North America Environment Profile

General Trends:

Trends in environmental quality in North America are mixed. On the positive side are improvements in some aspects of air and water quality, and reduced levels of soil erosion in much of the region. On the negative side are sharp declines in fish stocks in major marine fisheries, continued logging pressures on old-growth forests, growing invasions of exotic species and other threats to biodiversity, and increasing outbreaks of toxic organisms in estuaries and coastal zones associated with excess run-off of nutrients. Success in reducing emissions of some toxic industrial materials must be compared with continued high levels of industrial use of such materials and slow progress in cleaning up toxic waste sites. Success in phasing out production of CFCs and other ozone-depleting gases must be balanced against failure to reduce emissions of carbon dioxide, the primary greenhouse gas, and hence the region's growing contribution to the risk of climate change.

Beyond these specific issues, and underlying all of them, is the scale of economic activity in North America. The large and robust North American economy brings many benefits, stimulating job creation, and increasing welfare and opportunities for the region's inhabitants. But it also puts increasing stresses on regional environmental quality and has major impacts across the global environment. The United States and Canada have among the highest per capita consumption of energy and other natural resources in the world, and they contribute a disproportionate share of global emissions of greenhouse gases. North American consumption also provides strong incentives for increasing international trade, leading to increased industrialization and resource use throughout the world. Thus the footprint of North America's impact on the environment stretches well beyond the region itself.

Discussion of Mexico is included in the North American chapters on topics heavily affected by cross-border issues such as conservation of biodiversity and migratory species, transportation management, watershed management and air pollution. For other issues Mexico is included in the Latin America section of the report. Thus, unless explicitly indicated, North America here refers to Canada and the United States.

Key Facts

North Americans use more per capita energy and resources than any other region. This causes acute problems for the environment and human health. The region has succeeded, however, in reducing some environmental impacts.

The North American region is at critical environmental cross-roads: important decisions have now to be made that will determine whether the region's economic activity and patterns of production and consumption will become more sustainable.

There is continuing concern about the effects of exposure to pesticides and other toxic compounds on human health and the environment in general.

Emissions of CO, VOCs, particulates, SO2 and lead have been markedly reduced over the past 20 years.
Fuel use is high - in 1995 the average North American used more than 1 600 liters of fuel (compared to about 330 liters in Europe).

The oxygen-depleted 'dead zone' that now appears off the US Gulf Coast each summer - at the peak of fertilizer run-off from the Corn Belt - is the size of New Jersey.

Global warming could move the ideal range for many North American forest species some 300 km to the north, undermining the utility of forest reserves established to protect particular plant and animal species.

The impact of development on critical biological resources is an important issue across the region. Changes to ecosystems caused by the introduction of non-indigenous species are of particular concern.

Fish stocks off the east coast have nearly collapsed. The Atlantic finfish catch declined from 2.5 million tonnes in 1971 to less than 500 000 tonnes in 1994.

Forest

The past 100 years have brought both gains and losses to North America's regional forest cover, with substantial regrowth in the eastern United States and Canada. Overall, the extent of forest cover has stabilized in many parts of the region.

The quality of North America's forests, however, has deteriorated. While the world's second largest expanse of intact, natural forest is in the boreal regions of North America, forests in the United States are becoming increasingly fragmented and biologically impoverished, invaded by exotic species, or lacking in the characteristics that support viable populations of indigenous species

Fresh Water

North America has an abundant supply of freshwater resources but it is unequally distributed across the region. Surface and groundwater sources together provide an annual 5 308 km3 of renewable and fossil water to the two countries, which is about 13 per cent of the global total. On a per capita basis, Canada has 10 times more water resources than the United States. However, water scarcities occur in many parts of North America, including some parts of Canada's Prairie Provinces and the US southwest.

Marine and Coastal Areas

North America's coastline is at least 400 000 km long and is marked by a diversity of ecosystems, including estuaries, bays, inlets, barrier islands, fjords, tidal flats, lagoons, salt marshes, mangrove swamps, coral reefs, deltas and dunes. These areas support a profusion of marine resources, many of which are harvested commercially, as well as recreational and tourist activities. More than 50 per cent of the US population lives in coastal areas and by the year 2025 this will reach 75 per cent. Coastal areas are thus economically significant.

Yet the ocean's living resources and the benefits derived from them are threatened by fisheries operations, chemical pollution and eutrophication, alteration of physical habitat, and invasions of exotic species. New threats may be caused by ozone depletion and human-induced climate change.