Wang, Z., Greenan, B.J.W., Hannah, C.G., and Layton, C. 2025. Past and future sea surface temperature

changes in the oceans surrounding Canada. Can. Tech. Rep. Hydrogr. Ocean. Sci. 404: v + 44 p

This study presents changes in the sea surface temperature (SST) in the oceans surrounding Canada using

past observations and model projections of future scenarios. The past changes are derived using an SST

product, HadISST, in which a recent period (2012-2022) was referenced to a 26-year climatology (1955-

1980). The future changes in SST are estimated using a 22-member ensemble of CMIP6 models. The SST

changes for overlapping periods from the CMIP6 ensemble and the HadISST in the 10 regions of the Canadian

shelf waters are in general agreement, although the CMIP6 results tend to overestimate the observed

changes by about 0.1 oC. One exception to this is the Scotian Shelf where the CMIP6 models underestimate

the observed SST change. The Gulf of Maine, Scotian Shelf, Gulf of St. Lawrence and southern Newfoundland

shelf are the regions with the largest observed SST increases around Canada. The Gulf of St. Lawrence has

the highest correlation (r=0.65) with the Atlantic Multi-decadal Oscillation (AMO) among the subregions in

the North Atlantic Ocean, and the British Columbia Shelf is correlated with the Pacific Decadal Oscillation

(r=0.58). Under the four climate scenarios (SSP1-2.6 to SSP5-8.5), among the mid-century (2040-2059)

annual mean SST changes (reference period of 1990-2014) in the 10 regions, the Gulf of St. Lawrence is

projected to have the largest increases in temperature (1.8 – 2.5oC), and Baffin Bay has the smallest increases

(0.5 – 0.9oC), However, for the summer means, the southern Beaufort Sea has the largest SST increase (2.4 -

3.1oC) with Baffin Bay having the smallest changes (1.3-2.1oC).

Cite this data as: Wang, Z., Greenan, B.J.W., Hannah, C.G., and Layton, C. (2025) Data of:

Past and Future Sea Surface Temperature Changes in the Oceans Surrounding Canada.

Published: October 2025. Ocean Ecosystems Science Division, Fisheries and Oceans Canada, Dartmouth, N.S.

https://open.canada.ca/data/en/dataset/3c336e55-4266-406a-922d-bbf8e717558c