Map shows where climate change to hit

Warns of rising waves, shoreline destruction

HALIFAX — 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 by Gavin Manson, a coastal geoscientist at the Bedford Institute of Oceanography, has taken into account factors like the disappearance of sea ice, rising waves and the makeup of the shoreline.

His Halifax office 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 during an interview from his Halifax office.

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 map-makers 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.