These houses in North Rustico, P.E.I., were flattened and uprooted by the wind from Hurricane Fiona.
Climate change could come between Nova Scotia and New Brunswick, with national consequences.
Projections show that sea-level rise will eventually sever the main highway and rail routes that connect Nova Scotia — and the shipping port of Halifax — to New Brunswick and the rest of Canada.
This is no fringe projection. It’s the basis of voluminous research and government reports on municipal, provincial and federal levels. There is no consensus on how to meet the challenge, though all agree that dikes built by Acadian farmers in the 1700s — and that have for so long protected farms, towns and major infrastructure — are destined to be swamped.
“The actual permanent breaching of the dikes and the permanent putting of the area under water is a long way off,” says David Kogon, the mayor of Amherst, N.S. “What could happen tomorrow is if you get a big storm at high tide and you get this giant storm surge, we can have a major flood. How much damage would be done by that flood would be in the billions of dollars. So we’re trying to protect from the short-term flood and then the permanent flood. It’s vitally important that a mitigation plan be developed and implemented.”
Ground zero is the Isthmus of Chignecto, the strip of land between the Bay of Fundy and the Northumberland Strait that connects Nova Scotia and New Brunswick. The isthmus is only 24 kilometres wide at its narrowest point, and much of it is below sea level.
The nature of the isthmus has long been known by Mi’kmaq people, who named it “Siknikt,” or drainage place. The approximately 300-year-old dikes near Amherst, N.S., and Sackville, not far inside the New Brunswick border, have effectively kept out salt water pushed by storms and by the world’s highest tides, which race up the Bay of Fundy.
“The dikes are protecting the highway, the CN Rail line, as well as other infrastructure, such as sewage lagoons,” says Sabine Dietz, executive director at CLIMAtlantic and a town councillor in Sackville. “Part of Sackville is behind it, part of Amherst is behind it, other areas down the coast are behind those dikes. So when you get sea level rise and storm surges, those dikes can be either destroyed, breached or overtopped.
“Simply, the entire infrastructure in the back is not sufficiently protected to withstand what we know is going to happen with climate change.”
Tens of millions of dollars worth of goods move through those corridors daily, which is a national concern.
“If you lose even one or two days of transportation across the corridor,” Dietz says, “you’re going to run into supply-chain problems, and we know during COVID what happens when the supply chain is interrupted. We run into empty shelves.”
During an interview, Kogon shares a starkly illustrative photograph that shows storm-surge waters a few inches from the crest of the highest dike — atop which lie the rail lines, with the Trans-Canada Highway not far behind it.
Holding back the waters will be expensive. The federal and provincial governments are issuing reports and studying options, and cost estimates range from $175 million to $300 million, Kogon says, not including decades of ongoing maintenance as water levels inexorably rise.
“It’s not just Amherst that’s in big trouble,” the mayor says. “The entire province of Nova Scotia is in big trouble, because how do you get goods from the port of Halifax to the rest of Canada?”
His most urgent fear is a surge pushed by a major storm at high tide in the Bay of Fundy, which would combine Mother Nature’s punches. “Even if it might ultimately recede, it’s still going to be a very damaging situation,” Kogon says.
Hurricane Fiona was not that storm — though it caused damage in Amherst and was the worst Atlantic Canada has seen in living memory. (Ironically, this feature on climate change pushed the deadline when key sources became unavailable due to power outages.)
In Port aux Basques, N.L., houses were washed out to sea. The picturesque fishing village of Stanley Bridge, P.E.I., was all but destroyed. Along the shorelines of New Brunswick and P.E.I., ecologically fragile dunes were washed away, as were the boardwalks, roads and pathways built to allow us to enjoy the dunes without causing damage. And everywhere, hundreds of thousands of trees were downed, some torn clear out of the ground. Two weeks after the storm, tens of thousands of people still had no power, many schools remained closed, and years of cleanup and repair lay ahead.
These are examples of the challenges to come, as the seas that surround the region rise and warm, and change in less obvious ways. Memorial University oceanography professor Brad de Young says oceans are likely losing their capacity to absorb much of the CO2 that we pump into the atmosphere.
The water is also more acidic and holds less oxygen, and circulation patterns are affected by freshwater flows from melting ice and shifting patterns of precipitation. All of this reduces the oceans’ capacity to help regulate atmospheric temperatures and cool the planet.
“It would accentuate the storm patterns in the North Atlantic, which shift those in a way that it’s hard to predict, because it would do it in ways that we haven’t really ever seen precisely,” de Young says.
This also affects where fish and other sea creatures live, as they are sensitive to temperature and will migrate northward as waters warm. It may help explain why Atlantic cod stocks have never rebounded as expected.
“There’s growing suspicion that the character of these ecosystems has begun to shift and [they] don’t have the resilience they [once] had,” he says.
Land-based species will also migrate as climate changes, as some familiar trees and plants will become less common, while less familiar species will grow into the new conditions. It’s as if climate change is affecting — to use a recent movie title — Everything Everywhere All at Once.
Réal Daigle, a retired meteorologist who worked with Environment Canada for 37 years and now volunteers at CLIMAtlantic, notes how these systems are intertwined. That’s why the region is seeing more 30-plus Celsius days, and other extremes.
“We expect to see more frequent episodes of high rainfall or high precipitation events,” Daigle says, “the reason for that being that warmer temperatures generate more water vapour in the atmosphere.”
Such changes are affecting how infrastructure and buildings are built, says Blair Greenan, a research scientist with the Department of Fisheries and Oceans in Halifax. Sea levels rise, waters warm, and there’s less sea ice to protect coastlines from increasingly severe winter weather.
“Coastal locations will be starting to experience winter storms that they wouldn’t have necessarily experienced in the past, and that will put additional pressure on coastal erosion and the infrastructure,” Greenan says.
Researchers are developing online tools to predict sea level rise in precise locations, to help designers and engineers who build docks, bridges and other infrastructure. New requirements on water-side development are now imposed by legislation such as Nova Scotia’s Coastal Protection Act.
“If you are building a cottage or home along the coast of Nova Scotia, you’re going to have to meet certain criteria that take into account climate change expectations,” Greenan says.
de Young says people ignore the changes at their peril.
“All of us have to be prepared to figure out how to deal with them, because they’re going to happen, whether we like it or not.... All of the forecasts that have been made so far have been optimistic. Unfortunately, they haven’t been pessimistic enough.”
Tools for local climate forecasts
- CLIMAtlantic site with many resources
- Regional perspectives and other reports
- Sea level projections by community