Since the early 1920s, the annual mean sea surface temperature of the Faroe Shelf Water has increased 0.7°C (see figure 5).
The previously documented pattern on the covariation of salinity and temperature of the Atlantic water has changed since the mid‑2010s, when freshening of the Subpolar Gyre was not accompanied by a similar temperature change. It remains to be shown if the decoupling is a result of climate change.
Nutrient concentrations of the Subpolar Gyre waters, essentially silicates, have shown a declining trend in recent decades. The cause or origin of the observed trend in nutrients is not known, but it is predicted that future climate derived changes will result in increasing stratification of the oceans with a further reduction in nutrients because of decreasing overturning of deep nutrient rich waters.
Increased temperatures may affect the fat content of sandeel negatively and therefore also impact species that feed on them. There is not yet evidence of the impacts of rising temperature on cod spawning on the Faroe Plateau or cod biomass on the Faroe Bank. Also, there is clear evidence in the ecoregion to support the pattern observed in other ecoregions on the movement of fish and marine mammals poleward because of increasing temperatures. Knowledge on the impacts (both direct and indirect via trophic interactions) of temperature and nutrients on the biota in the ecoregion is currently limited.
Figure 5: Annual average
temperature observed at Mykines (1914-1969) and Oyrargjógv (since 1991), both
representing sea surface temperature of the well‑mixed Faroe Shelf Water
(Larsen et al., 2008 and updated)