As climate change continues to raise sea levels worldwide, the impact on Canada’s coastal communities will be extreme, according to climate scientists.
On Lennox Island off the north shore of Prince Edward Island, residents are seeing their shoreline disappear at a rate twice that of the rest of the Island, so says Adam French, director of the Climate Research Lab the University of Prince Edward Island. “A lot of the most recent science is telling us it could rise as much as three metres during that time,” says Fenech in conversation with the CBC. “Probably in about 50 years, with the three-metre increase, we’d probably see half the island in the water completely.”
The impact on Lennox Island’s First Nations community could be severe, as rising sea levels may cause problems with infrastructure items such as the local water treatment plant and the bridge to the PEI’s mainland. Lennox Island has seen storm surges over the past few years that have flooded the bridge, and French says that the community’s sewage treatment plant is vulnerable due to its position close to the shoreline. “A lot of the water supply for the island comes from ground water, and if you do get a storm surge, it can seep into the well water,” says French.
UPEI’s Climate Research Lab is the author of the award-winning Coastal Impacts Visualization Environment (CLIVE) project, an interactive computer simulation which shows in detail how sea level rise and coastal erosion are expected to affect various regions of PEI. Municipal planners are already taking advantage of CLIVE in helping to prepare communities for the upcoming effects of climate change, says French. “The real message is ‘stop building so darn close to the shoreline,’” says French. “When things like wastewater treatment facilities get flooded, they end up contaminating bays. That can lead to, for example, the closure of a shellfish industry.”
The Climate Lab is currently building CLIVE simulations for use by other communities such as Colchester County, Nova Scotia, and Collingwood, Ontario, and the group is also in discussion with the University of Southern California about a CLIVE modeling of sea level rise and its impact on the shoreline of Los Angeles. “Erosion is not a huge issue there, but they lose a lot of sand on their city beaches, replenishing them for tourism and local recreation,” says French. “The cost of that is huge.”
Global sea level rise is caused by the warming of the oceans (which causes water to expand) and by the melting of glaciers and ice sheets. In the 20th century, sea levels rose faster than in any of the previous 27 centuries, according to a study published in February, and the rate of increase has been charted on the uptick since the 1990s, rising from a previous 0.6 inches per decade to 1.2 inches per decade since 1992.
Predicting the speed and extent of rising oceans is a hot topic for debate, with well-known climate scientist James Hansen recently publishing a study which claims that naturally occurring feedback loops could cause the rate of ice loss from Greenland and Antarctica to double every five to 40 years, creating a multi-metre increase in sea levels in potentially as short a time span as the next 40 to 50 years. Meanwhile, estimates from the U.N.’s Intergovernmental Panel on Climate Change – said to be the consensus projection at the moment – put sea level rises at a more modest one metre by the close of the 21st century.