Sea level rise

Since 1900, the average sea level has risen by about 20 centimetres. This increase has been accelerating since the 1990s.  

In 2023, the average sea level reached a new record, rising 10 cm higher than in 1993. That means the rate of rise more than doubled, from 1.4 mm/year for most of the 20th century to 3.6 mm/year between 2006 and 2016. 

Figure 1: Change in absolute sea level between 1993 and 2023 in millimetres (from NOAA, 2023). 

While the average sea level is rising all over the planet, the geological movements of the continents can accentuate or compensate for the sea level on a local scale due to the glacial context of certain regions, such as Quebec.

For example, in the Magdalen Islands, the relative sea level rose approximately 4 mm/year between 1964 and 2011. However, the increase was less marked in the Bas-Saint-Laurent and Côte-Nord regions, and it could be described as stable in the areas surrounding Québec City. In Nunavik, the relative sea level remained stable or even fell slightly. 

Figure 2: Relative sea level in Atlantic Canada (from Fisheries and Oceans Canada, 2022).