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Introduction The Purpose and Scope of this Report The purpose of this document is to provide an initial re- search strategy to guide planning and conduct of the U.S. Global Change Research Program. This strategy will be expanded into a more detailed and comprehensive U.S. Global Change Research Program plan in 1989. The comprehensive research plan will present the details of the U.S. Global Change Research Program, including evaluat- ing how well the current activities address the key scientific questions and program goals, identifying the gaps in know- ledge and the priorities among research needs, and defining individual Federal agency roles. Specifically, this research strategy report will: â¢ present the overall program goals, objectives, budget, and key scientific questions; â¢ identify the important national and international global change studies and organizations; â¢ summarize the research plan and implementation strategy; and â¢ inventory the current U.S. Federal agencies' research activities. This research strategy has been developed in close collabo- ration with other national and international planning groups and activities, including the National Academy of Sciences, the International Geosphere-Biosphere Programme, and the pro- grams outlined in the five year plan of the National Climate Program. What is Global Change? Manifestations of global change are numerous and com- plex: volcanic activity, widespread desertification on some continents, the dramatic changes in many mid-latitude forests
over the past several centuries, changing water tables in numer- ous regions, earthquakes, the retreat of glaciers, the accumula- tion of "greenhouse" gases and ozone-depleting chemicals in the atmosphere, the appearance of the Antarctic "ozone hole", acidification of some soils and lakes, and the reduction in genetic diversity of animals and plants. The earth system is very dynamic and these changes occur on all time and geographic scales. The Earth itself holds testimony of ancient steaming bogs and crushing ice sheets, variations far beyond those known to modern civilization. Many of these changes are the result of a variety of inter- related natural processes, including changes in the climate system, in solar processes, in the earth's orbit, in volcanic pro- cesses, and in the distribution of biological species and land masses that may have been ongoing for centuries. Although human activities may have the potential to alter the earth system, it is clear that variations occur naturally over a wide range. The broad study of all of these interrelated earth pro- cesses constitutes global change research. What is Man's Role in Changing the Environment? Most humans experience changes as seasonal-to-decadal regional weather and climate changes (e.g., last summer's drought). For this reason these changes, and the influences that human activities might have on them, have dominated public concern. In the past, policymakers have understandably fo- cused on needs perceived as the most immediate, such as weather forecasting, urban smog, and acid rain. In recent years, the attention of both scientists and poli- cymakers has extended to more global-scale, longer-term changes, such as the question of global warming which may occur when additional heat radiated from the earth is trapped by increases in atmospheric "greenhouse" gases.
Although there are many other "greenhouse" gases, carbon dioxide (CO2), generated by natural processes and by the burning of wood, coal, oil, gasoline, and natural gas, is cur- rently believed to be the most important contributor to global warming because of its long atmospheric lifetime and ability to trap heat. CO2 concentration in the atmosphere has increased by 25% over the past two centuries. Part of this increase is a by-product of energy consumption and deforestation to meet human needs. However, global warming has occurred in pre-industrial eras. The potential for future global warming, and the relative contributions of natural processes and human influences are still poorly known. A better scientific understanding of these changes and an improved predictive capability are important elements of the U.S. Global Change Research Program. Why is Reliable Global Change Prediction Important? The effects of natural variability and human activity in the global system can have profound economic, environmental, social, and national security implications. For example, the single 1982-1983 "El Nino" event caused billions of dollars in economic losses worldwide, and this natural fluctuation in the climate system is known to be a recurring event of varying magnitude and periodicity. Potential changes accompanying a global warming trend might have even greater impact on regional temperature re- gimes and precipitation patterns. These could result in changes in agricultural policies, modes of energy production and usage, utilization and protection of natural resources, and coastal-zone management. Reliable estimates of the magnitude and rate of these changes would be needed at many decision levels within society: individuals (e.g., farmers), industry (e.g., energy pro- ducers), and governments (e.g., regulators).