Atlantic Canada on irreversible path to significant sea level rise

 Canada’s Changing Climate report says Atlantic Canada will have a higher-than-average sea level rise. -
Canada’s Changing Climate report says Atlantic Canada will have a higher-than-average sea level rise. 

A new report on climate change has found that parts of Atlantic Canada will experience higher-than-average sea level rise in the coming decades, leading to more storm surges and flooding, ecosystem and infrastructure damage, and coastline erosion.

And while lowering global emissions can mitigate some of the worst case outcomes, experts say this trajectory cannot be reversed and governments need to also focus on protecting infrastructure and planning for the impacts of these projected rises in at-risk communities.

Tabled on Tuesday, the sweeping report, called Canada’s Changing Climate, was led by Environment and Climate Change Canada and authored by government scientists across a number of departments.

One of the main findings of the report was that scientists have high confidence that Nova Scotia, P.E.I. and parts of New Brunswick and the island of Newfoundland, will experience sea level rise higher than the global average during the coming century.

Thomas James, a research scientist with the Geological Survey of Canada who authored the section of the report that looks at sea level change, said for all possible emission scenarios, global sea levels are expected to rise, and that rise will be more pronounced with higher global carbon emission scenarios.

According to the report, global mean sea level is projected to rise by 28-98 centimetres by the end of the century but, under a high emission scenario, the only area of Canada expected to see between 75 and 100 centimetres is Atlantic Canada.

An illustration included in Canada’s Changing Climate Report, released Tuesday, which shows projected relative sea level changes in the year 2100 for a high emission scenario at 69 coastal locations in Canada and the northern United States.
An illustration included in Canada’s Changing Climate Report, released Tuesday, which shows projected relative sea level changes in the year 2100 for a high emission scenario at 69 coastal locations in Canada and the northern United States.

James said that’s because sea level rise is compounded in the region by something called postglacial rebound.

“In the last ice age, the centre of Canada was loaded with thick ice sheets that were three to four kilometres thick, they pushed down the surface of the Earth, and deep in the Earth the mantle material actually … behaved like very thick molasses, and on the edge of the former ice sheet the land actually rose a bit,” he explained.

“Now that the ice is gone, the centre area that was depressed is now rising and peripheral areas, which includes parts of the Maritimes, that were elevated are now slowly sinking. Where the land is sinking slowly, it adds to the global sea level rise, so projected relative sea level rise is bigger than the global value.”

In places like Halifax, James said, this could mean a 20 centimetre increase in mean sea level rise and a four times increase in flooding by mid-century — in the next two or three decades — even in a low-emissions scenario. In a high emission scenario, the impact could be doubled.

“What we need to do is adapt, and that’s for the (infrastructure) that already exists, and protect, which is for the future — like protecting ecosystems, protecting us from putting ourselves where we shouldn’t be.”

– Nancy Anningson, senior co-ordinator of coastal adaptation, Ecology Action Centre

The report says large impactful events, such as high water levels reached once every 50 years at Halifax in the past, may occur as frequently as every two years by mid-century under the relative sea level rise caused by a high emission scenario.

To make matters worse, James said in some more northern areas, like in the Gulf of Saint Lawrence and along the Labrador coast, sea ice duration is expected to decrease causing less shoreline protection for things like storm surges.

According to data available via sealevelrise.ca, a joint initiative of conservation groups like the Halifax-based Ecology Action Centre and Newfoundland and Labrador Conservation Corps as well as federal and provincial governments and universities, 60 per cent of the population of New Brunswick, 70 per cent of the population of Nova Scotia and 90 per cent of the population of Newfoundland and Labrador live in coastal communities, and no place in P.E.I. is further than 16 kilometres from the coast.

It’s little wonder why people like Nancy Anningson, the Ecology Action Centre’s senior co-ordinator of coastal adaptation, are pushing for governments to start preparing for the inevitable.

“What we need to do is adapt, and that’s for the (infrastructure) that already exists, and protect, which is for the future — like protecting ecosystems, protecting us from putting ourselves where we shouldn’t be.”

In Nova Scotia, where sea level rise is projected to be the highest, a bill called the Coastal Protection Act was tabled in March and aims to legislate some of the items on the protection side such as limiting coastal developments and protecting coastal ecosystems like wetlands and dunes and marshes that buffer storms and protect the coastline.

Anningson said while governments are catching on to the protection piece, there is little being done to adapt homes and infrastructure that are currently in danger.

“The next step is to start to figure that out … and there are options for how to adapt as long as we acknowledge this is happening and prepare,” she said.

Some of those options include things like moving or raising structures, or waterproofing basements.

“We need to get information out to people and make them more aware of how this is impacting them and where the biggest risks are,” Anningson said. “We need to start working on that stuff, because this is happening.”

As for reducing the worst case scenarios presented by sea level rise, James said the only way is to put the entire globe, not just Canada, on a pathway of low carbon emissions.

“That’s what will reduce climate change and reduce the impacts of climate change,” he said. SOURCE

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David Suzuki, prominent environmentalists launch cross-country tour warnings of global crisis

David Suzuki
David Suzuki makes an appearance at United Church on Bloor Street on June 10, 2019.

Some of Canada’s leading environmentalists are trekking across the country to illustrate what they are calling global climate crisis.

Toronto marked the first stop on a seven-city tour for The Leap, a collective of prominent activists who are backing a Green New Deal, an ambitious U.S. plan to curb climate change and transform the economy by investing in clean energy jobs.

The movement is gaining traction among members of the Democratic Party in the United States.

Among those who were touting its virtues in front of a sold out crowd at United Church, located near Tuesday night were author and activist Naomi Klein and environmentalist-turned-broadcaster David Suzuki, who blamed the media for not properly highlighting the perils of planet-wide climate change.

“In May, the United Nations released a study saying we are causing a catastrophic rate of extinction threatening a million species of plants and animals,” Suzuki said. “The next day, Prince Harry and Meghan Markle had a baby and pushed everything out of the news.”

“Fundamental changes are urgent,” he warned, saying consequences to ecosystems, food supplies and economies will be dire by the year 2100 if global temperature increases aren’t capped to within 1.5 degree Celsius above pre-industrial era averages.

His sentiments were echoed by Pam Palmater, who works as a professor, lawyer and aboriginal rights activist.

“What will it take for people to wake up and realize we don’t need to just change things around the edges? Stop using plastic straws, yes! But that won’t save the world. This isn’t about who you vote for. The most irresponsible a citizen can do is vote and then call it a day.”

The next stop on The Leap’s cross country tour is Thursday in Montreal, with appearances scheduled to follow in Ottawa, Halifax, Edmonton, Vancouver and Winnipeg.  MORE

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‘This is a wake-up call’: swift action needed on rising seas, experts say

Waves pound the shore on a closed section of Highway 207 in Lawrencetown, N.S. on Friday, Jan. 5, 2018.Waves pound the shore on a closed section of Highway 207 in Lawrencetown, N.S. on Friday, Jan. 5, 2018. THE CANADIAN PRESS/Andrew Vaughan

Worrying figures released this week on the rising seas in Atlantic Canada should prompt governments and citizens to move more swiftly to protect coastal buildings and vital transport links, say flooding experts.

Blair Feltmate, head of the Intact Centre on Climate Adaptation at the University of Waterloo, said in an interview Friday that projections of 75 centimetres to one metre of relative sea level rise for the East Coast by the end of the century are “a wake up call and a call to arms.”

He was reacting to Chapter 7 of Canada’s Changing Climate Report, which includes a survey of federal science on sea level rise under various emissions scenarios developed by Environment and Climate Change Canada.

Feltmate points to the study’s predictions for quadrupling of flooding along the Halifax waterfront as sea levels rise 20 centimetres over current levels by mid century.

Blair Greenan, a federal oceanographer who oversaw the oceans chapter of the report, said in an interview that without any adaptation measures, flooding during Halifax storms will be noticeable in just a decade as relative sea level goes up about 10 centimetres.

“It will probably have doubled,” he said during an interview. “It is an important point that southern Atlantic Canada is the highest risk area in Canada for sea level rise.”

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https://globalnews.ca/video/embed/3252474/
The federal study also highlights the vulnerability of the Chignecto Isthmus – a low-lying, 20-kilometre band of land which joins Nova Scotia to New Brunswick, said Feltmate.