negative effects). Records going back to 1870 of the global rate of sea rise are displayed on this NASA website using a combination of tide gauge and satellite data.
Learn more and read about the research that provided the information above by checking out the links below:
Komar, P. D., Allan, J. C., Ruggiero, P. 2011. Sea Level Variations along the U.S. Pacific Northwest Coast: Tectonic and Climate Controls, Journal of Coastal Research27 (5), 808-823, (2011), doi:10.2112/JCOASTRES-D-10-00116.1
National Research Council. 2012. Committee on Sea Level Rise in California, Oregon, and Washington, Sea-Level Rise for the Coasts of California, Oregon, and Washington: Past, Present, and Future
Oregon Climate Assessment Report. 2010. Chapter 6, Impacts of climate change on Oregon’s coasts and estuaries. www.occri.net/ocar
Tebaldi, C., Strauss, B. H., Zervas, C. E. 2012. Modeling sea level rise impacts on storm surges along US coasts, Environ. Res. Lett. 7 (2012), doi:10.1088/1748-9326/7/1/014032
Vermeer, M., Rahmstorf, S., Global sea level linked to global temperature, Proceedings of the National Academy of Sciences (PNAS) 106, 21527-21532 (2009), doi:10.1073/pnas.0907765106