Wednesday, March 28, 2007

Sea Level Rise

Most of Atlantic Canada (except Lake Melville, Labrador) has been experiencing a rising sea level for thousands of years due to sinking of the Earth's crust. Sea level rise due to climate change is predicted to be in addition to this process. Climate change impacts sea level through the warming and expansion of oceans and melting of glaciers.

The rate of sea level rise around Newfoundland and Labrador has increased over the last 300 years. The rate of sea level rise is greatest on the Avalon Peninsula (3-5 mm/ year) and decreases further northward.

Rising sea level is primarily a concern for sensitive, low-lying coastal areas. Combined with storm surges, which occur when low pressure weather systems and strong onshore winds raise water levels to a meter above normal, areas that had never experienced flooding before could be at risk for flooding. Rising sea level increases wave action along the coastline leading to increased erosion. Salt water intrusion in groundwater wells and freshwater is another potential impact of sea level rise.

The risk of flooding from sea level rise may be diminished appropriate adaptation strategies. An example of an adaptation is a municipal plan that restricts development on flood plains or low-lying coastal areas based on projections for sea level rise in the area.