Sea Level Rise

Why is sea level rising?

Seas around the globe are rising because of human-caused climate change. Climate change is leading to a warmer Earth resulting in thermal expansion of water molecules in the oceans and melting ice caps and glaciers. In the Maritimes sea level is increased by subsidence, or the sinking of coastal lands. Lands are sinking here because a huge heavy glacier used to cover Canada but since it began retreating, the edges of the continent have begun to sink (just like when you jump on a bed and the edges of the mattress move up and down!). Subsidence contributes 5-10% to the projected relative sea-level change by 2100 and makes our region more vulnerable to sea level rise.

The dykes have already been overtopped by 1-2cm in places during storm surge events

How fast will sea level rise and by how much?

Due to emissions forcasts and subsidence, the latest scientific research predicts sea levels around New Brunswick may rise by  1 metre or more by 2100. There is time to prepare, adapt, retreat where needed, and use nature-based approaches (see below).

What could happen?

  • Salt water intrusion into wells
  • Increased coastal erosion
  • Low-lying coastal communities could flood before the end of the century
  • Permanent submergence of areas of coastline
  • Transportation routes cut off
  • Trade and commerce impacted due to the rail line and Trans Canada Highway that run through the low lying Chignecto Isthmus region
  • Storm surges will be higher and more devastating

Storm surge from hurricane Patricia forces water levels near top of dykes and train tracks

What can we do about it?

There are things we can all do to prepare, adapt and take action against rising sea levels:

  • Explore sea level rise maps for your region and get to know the risks
  • Attend sea level rise and flood risk reduction workshops to learn more
  • Flood proof your home if necessary
  • Have an emergency kit and be prepared to evacuate in the event of a storm surge
  • Think before you build or buy
  • Build back from the coast and build higher if you have the chance
  • Keep trees and shrubs in place to help anchor your shoreline
  • Plant hardy vegetation to manage erosion (see a plant list below)
  • Don’t mow up to the shoreline or riverbanks
  • Plant a natural buffer between you and the water
  • Join an environmental group in your area to help take action and address climate change and sea level rise

Make sure you and your family have an emergency kit and family flood plan

How can we slow down sea level rise?

We need to work together to reduce greenhouse gas emissions globally:

  • Save energy at home and work (turn things off when not in use, insulate walls, basements and attics, etc.)
  • Use energy more efficiently (perform energy retrofits, purchase Energy Star appliances, switch to more efficient heating like heat pumps, etc.)
  • Support renewable energy – invest in community projects, go solar at home and at work. (Did you know the sun delivers more energy to Earth in one hour than humanity consumes over the course of a year!)
  • Find ways to leave fossil fuels in the ground
  • Green your ride – travel less, take the bus, carpool, bike, go electric
  • Get involved and support organizations making e a difference
  • Vote for political representatives who share your values and will implement the changes you want to see

How can nature help?

Nature can help us adapt to rising sea levels:

  • Natural shorelines (e.g. trees, shrubs, grasses, etc.) help stabilize & protect shorelines from erosion.
  • Salt marshes help reduce wave energy and can rise as the sea rises.
  • Dunes systems help absorb wave action and storm surges.

Salt marshes are a natural buffer to sea level rise, helping absorb wave action

What to plant for a natural coastal shoreline?

Naturally stabilize your shoreline by planting a variety of native, salt tolerant plants:

  • American Mountain Ash
  • White Spruce
  • Trembling Aspen
  • Tamarack/Hackmatack/Eastern Larch
  • Black Elderberry
  • Wild Rose
  • Bay Berry
  • Spotted Joe Pye Weed
  • Spartina Grass/Cord Grass (for salt marsh areas)
  • Marram Grass (for dunes areas)
  • American Beach Grass
  • Spiraea/Meadow Sweet/Steeple Bush

Did you know?

  • 60% of New Brunswickers live within 50kms of the coast
  • New Brunswick has 5,500kms of coast line

 

Sea Level Rise Signs

Look for educational sea level rise signs across the Chignecto Isthmus in spring 2021 in Cape Jourimain, Port Elgin, Baie Verte and Johnson’s Mills. They show a historic coastal flood level and what the same storm could look like in 2100 with sea level rise. Here is an example of one of the signs:

**Please note: We are so sorry to report that the Baie Verte sign has gone missing! So you only need to find the other three to be entered in the contest now. 

 

Memramcook-Tantramar Area Flood Risk Maps:

Sackville current 1:100 flood risk map (2013)

Port Elgin current 1:10 flood risk map (2013)

Memramcook flood risk map (2013) The map shows current (blue) and future (purple) 100 year flood events in Memramcook. Flood depths equal 7.58 m and 8.6 m respectively.

12m storm surge across the Tantramar Marshes (2013)

Source for above maps: EOS Eco-Energy Climate Change Toolkit

Sackville Hydrographic Map  (Source: Southeast Regional Service Commission)

Note: 1:100 year storm is a storm that has a 1% chance of happening any time.

You can find out more at:

Sea level rise will make today’s storm surges that much higher in the future. A 12 m storm surge could make Nova scotia an island. The white line shows a possible route along the highest points of land. Webster et al., revised December 2012

The location of dykes and their heights. Lieske and Bornemann, 2012

The 2010 nor’easter in Port Elgin caused flooding and pushed cottages and homes off their foundations. Sea level rise will make storm surges higher in the future. Photo credit: T. Murphy

Shediac Bay Watershed Association, EOS, and students from Port Elgin Regional School plant a natural buffer along the lower Gaspereau River in fall 2019.