Freshwater: the Polar Regions

Arctic

The Arctic holds much of the world's freshwater supply and its landscape is dominated by freshwater systems. The two main permanent ice fields are the ice pack of the Arctic Ocean (8 million km²) and the Greenland ice cap (1.7 million km²), which together hold 10 per cent of the world's freshwater. The Greenland ice cap produces about 300 km³ of icebergs a year. The Arctic has several of the world's largest rivers. They pour 4 200 km³ of freshwater into the Arctic Ocean annually along with about 221 million tonnes of sediment (Crane and Galasso 1999, AMAP 1997).

Low temperatures, low nutrient, short light availability and a brief growing season limit the primary productivity of Arctic freshwater systems. This in turn restricts the animal life that can be supported. Nevertheless, the river systems are heavily populated by several fish species such as the Arctic charr, and the North Atlantic and Pink salmon. In recent years, the overall warming trend plus increased recreational and commercial fisheries use have put pressure on these populations. Accidental introduction of alien species and increased fish farming is another source of concern (Bernes 1996). Eutrophication is a recent problem in several lakes in Scandinavia where human settlements have raised nutrient levels.

Northbound rivers are major pathways of pollutants from sources far inland, especially in the Russian Federation. In the spring, these contaminants are deposited into the freshwater systems and eventually into the marine environment and can be transported thousands of kilometres from their sources via the Arctic's marine circulation patterns. Contaminants include chemicals from agricultural, industrial and petroleum production, radionuclides from nuclear testing and military activities, and water soluble salts (Crane and Galasso 1999). The Arctic countries adopted a circumpolar Regional Programme of Action for Protection of the Arctic Marine Environment against Land-based Activities (based on the Global Programme of Action for the Protection of the Marine Environment from Land-based Activities) as well as National Programmes of Action in some countries, including the Russian Federation. These instruments are too recent to assess long-term effectiveness (PAME 1998).

Opposition to damming is strong in the Nordic countries. During 1975-2001, the Cree people fought the government of Quebec over environmental damage to their lands. In a surprise move in October 2001, however, the Cree reversed their stand and signed an agreement in principle to allow the government of Quebec to build another large power development project on the Eastmain-Rupert river system in exchange for a cash settlement. In 2000, a hydroelectric power project that would have flooded an important wetland was rejected (Arctic Bulletin 2001). In 2001, Iceland's National Planning Agency rejected plans for a hydroelectric power project that would have dammed two of the three main rivers flowing from Europe's largest glacier and destroyed a vast wilderness.

Since the 1970s, surface air temperatures appear to have increased on average 1.5°C per decade over continental Siberia and western portions of North America, both of which are major sources of freshwater into the Arctic basin. The opposite trend is occurring in Greenland and Canada's eastern Arctic where there is a negative trend of -1°C per decade (AMAP 1997). The warming trend has resulted in thawing of the continuous permafrost in Alaska and northern Russia (Morison and others 2000, IPCC 2001).

Arctic countries have partially responded to threats to their freshwater systems by establishing protected areas and designating important wetland areas under the Convention on Wetlands of International Importance. Nearly half the protected area in the Arctic is the Greenland ice cap and glaciers which store freshwater.