Environmental Thematic Maps and Graphics:
Winter sea surface temperature departures (2005 to 2017) from the climate normal, by depth class, marine ecoregion

The title of this map is “Winter sea surface temperature departures (2005 to 2017) from the climate normal, by depth class, marine ecoregion.” This map provides a visual representation of the average winter surface temperature change of Canada’s oceans in the winter season.

On the page, there are three maps and two legends to the upper left and right. The first map (top) displays all of Canada, the second map (left) displays the West Coast and the third map (right) displays the East Coast. On the maps there are small numbers corresponding to marine ecoregions.

The maps show the change in sea surface temperature in degrees Celsius (°C) by marine ecoregion in different shades of blue, yellow, orange and red. The first legend (left) lists the map labels and corresponding marine ecoregions. The second legend (right) contains nine temperature categories in degrees Celsius (°C): <-0.5 (navy blue), -0.5 to -0.25 (dark blue), -0.25 to -0.1 (light blue), -0.1 to 0 (aqua), 0 to 0.1 (pale yellow), 0.1 to 0.25 (yellow), 0.25 to 0.5 (pale orange), 0.5 to 1 (orange), ≥1 (red). The legend contains three boundary categories: fine dashed lines indicate provincial boundaries, fine black lines indicate marine ecoregion boundaries and fine grey lines indicate marine depth classes.

The maps show that compared to the 1981 to 2010 climate normal, the 2005 to 2017 average winter sea surface temperature generally increased on the East Coast apart from the Gulf of St. Lawrence where it decreased. The Strait of Strait of Georgia and Southern Shelf also had decreased average temperatures, while the Offshore Pacific sea surface temperature increased slightly. The Northern Shelf and Arctic marine ecoregions had areas of both increase and decrease. The Scotian Shelf experienced the greatest increase in temperature and the Strait of Georgia experienced the greatest decrease in temperature.

Notes: The climate normal is the three-decade average of climatological variables from 1981 to 2010. Winter data are from January to March

Sources:
Locarnini, R. A., et al., 2018. World Ocean Atlas 2018: Volume 1: Temperature, A. Mishonov (Technical Ed.), NOAA Atlas NESDIS 81, 52 pp., https://www.nodc.noaa.gov/OC5/SELECT/woaselect/woaselect.html (accessed November 15, 2019).