Coastal Erosion in Atlantic Canada PDF

**Coastal Erosion in Atlantic Canada** https://thestarfish.ca/journal/2024/03/coastal-erosion-in-atlantic-canada by [[Sierra Christodoulou]](https://thestarfish.ca/members/sierra-christodoulou) in [[Science and The Environment]](https://thestarfish.ca/journal?c=science-and-the-environment) March...

**Coastal Erosion in Atlantic Canada** https://thestarfish.ca/journal/2024/03/coastal-erosion-in-atlantic-canada by [[Sierra Christodoulou]](https://thestarfish.ca/members/sierra-christodoulou) in [[Science and The Environment]](https://thestarfish.ca/journal?c=science-and-the-environment) March 20, 2024 **What is coastal erosion?** [[Coastal erosion]](https://climatlantic.ca/impacts/erosion/#:~:text=Coastal%20erosion%20is%20a%20natural,%2C%20rain%2C%20and%20surface%20runoff) is a process in which rocks and sediments at the coastline get broken down by waves, tides, winds, and storms and get carried off and deposited elsewhere along the coast. As a natural geological process occurring over millions of years, this deposition and displacement of land has [[forged Earth's beautiful cliffs and beaches]](https://www.britannica.com/science/coastal-landform/Landforms-of-erosional-coasts) to which we devote many holidays. However, the severity of coastal erosion over the past decade has put pressure on coastal landscapes and has placed more communities and ecosystems at risk.  **What's causing this risk? ** Global sea levels have risen at a rate of about 1.7 mm per year over the last century, but recent satellite observations are suggesting that [[3 mm per year could be a more accurate prediction]](https://link-springer-com.proxy3.library.mcgill.ca/content/pdf/10.1007/s11069-009-9380-5.pdf) of sea level rise in the past decade. Climate change is amplifying glacial meltwater and the rising atmospheric temperatures are increasing the thermal expansion of the water, which together increase sea levels and act comparably to a large storm surge. This leads to flooding and higher rates of coastal erosion, further endangering coastlines and putting coastal communities at risk.  **Why is this important to Canada's Atlantic coastlines?** Canada has [[226,000 kilometers of coastline, and up to 600,000 people are currently exposed]](https://ncceh.ca/resources/evidence-reviews/overview-canadian-communities-exposed-sea-level-rise) to rising seas and flooding. Therefore, the erosion of coastlines and riverbanks is causing large impacts on infrastructure, economy, livelihoods, and ecosystems. [[Over 1000 residences and 17 lighthouses]](https://link.springer.com/chapter/10.1007/978-3-319-53742-9_14) on and around Prince Edward Island are vulnerable to coastal erosion as rising sea levels and reductions in buffer zones bring communities closer to the water. [[Buffer zones act as a protection]](https://www.mdpi.com/2073-4441/13/20/2925) between the strong natural forces of the water, and the land where communities live, and as coastal erosion shortens the lateral distance of shorelines, the buffer zones shorten simultaneously. As a result, many communities may have to retreat inland, abandoning their homes and livelihoods.  Furthermore, the increase in the frequency and intensity of hurricanes can exacerbate the risks caused by coastal erosion and climate change. Since 1975, there has been a [[75% increase in category 4 and 5 hurricanes]](https://link-springer-com.proxy3.library.mcgill.ca/content/pdf/10.1007/s11069-009-9380-5.pdf) in the North Atlantic, which can generate more coastal flooding and erosion. [[Hurricane Fiona]](https://www.nhc.noaa.gov/data/tcr/AL072022_Fiona.pdf) in September 2022, which caused 3 billion USD in damages and left 500,000 customers without power in Atlantic Canada, led to [[10 meters of coastal erosion]](https://www.cbc.ca/news/canada/prince-edward-island/pei-fiona-national-park-dune-damage-1.6597053) in some areas of Prince Edward Island where the dunes were still recovering from Hurricane Dorian in 2019. Furthermore, much of the vegetation has been eroded which means with continued collisions from destructive hurricane waves, these fragile dunes will likely continue to collapse and be washed away. **Can coastal protection infrastructure help?** Hard infrastructure, such as dikes and barriers, can help protect coastlines, ecosystems, and communities from coastal erosion, but this isn't a save-all answer. Coastal erosion in some areas in Quebec is expected to be over 2 metres annually, and as a result, dikes were placed in areas such as [[Kamouraska Bay in the St. Lawrence River]](https://www.preventionweb.net/news/st-lawrence-shoreline-erosion-we-must-work-not-against-nature). While the purpose was to recover land for agricultural use, it trapped saltwater on farmland during flooding events in which the dikes were breached, impacting farmer livelihoods, and led to the loss of 3/4th of the marsh ecosystem. [[Wetland vegetation root systems]](https://www.cell.com/current-biology/pdf/S0960-9822(19)30550-0.pdf), such as grasses, bushes and trees, protect coasts against lateral (sideways) erosion and are crucial to the health and longevity of coastal ecosystems. Vegetation root systems stabilise the soil, so therefore the loss in marsh ecosystems in Kamouraska Bay not only reduces the marsh's biodiversity but also increases the rate of erosion on St. Lawrence River's wave-stressed shorelines, leading to a snowball effect and further destroying ecosystems.  However, part of the issue is not the infrastructure itself, but the lack of adaptive infrastructure that takes climate change and underlying problems into consideration. Adaptive infrastructure are nature-based solutions for safeguarding coastlines through incorporating or mimicking the area's natural ecosystem. [[97% of Quebec's coastal infrastructure is hard]](https://www.preventionweb.net/news/st-lawrence-shoreline-erosion-we-must-work-not-against-nature) infrastructure that, when used for local problems such as Kamouraska Bay's local flooding, can instead shift or exacerbate the problem. However, the development of nature-based solutions such as the [[Belcher Street Dike in Nova Scotia]](https://www.cbwes.com/work/project-belcher) have allowed the area to regenerate. The dike was relocated so that floodwater would be diverted away from the community and redirected to the river that previously held the overflow water, allowing water to return to the floodplain and restore the local wetlands.  **So what's the future of coastal erosion?** Climate change and hurricanes have made coastal erosion become a growing concern for communities, economies, livelihoods, and ecosystems globally and in Canada. Whilst coastal erosion existed millions of years ago, and will exist millions of years later, its effects can be mitigated if full consideration of the underlying problem and all assets that are involved and affected are considered.  If coastal erosion occurs in your area, there are a [[couple things you can do]](https://www.fairfaxcounty.gov/soil-water-conservation/drainage-problem-protect-eroding-land#:~:text=For%20areas%20with%20light%20erosion,are%20check%20dams%20or%20terraces.). Planting local vegetation can stabilise soil, but the vegetation must be able to adapt to the local climate, moisture and shade levels. In paths with exposed soil and heavy foot traffic, putting stepping stones, gravel or mulch can prevent erosion. Runoff can be redirected or captured with rain barrels, rain gardens, terraces, drains, and more. As a global and widespread process, coastal erosion cannot be approached locally, but rather holistically.