much better ecological health now than they were fifty or more years ago. Other examples include cooperative programs with Canada, Mexico, and Central American nations to conserve habitats for migratory species (waterfowl and neotropical birds) that spend part of their life cycle in the United States. For instance, the United States will spend about $140 million on the North American Waterfowl Management Plan in 1991 and 1992-with about half of this coming from the federal government. ESTABLISHING SPECIALLY PROTECTED AREAS The U.S. government has established specially protected areas or habitats on about 10 percent of the U.S. land mass (about 91 million hectares or 225 million acres) (USDA/DOI 1992). Of this area, 90 percent, or over 80 million hectares (200 million acres), is federally protected as national parks, wildlife refuges, wilderness areas, and wild and scenic rivers. Little or no development is allowed in these areas, which cover a wide variety of ecosystems. Since 1970, the area of national park and wildlife refuge systems has almost tripled to over 68 million hectares (169 million acres), while national wilderness areas have increased eightfold to 38 million hectares (95 million acres). The total length of the national wild and scenic river system has increased ninefold to 9,500 miles over the same period. Many of these additions are in Alaska. A substantial portion of the 28 million hectares (70 million acres) of state and local government land in the United States is classified as specially protected land (Daugherty 1991). All fifty states have state forest and park systems, natural heritage programs, and regulations protecting forests. Approximately forty states have established resource management systems whose explicit purpose is to protect “natural areas" or similarly designated areas. Additionally, several states have entered into partnerships with the federal government to ensure the continued protection of specific land areas (USDA/DOI 1992). USING LAND MANAGEMENT PLANS The federal government has established systems to update periodically the management plans for lands owned and managed by the federal government (about 263 million hectares, or 650 million acres) (USDA/ DOI 1992). In addition to specially protected (reserved) land, the U.S. government owns and manages another 180 million hectares (450 million acres), including national forests, grasslands, and rangelands. These lands are managed in accordance with resource management plans that attempt to address any reasonable, foreseeable impact on the land and its biological resources. Because these plans consider local factors and are updated periodically, if and when it becomes possible to project the impacts of climate change with reasonable accuracy, these plans will be useful for anticipating site-specific impacts and for developing, analyzing, and implementing adaptive measures specially tailored for those locations. While conservation is the primary goal in the reserved areas, nonreserved lands are managed to promote both the wise use and the conservation of natural resources. The requirements for impact assessments under the National Environmental Policy Act help support conservation efforts. In addition, in 1992 both the U.S. Forest Service and the Bureau of Land Management announced policies that would place greater emphasis on total ecosystem management and thus enhance the resilience of species and habitats to climate change. ADOPTING CONSERVATION LAWS, POLICIES, AND PROGRAMS Because no species exists in isolation, laws that conserve one species, such as the Endangered Species Act, also have helped to conserve broad communities and ecosystems. The United States has about twenty such laws, which have helped build up the populations of several species, including some that are listed as threatened or endangered (e.g., the trumpeter swan and the whooping crane) (USDA/DOI 1992). In addition, all fifty states have endangered species acts. Captive breeding and greenhouse propagation programs are critical to the success of many efforts to save threatened and endangered species. Experience gained with these measures today will help similar measures if they are needed in the future. Similarly, the information contained in germ plasm can help researchers develop strains better adapted to a changed atmosphere and climate. For example, every year the U.S. government's National Plant Germ Plasm System distributes over 230,000 samples of germ plasm to more than one hundred nations. In addition, the American Type Culture Collection maintains over 42,000 strains of microorganisms for use in education and research (USDA/DOI 1992). RESTRICTING POLLUTION The United States spends $130 billion a year to comply with statutes, regulations, and policies that reduce soil, water, and air pollution (USDA/DOI 1992). While the primary focus of these laws is to reduce adverse impacts on human health, they also have contributed to healthier, more resilient ecosystems. These laws have helped reduce concentrations of DDT, PCBs, and other organochlorine contaminants several-fold in the tissues of birds and fish, have reduced their vulnerability to other stresses, and have contributed to the recovery of some species, such as the bald eagle. INVOLVING THE PRIVATE SECTOR To allow for a rapid, effective implementation of adaptive measures, if and when necessary, institutional, legal, and economic frameworks must be flexible. In attempting to develop flexible frameworks, the IPCC recommends considering (1) giving local populations and resource users a stake in conservation and sustainable resource use-e.g., by investing them with clear property rights; and (2) decentralizing, as practicable, decision making on resource use and management, while incorporating mechanisms to ensure consideration of broad, societal interests (IPCC 1990d). About 70 percent of the conterminous United States is privately owned (Daugherty 1991). These owners make decentralized decisions individually, within the constraints of applicable laws and regulations. Clearly they have an economic stake in the continued viability of their natural resources. A corollary to this is that in the United States, active voluntary participation of private owners is critical to the success of any effort dealing with land resources. Voluntary actions include planting trees, providing feed for birds and animals, and participating in land conservation programs, as well as the millions of individual decisions made over the years by farmers and other landowners who have increased the productivity of land use markedly. PROMOTING INTERNATIONAL PROGRAMS The United States supports several international programs to conserve biodiversity and improve the produc tivity of agriculture and forestry in developing nations REDUCING COMMODITY The very success of technological progress in increasing productivity simultaneously increases pressures for the overproduction of crops and other natural resources. While each society has its own reasons for such subsidies, they prevent the realization of the full economic and environmental benefits that could result from technological progress. They also encourage the exploitation of marginal lands and other resources, as well as the overexploitation of nonmarginal areas. As part of the General Agreement on Tariffs and Trade (GATT) negotiations, the United States is attempting to reduce habitat loss by working toward reducing price-support programs in international trade worldwide. Worldwide reduction in such subsidies would help strengthen the free-market economies of both developed and developing nations, because the latter are heavily dependent upon agriculture. In turn, stronger free economies would make both adaptation and sustainable development more affordable and would further reduce environmental degradation. Finally, this would also decrease greenhouse gas emissions in the developed nations by sustaining land-use decisions that would effectively produce multiple benefits for livestock, agriculture, and wooded systems. he National Action Plan is based on a variety of programs and laws that together act to reduce greenhouse gas emissions. The Plan deals with three greenhouse gases: carbon dioxide, methane, and nitrous oxide. It also addresses gases that are precursors to the formation of ozone, another important greenhouse gas. Most (80 percent) of the carbon emissions in the United States are caused by burning fossil fuels to produce energy. Reducing these emissions necessitates reducing the demand for energy services, substituting low-carbon fuels for fuels now being used, improving the efficiency of fossil fuel combustion, or increasing carbon "sinks." All of the actions described in this chapter for reducing net carbon emissions rely on these methods. Methods to reduce methane emissions discussed in this chapter include capture from landfills and coal mines, while the principal improvements leading to reduction of nitrous oxide emissions result from changes in nylon manufacturing processes. One of the key building blocks of the National Action Plan is the National Energy Strategy (DOE 1991a), which includes energy-related aspects of the Clean Air Act Amendments of 1990, the Budget Reconciliation Act of 1990, the Intermodal Surface Transportation Efficiency Act of 1991, the Energy Policy Act of 1992, as well as a host of administrative actions at the federal, state, and local levels. To supplement National Energy Strategy programs, the President has initiated a number of additional actions through the Department of Energy, the Environmental Protection Agency, and other executive branch agencies to reduce greenhouse gas emissions from both the energy sector and other activities. Finally, an increasing number of states are incorporating global climate change policy concerns into legislation, administrative actions, sectoral analyses, and state action plans. U.S. Views on Global Climate Change (DOS 1992) outlined existing U.S. policies and estimated their potential to reduce greenhouse gas emissions. Although the information presented focuses on the year 2000, many of the actions, particularly those affecting energy supply and demand, will have effects well into the twentyfirst century. Most of the research, development, and demonstration programs initiated today will have their greatest impact after 2010. Approaches for Reducing Greenhouse Gases Standards, R&D, and Market Improvements The National Action Plan includes activities for reducing greenhouse gases that are based on a number of approaches that combine the efforts of the public sector (federal, state, and local governments) and the private sector. From the public-sector viewpoint, these approaches can be grouped into four main categories: • Undertaking regulatory actions, including the setting of standards. • Conducting research and development to enhance efficiency, improve supplies, and promote fuel switching. • Creating market enhancements, including developing incentives and providing information. • Encouraging the voluntary adoption of processes and technologies that not only make economic sense but also make environmental sense. The National Energy Strategy relies primarily on advanced technologies and improved energy management practices to help maintain adequate supplies of environmentally benign fuels while reducing energy |