Coastal

Photo: low tide © iStock.com/liquidfog
Low tide, New Brunswick

Atlantic coastal ecosystems

Increase in development along Atlantic coasts

Number of lot registrations (thousands), within 2 km of the Nova Scotia coastline
Graph: increase in development along Atlantic coasts. Click for graphic description (new window).
Source: adapted from CBCL Limited, 20093, data from N.S. Property Online Database

Coastal development, including converting natural ecosystems to built-up areas, often increases sensitivity to erosion, impairs
coastal water quality, and alters wildlife habitat. In Nova Scotia, although increased urbanization has led to population declines
in many rural areas, human population along the coast has increased.3 In the more densely populated areas of Newfoundland, where human activity has been modifying the shoreline for more than 100 years,22 many types of activities contribute to increasing rates of erosion.9 For example, compaction of beach sediment by all-terrain vehicles leads to incoming waves washing further landward, increasing erosion above the mean high-tide line.23

Decline in wetlands and beach and dune habitat, Atlantic coast

Percent change, 1944 to 2001
Graph and map displaying decline in wetlands and beach and dune habitat. Click for graphic description (new window).
Source: adapted from O'Carroll et al., 200617 and Hanson et al., 200618

Coastal wetlands and beach and dune habitats declined at five sites in southeastern New Brunswick between 1944 and 2001. Total losses at each site ranged from 7 to 18 ha for beaches and dunes, and from 30 to 55 ha for wetlands. Erosion, removal of sand for aggregate production, and increased hardening of the foreshore for development have contributed to these losses. Beaches and dunes provide important habitat for species such as the endangered Atlantic population of piping plovers, which decreased by 17% from 1991 to 2006, partly due to habitat loss and degradation from accelerating coastal development.19-21

Sea-level rise, storms, and coastal erosion

Increase in water level in Charlottetown Harbour
Metres above reference level on land, 1911 to 2008
Graph:  increase in water level in Charlottetown Harbour. Click for graphic description (new window).
Source: adapted from Marine Environmental Data Service, 2008 in CBCL Limited, 20093

Sea-level rise and associated storm impacts are likely to increase erosion along the Atlantic coast.3, 17, 24, 25 Water level relative to land in six Atlantic harbours is currently rising at rates from 22 to 32 cm per century, over half of which is due to land subsidence.3 (The land in this region is still affected by changing ice and water loads following glacier retreat.) The remainder of the increase, about 12 cm per century at Charlottetown, is a signal of global and regional sea-level rise. This rate is anticipated to increase due to climate change.4, 26 Canada's Atlantic coast is particularly sensitive to ecological damage from sea-level rise because there are many low-lying areas with salt marshes, barrier beaches, and lagoons.27 Impacts from sea-level rise are compounded by the effects of storm surges, which are increasing in number and intensity because of increases in tropical storms.9, 28-31