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1. Global environmental change and international law: the introductory framework

I. Trends in global environmental change
II. The development of international environmental law
III. Themes
IV. Important future themes
V. Organization of the book

Edith Brown Weiss

International law has been based on the relationship between independent states that exercise exclusive national sovereignty over their territories. Global change is altering this vision by causing states to realize that they are locked together in sharing the use of a common global environment. While human activities have always contributed to environmental change, it is only within the last half of this century that their effects have become global and serious, and in many cases irreversible. This has led to a growing awareness that the interests of humankind must constrain the interests of individual states. Moreover, actors other than states have become essential to managing global environmental change. These developments are leading to a fundamental shift in the paradigm of international law that is evolving in the international environmental field. This book examines some of the ways in which international environmental law is responding to global environmental change and suggests new directions for the field.

I. Trends in global environmental change

Concern among primarily industrialized countries about the serious risk of environmental harm to countries around the world motivated states to convene the 1972 Conference on the Human Environment, the first world conference on the environment.

The author thanks Steven Porter for his assistance, particularly with the chapter summaries.

By 1970 the world population had more than doubled since the beginning of the century (from 1.6 to 3.4 billion), industrial processes were generating unprecedented amounts of pollutants, and in some countries popular concern for the environment had sky-rocketed.)1 The United States, for example, had passed its first piece of national environmental legislation, the National Environmental Policy Act of 1969.

At the time of the Stockholm Conference countries were deeply divided over the issue of whether environmental protection and economic development were compatible. The conceptual breakthrough that provided the paradigm for joining these two important goals emerged from a meeting of experts held in Founex, Switzerland, just prior to the Stockholm Conference. Today countries recognize that sound economic development must be environmentally sustainable and are concerned about how to do this. They realize that we need to substantially increase the living standards of the poor in a manner that is environmentally sustainable. The issue in 1992 that divides countries is an equity one: how to finance environmentally sustainable economic development for present and future generations.

Today, 20 years after the Stockholm Conference, countries are concerned with global environmental problems that were either not yet identified or barely addressed. These include acid precipitation, ozone depletion, climate change, hazardous waste disposal, loss of biological diversity, and forest degradation and loss and land-based sources of marine pollution.

The trends in population, resource consumption, and environmental degradation that caused such concern in the early 1970s have continued, or accelerated, while our capacity to address them has increased at a slower rate, albeit arguably more rapidly than for some other problems.

Population growth, resource consumption, and technological development continue to be primary catalysts for global environmental change. By 1990, world population had reached 5.3 billion, more than triple that in 1900 and almost 2 billion more than in 1970. Current estimates are that world population will reach at least 8.5 billion by the year 2025.2 The bulk of population growth is projected to be in the developing world.3

The link between population growth and environmental degradation is complex and not well understood, as reflected in the several competing schools of thought on the issues. However, a larger population generally translates into greater demands on the Earth's resources. As has been demonstrated, population size that exceeds local carrying capacity of the ecosystems can cause soil depletion, deforestation, and desertification. If we multiply projected population increases by the substantially higher standard of living that equity requires for impoverished communities today and for future populations, the potential demands on the environment in the decades ahead are dramatic.

Since 1968, the world's consumption of energy has grown. Overall, the total energy requirements of industrialized countries have increased almost 30 per cent from 1970 to 1988, although this masks two periods of decline after the oil-price shocks.4 The rate of increase in energy consumption in the developing countries has declined, but remains high. Most of the world's energy continues to come from burning fossil fuels, whose general by-products are a primary contributor to global warming. Annual emissions of carbon dioxide from fossil fuels more than doubled from 1960 to 1988.5

In addition, the release of ozone-depleting chloro-fluorocarbons (e.g. CFC-11 and CFC-12), which were virtually non-existent prior to World War II, has risen from 35 million kilograms in 1950, to 506 million kilograms in 1970, and to 707 million kilograms by 1988.6 Fortunately, countries have now agreed to phase out their production and consumption by the year 2000, and likely sooner. Human-caused emissions of trace metals have followed a similar growth pattern.

Agriculture demands and practices have also raised important environmental concerns. Irrigated crop land, which accounts for about 17 per cent of the world's crop land and one-third of the global harvest,7 is being eroded by waterlogging and made less productive by salinization (the cumulative build-up of salts left by evaporation of irrigation water). Deforestation, loss of biological diversity, and soil erosion have significantly increased.8

Fresh water continues to be a critical resource. In addition to the well-documented water-quality problems of surface waters, new concern has emerged over groundwater resources. Contamination results from the disposal of wastes, both hazardous and non-hazardous, and from the seepage of chemicals such as pesticides and fertilizers into the aquifers. Pesticides, whose use has doubled in the US since 1961, have created groundwater contamination problems in 40 of the 50 US states.9 Pesticides are used worldwide, with an over-$18-billion market in 1987, and their use is frequently unregulated or not well monitored. The agricultural use of chemicals has also grown dramatically, leading to increased run-off and contamination of lakes, streams, and groundwater.10 While the open oceans remain relatively undisturbed by humankind's activities, the oceans' coastal zones, the most biologically productive areas, are under severe pressure from population growth and development activities. In addition, there is evidence that we may be reaching the limits of the seas' natural productive capacity. The average annual catch of marine fisheries (79 million metric tons for 1987) are at or near estimates of their sustainable yield (between 62 and 96 million metric tons per year).11

In the past, pollution and environmental degradation have operated largely on the local level and hence their effects have been isolated in impact. Given the increasingly global scale of environmental degradation and the ever-increasing volume of pollutants entering the environment, however, their effects are now being felt on regional and global levels. In addition, the scope and irreversible nature of some global changes reach through time to affect the well-being of future generations.

II. The development of international environmental law

Modern international environmental law dates to approximately 1972, when countries gathered for the United Nations Stockholm Conference on the Human Environment and the United Nations Environment Programme was established. Many important legal developments took place in the period surrounding the Conference, including negotiation of the World Heritage Convention, the Convention on International Trade in Endangered Species, the London Ocean Dumping Convention, and, shortly after the Conference, the UNEP regional seas conventions. Since then, there has been a rapid rise in international legal instruments concerned with the environment, to the point where we are concerned today with developing new means for coordinating the negotiation and implementation of related agreements, in particular their administrative, monitoring, and financial provisions.

At the turn of the century there were relatively few multilateral or bilateral international environmental agreements. International environmental law was based on the principles of unfettered national sovereignty over natural resources and absolute freedom of the seas beyond the three-mile territorial limit. Such international agreements as existed largely addressed issues concerning boundary waters, navigation, and fishing rights along shared waterways, particularly the Rhine River and other European waters. It is worth noting, however, that Article IV of the 1909 United States-United Kingdom Boundary Waters Treaty stated that water "shall not be polluted on either side to the injury of health or property on the other."12

Early in the century, a few agreements were concluded to protect commercially valuable species, such as the 1902 Convention for the Protection of Birds Useful to Agriculture and the Treaty for the Preservation and Protection of Fur Seals signed in 1911.13

The classic adjudication during the first part of the century was the Trail Smelter Arbitration between Canada and the United States, which affirmed Canada's responsibility for the damage from copper smelter fumes that transgressed the border into the state of Washington.14 The language of the Arbitral Tribunal has been widely cited as confirming the principle that a state is responsible for environmental damage to foreign countries that is caused by activities within its borders.15 The fact that the Arbitration is a rare example of international environmental adjudication in this early period has given it an unusually important place in the legal literature.

By the 1930s and 1940s, conservation and preservation had emerged as conceptual approaches to natural-resource management, which led to agreements to protect fauna and flora. These agreements included the 1933 London Convention on Preservation of Fauna and Flora in Their Natural State (focused primarily on Africa) and the 1940 Washington Convention on Nature Protection and Wild Life Preservation (focused on the Western Hemisphere). Conventions relating to whaling practices, other ocean fisheries, and birds were also negotiated during this time.

During the 1950s and early 1960s, new environmental concerns emerged. Agreements governing international liability for nuclear damage were negotiated, as was the 1954 International Convention for the Prevention of Pollution of the Sea by Oil.

In the late 1960s, there was a significant increase in the number of multilateral international environmental agreements. Several conventions were negotiated relating to interventions in case of oil-pollution casualties, to civil liability for oil-pollution damage, and to controlling oil pollution in the North Sea. The African Convention on the Conservation of Nature and Natural Resources was concluded in 1968.

Since 1970, hundreds of international environmental instruments have been concluded. If we include bilateral and multilateral instruments (binding and non-binding), there are more than 870 international legal instruments that have one or more provisions addressing environment. The relevant players on the international environmental law stage now include not only states but corporations, intergovernmental and non-governmental organizations, and individuals.

The subject-matter of international environmental agreements has expanded significantly from the focus in the first half of this century on facilitating navigation, guaranteeing fishing rights, and protecting particularly valued animal species; today there are agreements to control pollution in all media, conserve habitats, and protect global commons, such as the high-level ozone layer.

Ever since 1972, the scope of international agreements has expanded significantly: from transboundary pollution agreements to global pollution agreements; from preservation of designated species to conservation of ecosystems; from control of direct emissions into lakes to comprehensive river-basin-system regimes; from agreements that take effect only at national borders to ones that constrain activities and resource use within national borders, such as those for world heritages and wetlands. The duties have also become more comprehensive: from a focus on research and monitoring to provisions for reductions in pollutants. Most notably, there is not a single example in which the provisions of earlier conventions have been weakened; in all cases, they have been strengthened or their scope has been expanded.

There is a growing realization in the international community that the time has come not only to monitor and research environmental risks but also to reduce them. Thus we have moved from international agreements that deal largely with research, information exchange, and monitoring to agreements that require reductions in pollutant emissions and changes in control technology. The Protocol on Sulphur Dioxide to the UN ECE-Convention on Long-Range Transboundary Air Pollution calls for a 30 per cent reduction in national annual sulphur emissions or their transboundary fluxes by 1993,16 and the Montreal Protocol on Substances That Deplete the Ozone Layer, including the 1990 Adjustments and Amendments, requires that chloro-fluorocarbons and haloes be phased out (except for a few essential uses) by the year 2000.17 This focus on pollution prevention is likely to continue as we come to appreciate the limited capacity of our environment to absorb the by-products of our society.

The increase in international agreements concluded in just the last six years, from 1985 to 1992, illustrates the increasingly rapid rate at which international environmental law is being formed. During this period, countries have negotiated a surprisingly large number of global agreements. These include the Vienna Convention on the Protection of the Ozone Layer, which provides a framework for protecting the ozone layer but primarily calls for research, monitoring, and exchange of information; the Montreal Protocol on Substances That Deplete the Ozone Layer with the London Adjustments and Amendments; the Protocol on Environmental Protection (with annexes) to the Antarctic Treaty; the Basel Convention on the Transboundary Movements of Hazardous Wastes and Their Disposal; the London Guidelines for the Exchange of Information on Chemicals in International Trade; the two International Atomic Energy Agency conventions on Early Notification of a Nuclear Accident and on Assistance in the Case of a Nuclear Accident or Radiological Emergency; and the International Convention on Oil Pollution Preparedness, Response and Co-operation.

Negotiations for regional environmental agreements have proceeded at a similarly rapid rate. Under the auspices of the United Nations Economic Commission for Europe (ECE), countries have concluded three protocols to the UN ECE Convention on Long-Range Transboundary Air Pollution: a protocol providing for 30 per cent reductions in transborder fluxes of sulphur dioxides, a protocol freezing the emissions of nitrogen oxides, and a protocol controlling emissions of volatile organic chemicals. They have also concluded agreements on environmental-impact assessment and transboundary industrial accidents and transboundary watercourses and international lakes.

In the regional seas programme, countries have concluded the South Pacific Resource and Environmental Protection Agreement with two protocols, one on dumping and the other on emergency assistance. Under the Caribbean Regional Seas Convention, countries have negotiated a new protocol on protected areas, and are considering negotiation of a protocol on land-based sources of marine pollution.

For freshwater resources, countries have concluded an innovative, comprehensive agreement for the Zambezi River Basin. Canada and the United States agreed to a protocol to their 1978 Great Lakes Water Quality Agreement that addresses groundwater contamination affecting the Great Lakes and the airborne transport of toxics into the Great Lakes. Amazon Basin countries have issued the Declaration of Brasilia and provided under the auspices of the Amazon Pact for the establishment of two new commissions, one to conserve the fauna and flora and the other to protect indigenous peoples. In Asia, members of ASEAN have concluded the Convention on the Conservation of Nature, which provides ecosystem protection and controls on trade in endangered species.18

Within the European Community, there have been many important developments, including notably the Single European Act, which provides clear authority for the Community to act on environmental and natural-resources issues. The Community has already issued many directives and regulations designed to control pollution and protect the environment. A new European Environment Agency and European Environment Information and Observation Network are being established.

Bilateral agreements have also proliferated during this period. There are important examples within North America. The United States has signed bilateral agreements on the transport of hazardous wastes with Canada and Mexico. A recent air-pollution agreement between the United States and Mexico addresses urban air pollution problems in Mexico City. In Latin America, Brazil and Argentina concluded an agreement (contemporaneous with the two IAEA agreements) that provides for consultation in case of nuclear accidents in either country.

Many of these agreements were thought to be impossible 10 years ago; some were thought impossible as briefly as 2 years before they were concluded. The provisions in the new agreements are generally more stringent than in the previous ones; the range of subject matter is broader; and the provisions for implementation and review are more sophisticated. One encouraging observation from this experience is that the learning curve demonstrated in international environmental law is unexpectedly steep. This should give us hope that the international community may be able, with at least some success, to confront the immense challenges posed by global environmental change.

Given the astonishing developments of the past 20 years, what then awaits us in the future?

In the next decade more international agreements and other legal instruments will be concluded. The rate of negotiating these instruments shows no sign of abating. Countries have just reached agreement on a framework convention on climate change, forest principles, and an agreement on biological diversity. As this book goes to press, negotiations continue on several agreements: an agreement on the marine transport of hazardous and noxious substances, and a liability protocol to the Basel Convention on Transboundary Movements of Hazardous Wastes.

At the same time, however, a countervailing theme is emerging-one that says it is time to slow the rate of negotiating international agreements. Some countries, especially the developing ones, are becoming overtaxed by the resources needed to engage in negotiations and to implement effectively the agreements already concluded. This may mean that a "go slow" light will appear and caution against continuing the rapid pace of concluding new international agreements. In turn this may presage greater reliance on international legal instruments that are not formal conventions, or what some jurists call "soft law."

The new international conventions are likely to continue to be ever more demanding in terms of the actions they ask of countries. Frequently this may take the form of a framework convention, followed by protocols that provide for detailed obligations. This is the form of the recent Antarctic Environment Protocol (with four annexes), the Vienna Ozone Layer Convention (with the Montreal Protocol), and the regional-seas conventions.

Further, there is likely to be increased emphasis on monitoring compliance with the conventions and on providing means to facilitate implementation and compliance. The role of non-governmental organizations in the negotiation and implementation of agreements has grown and will likely continue to grow.

Finally, we will likely see new attention to the trade implications of the agreements that are negotiated and to addressing issues of consistency between environmental and trade regimes.

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