The island of Newfoundland is unprotected on its eastern seaboard from the open North Atlantic Ocean. This exposes it to hurricanes, major storms and severe winter ice conditions. As climate change progresses, the effects of rises in the sea level and increased intensity and frequency of storms make the coast vulnerable. The NRC's Ocean, Coastal and River Engineering Research Centre and Memorial University researchers and students are developing computer models that could help us determine how best to protect our coast using nature-based solutions. In particular, they are looking for sites that are well-suited to protection by seagrass.
Seagrass grows naturally in coastal areas in Atlantic Canada, and it has been found to be effective at lessening the energy of waves and reducing shoreline erosion. "The idea behind the project is to create a numerical model of waves and storm surge around Newfoundland, both under current conditions and future sea-level conditions," says Mitchel Provan, an engineer at the NRC's Ocean, Coastal and River Engineering Research Centre. "I find it interesting being able to work on a new approach," he says. Then, looking at the wave conditions and water levels, researchers can determine where seagrass would both thrive and offer adequate shoreline protection along the coast.
Students at Memorial University have created a detailed numerical model of the climate and how it is predicted to change for the area. Outputs of the climate model, such as temperature, wind speeds and directions and atmospheric pressure, are being taken to provide the drivers for the wave and storm surge model.
Provan explains that, as the sea levels rise, larger waves can penetrate closer to shore, especially during storm surge events and high tides. But not all sites are right for the cultivation of seagrass, which needs to be covered by water to grow well but not covered so deeply that waves wash right over it. The seagrass also needs to be planted where it won't be wiped out in a big storm.
The students are currently calibrating the model. "Once it's shown that the numerical model can reproduce waves and storm surges around Newfoundland, the model can be used to replicate and better understand those more extreme events and sea level or climate change events,." Says Provan.
He explains that the conventional solution for coastal protection is to line the coastline with rock and concrete. Now, nature-based solutions are offering an alternative. "It's a valuable thing for Canada moving forward because you don't have these big engineered structures cutting off access to the shoreline," he says. "And while these nature-based solutions are still in their infancy, this new approach is ramping up all over the world and will improve local ecosystems."
"I think humans have done enough to take away from the ecosystem, particularly around the coast. And so being able to claw that back a little bit and help improve the ecosystem is important for dealing with climate change, the larger storm events that are coming and the higher water levels. Given the length of Canada's coastline and how much of the population lives near the water, I think coastline protection is a crucial element that needs to be addressed. And if you start with the research now, by the time it starts becoming a serious problem, we would hope to have good solutions and be confident in the performance of these nature-based solutions."