Global Environment Outlook 3 (GEO 3)

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STATE OF THE ENVIRONMENT AND POLICY RETROSPECTIVE: 1972–2002

crashes of populations of commercially important species such as the cod and Atlantic salmon off the coasts of Canada and Greenland, and herring in the Norwegian and Icelandic waters. Despite strict conservation measures including no-catch zones, recovery has been slow and uncertain. Other species such as the haddock stocks between northern Norway and Svalbard have declined more steadily (Bernes 1993, 1996, CAFF 2001). Between the 16th and 20th centuries, massive overexploitation of several whale species occurred. Although some species have recovered to sustainable levels, others have not and are still subject to strict domestic or international regulations (for example, the bowhead whale through International Whaling Commission quotas). Illegal exploitation, including of endangered species, and overly generous quotas are a constant threat (CAFF 2001). Pollution Contaminants are another source of pressure on the Arctic marine environment. The annual spring influx of meltwater carries contaminants which accumulate in the estuaries and deltas and also enter the mixed layer where they are transported to the North American coast. Airborne contaminants from industrial and agricultural activities at lower latitudes are also deposited in the ocean where they can accumulate in sea ice. These contaminants are bioaccumulated in sea mammals and in turn are taken up by Arctic peoples (AMAP 1997, Crane and Galasso 1999).

Coastal and marine areas: the Polar Regions THE ARCTIC

The Arctic marine environment covers approximately 20 million km 2 and includes the Arctic Ocean and several adjacent water bodies. Nearly half of the ocean floor is continental shelf, the highest percentage among all oceans. Movements of Arctic waters play a significant role in the global ocean regime (AMAP 1997), and in regulating the global climate (see figure).

When warm, salty North Atlantic water reaches the cold Arctic, it becomes denser as it cools, and therefore sinks to deeper layers of the ocean. This process of forming deep water is slow but takes place over a huge area. Every winter, several million cubic kilometres of water sink to deeper layers, which move water slowly south along the bottom of the Atlantic Ocean

The global ocean circulation

shallow, warm

deep, cold

Source: AMAP 1997

The Arctic marine environment is rich in fish biodiversity and abundance. The commercial fisheries of the Barents and the Bering systems are among the most productive in the world (Kelleher, Bleakly and Wells 1995), with the Bering Sea accounting for 2–5 per cent of the world’s fisheries catches (CAFF 2001, Bernes 1996). Resident and migratory marine mammals include whales, seals and sea lions. The polar bear is also often classified as a marine mammal because it frequents sea ice in search of prey. Many of the indigenous communities of the Arctic have traditionally depended on these marine resources for their livelihood. Other natural resources include vast oil and gas reserves along the continental shelves as well as important mineral deposits. However, there are growing concerns about the negative impacts of development activities on the ecology of the Arctic especially in ice-prone areas and critical habitats. Resource degradation Overexploitation of fisheries is a major concern in the Arctic. Since the 1950s, there have been spectacular

Stocks of Arctic fisheries (thousands of adults)

200

150

100

50

0

1972

1974

1976

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

Southeast Alaska (eastern stock) Alaska (western stock)

Russia (western stock) British Columbia (eastern stock)

Oregon and California (eastern stock)

Stocks of commercially important species such as the cod, Atlantic salmon and herring have declined in many of the Arctic fisheries; despite strict conservation measures, recovery has been slow and uncertain

Source: CAFF 2001