Wetlands & Sea Level Rise
The most reasonable estimates of relative sea level rise in the Chesapeake Bay region over the next century run between 2.3 and 5.2 feet per century. This was the rate used by the Virginia Commission on Climate Change in 2008, based on a report by the Chesapeake Bay Program's Science and Technology Advisory Committee (4mb PDF file). Even the lower end of this rate will adversely impact Virginia’s tidal wetlands: Wetlands Watch estimated that Virginia would lose between 50 and 80% of its tidal wetlands with that rate of sea level rise.
Currently, the best estimates for sea level rise rates are one meter, three feet, over the next century. That is the rate that Delaware, Maryland, and North Carolina (until recently - see article) are using in their coastal planning.
Three feet may not sound like much, but it is a death sentence to the low laying shorelines, dunes and wetlands found within a few feet of sea level. A healthy tidal wetland accumulates enough plant material and sediment to move vertically but our wetlands are under stress, limiting their elevation. With a two-foot + rise, wetlands that can’t keep up must retreat into upland areas.
And when those upland areas are built out, bulkheaded, or hardened, that retreat is blocked and the wetlands will drown in place.
The Center for Coastal Resources Management (CCRM) issued a study in 2009 detailing the impact of climate change on shallow water habitats, confirming these impacts.
These impacts were explained by Dr. Carl Hershner of CCRM in an interview on "What Matters" from May, 2008
, an excerpt of which is below:
A good presentation on tidal wetlands and sea level rise inundation was prepared by the Maryland Chesapeake and Coastal Program and can be viewed HERE
. (6.3 mb .pdf file)
Read other studies on the environmental threats from sea level rise in our region:
"Coastal Sensitivity to Sea Level Rise: A Focus on the Mid-Atlantic Region" - a US Government report discusses the impact of sea level rise on the physical characteristics of the coast on coastal communities and the habitats that depend on them. It examines multiple opportunities for governments and coastal communities to plan for and adapt to rising sea levels.
"Sea Level Rise and Coastal Habitats of the Chesapeake Bay" - The National Wildlife Federation's excellent study on how sea level rise will affect the Chesapeake Bay.
"Climate Change and the Chesapeake Bay" - (3.8 mb .pdf download) - A report by the federal government's Chesapeake Bay Program on the state of scientific understanding of climate change impacts on the Chesapeake Bay and recommendations for addressing those impacts.
Fish and Wildlife Service Website on Marsh Modeling has lots of good resources.
More about efforts to adapt to sea level rise
Read more about
Sea Level Rise and You