The Greenland Sea ecoregion follows the Greenland Exclusive Economic Zone (EEZ) definition and comprises the continental shelf waters and offshore areas. The Denmark Strait between Iceland and Greenland separates the ecoregion into a northern and southern subregion that differ with respect to ice coverage, influence of polar and Atlantic waters, and anthropogenic activity. The ecoregion borders five other ecoregions (Oceanic Northeast Atlantic, Icelandic Waters, Norwegian Sea, Barents Sea, and Arctic Ocean) and also the West Greenland waters (Figure 1).
The northern subregion is greatly influenced by cold and fresher polar waters from the East Greenland Current (EGC), which originates from the Arctic Ocean and covers a large part of the surface waters of the shelf (Figure 2). In the southern subregion the polar waters are constrained to a narrow coastal region on the shelf, which means that warmer and more saline Atlantic waters, originating from the Subtropical Gyre and transported by the Irminger Current (IC), are more prevalent in this subregion (Figure 2).
The ecoregion is dominated by an inflow of multi-year ice from the Central Arctic Ocean, with maximum coverage in March and minimum in September. The northern subregion has year-round sea ice, with nearly total to partial coverage in winter except for polynyas. In the southern subregion drift ice is seasonal (early spring), transported from the northern subregion in the East Greenland Current.
Much of the waters in the ecoregion are stratified shelf waters, with cold and fresher polar waters overlaying warmer and more saline Atlantic waters.
Figure 2 General pattern of surface ocean circulation in the ecoregion (0–1000 m). Blue arrows represent cold currents from the polar region and red arrows warm currents from the Subtropical Gyre (Gonzalez-Pola et al., 2019).
Regulation of human activities
As the ecoregion is within the Greenland EEZ, the management of marine resources are under Greenlandic authority. Fisheries targeting widely-distributed fish stocks (e.g. herring (Clupea harengus), mackerel (Scomber scombrus), and capelin (Mallotus villosus)) are managed by NEAFC or coastal state agreements. The International Whaling Commission (IWC) has regulations for the conservation and harvesting of whales. Other mammals are covered by the North Atlantic Marine Mammal Commission (NAMMCO). International shipping is managed under the International Maritime Organization (IMO). The Greenland Government and the commissions that manage fish stocks and the environment obtain advice from ICES and OSPAR.
Figure 1: The Greenland Sea ecoregion. The northern ICES ecoregions are outlined in black: AO (Arctic Ocean), GS (Greenland Sea), BS (Barents Sea), NS (Norwegian Sea), IW (Icelandic Waters), ONEA (Oceanic Northeast Atlantic), and West Greenland waters.