Sea Level Rise

The changing environment will have irreversible impacts that cannot altogether be predicted at this time.

Contributors to sea level rise: Thermal expansion Decreases in glaciers and ice caps Losses from polar ice sheets It is expected that: small islands with a lot of coastline will be most vulnerable due to coastal erosion and increased salt content in fresh water sources the ability of many ecosystems to adapt will be exceeded this century even when CO2 emissions are stabilized, sea level rise due to thermal expansion will continue at a rate that will take centuries to decline Land Movement and Sea Level Rise In the Pacific Northwest, land motion has a large impact on relative sea level rise because of the oceanic Juan de Fuca plate moving under the continental North American plate (Geological Survey of Canada). This motion has been noted to offset the rise in sea level in certain locations on the west coast. In contrast, land in the Fraser River Delta is actually dropping 2 to 10 mm per year.

Rising sea level causes coastal erosion resulting in changes for ecosystems, and in land use.

What can we expect?

Projections of relative sea level rise vary between about 75 and 150 cm in western B.C. depending on local land motion. Over the next century the relative rise on the B.C. coast is expected to be 75 cm in Tofino, 100 cm in Vancouver, and 150 cm in the Fraser Delta.

Monitoring and responding to sea level rise will help us adapt to the changes in geography that we face in the next 50 to 100 years. Preparation requires accurate mapping on vertical land motion on a regional and local scale and detailed analysis of local patterns of uplift.