One of dozens of new Geoscan maps by Gavin Manson. (Screenshot/Black Press Media files)

Mapping of Canadian coasts showing where climate change to hit hardest this century

The expectation of rising sea levels has already been documented this year

A federal government geoscientist has developed fresh maps of coastlines showing where flooding and erosion caused by climate change are likely to inflict maximum damage this century.

The mapping effort led by Gavin Manson has taken into account factors like the disappearance of sea ice, rising waves and the makeup of the shoreline.

The latest version of the CanCoast map has combined six key factors to create visual ratings of ”coastal sensitivity” on the three oceans.

Manson said in an interview Wednesday that when you start to consider how wave height rises due to a lack of sea ice or the slope of the shore, it can make a major difference in erosion and flooding.

“It includes a whole lot more information on factors that affect the physical sensitivity of Canada’s coasts,” he said from the Geological Survey of Canada office at the Bedford Institute of Oceanography in Halifax.

The expectation of rising sea levels has already been documented in the Changing Climate Report Ottawa released in April for large portions of Atlantic Canada, the Beaufort Sea, the Fraser River lowlands and northern British Columbia.

In parts of Atlantic Canada where coastal land is sinking as seas rise, the ocean is predicted to be an average of between 75 centimetres to one metre higher by the end of the century — increasing flood risk during storms.

However, Manson points out that quantifying coastal sensitivity takes the analysis further.

The nature of the shoreline — whether it’s beach, gravel or a hard rocky shore — is part of the mix of six variables the geological mapmakers have scored.

Another factor now included in the maps is how the melting of ice in the ground beneath permafrost leaves coasts susceptible to more erosion.

As the ground sinks, the oceans gain in energy, tearing away at the shore. “In the 2090s, there’s much less in the way of sea ice, and there’s more waves,” said Manson.

The researcher says the areas of highest sensitivity are on the northern coasts facing the Beaufort Sea, where bright red colours on the maps signal the elevated risk.

“Things are getting much worse in that area …. It’s one of the areas with the highest increase in sensitivity, and it extends further east into the Arctic archipelago than we would have expected.”

Factors such as melting ground ice and loose materials along the shore are key factors along the coast facing the Arctic Ocean, he adds.

Parts of Hudson Bay are also in the red zone, as are portions of southeastern Cape Breton and tiny Sable Island, hundreds of kilometres off Nova Scotia’s coast.

In the case of Cape Breton, the factors that raise sensitivity include the likelihood of reduced ice on the inland Bras d’Or lakes, which would result in more tidal action against the shorelines.

The mapping data is publicly available for downloading and study on a service called Geoscan.

Manson says the CanCoast maps are being used by all levels of government, as well as coastal engineers and industry consultants.

The Canadian Press

Like us on Facebook and follow us on Twitter.

Just Posted

LRCA Concerts in the Park series presents: Beatlemania Unplugged

This will be the final Concerts in the Park event of the summer

Arts on the Avenue turns 21 this weekend

1st Avenue will have a weekend full of arts on display Saturday evening and Sunday afternoon

Ladysmith gallery hosts Island Living Art Show

Nanaimo Arts Council exhibition opens at the Waterfront Gallery on Aug. 24

Striking Western Forest Products workers could lose benefits in September

Union, forest company at odds over Vancouver Island benefit payments as strike enters third month

Nanaimo Ladysmith education support workers’ deal ratified

CUPE Local 606, Nanaimo school district and bargaining agent ratify deal, which runs till June 2022

B.C. sockeye returns drop as official calls 2019 ‘extremely challenging’

Federal government says officials are seeing the same thing off Alaska and Washington state

Groups ready campaign to help young voters identify ‘fake news’ in election

The media literacy campaign to focus on identifying misinformation and suspicious sources online

Big rally in northern B.C. draws attention to continuing lumber crisis

Mayor Joan Atkinson says about 400 workers have been directly affected by the closure of the Canfor mill

Orangeville Northmen take Minto Cup at Langley Events Centre

Swept best-of-five series 3-0 over Victoria Shamrocks

Expanded support to help B.C. youth from care attend university still falling short

Inadequate support, limited awareness and eligibility restrictions some of the existing challenges

Ethnic media aim to help maintain boost in voting by new Canadians

Statistics Canada says new Canadians made up about one-fifth of the voting population in 2016

UPDATE: Crown cross-examines B.C. father accused of killing daughters

Andrew Berry is charged in the deaths of six-year-old Chloe and four-year-old Aubrey in 2017

Dog attacked by river otters, Penticton owner says

Marie Fletcher says her dog was pulled underwater by four river otters in the Penticton Channel

BC SPCA overwhelmed with cats, kittens needing homes

Large number of cruelty investigations, plus normal ‘kitten season’ to blame

Most Read