GLOBAL OBSERVATION SYSTEMS It is essential that long-term, comprehensive regional and global observations are collected, archived, and analyzed in order to advance scientific understanding of the entire Earth system and to develop a deeper comprehension of its components and the interactions among them. The USGCRP has a coordinated program of many land-, ocean-, airborne-, and satellite-based systems that measure and monitor different facets of the Earth system in an integrated observational strategy.
A comprehensive global observing system enhances the ability to understand and predict the effects of many parts of the Earth system. These include:
- Hydrologic and dynamic processes, which control the Earth's temperature and the formation, maintenance, and dissipation of clouds and their interactions with solar radiation.
- Biogeochemical processes, which contribute to the formation, transport, and fate of trace gases and aerosols and their global distributions.
- Climatological processes, which govern the interactions of land and ocean surfaces with the atmosphere through the transport of water, heat, mass, and momentum.
- Geophysical processes, which have shaped and continue to modify the Earth's surface through volcanism and the melting of glaciers and ice sheets.
The USGCRP is participating in developing an international observation program to support measurements and research on atmospheric clouds, aerosols, water vapor, radiation budgets, and ozone, as well as on critical ocean and land parameters important to global change. The most comprehensive observation system in the USGCRP is the space-based Earth Observing System (EOS), which is being planned and implemented by U.S. scientists in cooperation with other nations. When implemented, following a series of launches scheduled between 1998 and 2014, EOS will consist of a series of polar-orbiting and low-inclination satellites providing global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans for a minimum of 15 years. EOS will greatly enhance the ability to understand and predict the dynamics of many parts of the Earth system (see Critical Measurements to be Made by EOS and EOS and Associated International Satellites and Mission Objectives). Other space- based sensors include weather satellites, satellites that measure ozone and other atmospheric chemicals, satellites that record global sea level with unprecedented accuracy, and radar systems that can observe the Earth's surface through cloud cover in order to record topography, soil moisture, sea-ice dynamics, and ocean temperatures.
Space-based observations are complemented by surface-based systems that measure key Earth-system parameters such as greenhouse gases, aerosols, ozone, ultraviolet radiation, and critical variables of ocean-atmosphere-land system interactions. The U.S. collaborates with many nations to operate an extensive array of ocean monitoring instruments. An interagency UV monitoring network has been developed to provide intercalibrated UV data nationwide (see Interagency Cooperation). Atmospheric concentrations of greenhouse gases and ozone-depleting substances are monitored through an informal worldwide network of in situ and flask-sampling sites. The U.S. also is developing a plan to establish a network of sites for long term observations and research on terrestrial and marine ecological systems. Existing USGCRP ecological observation systems are being considered for inclusion in this network.
THE GLOBAL CHANGE DATA AND INFORMATION SYSTEM Global change research activities generate and require massive amounts of highly diverse data and information to document, understand, model, and assess global change. A major focus for data and information management efforts within the USGCRP is the development of the Global Change Data and Information system (GCDIS). The development of GCDIS is being coordinated with related activities within the U.S. Government, including those of the Federal Geographic Data Committee and the emerging National Information Infrastructure, in particular with the Government Information Locator Service. GCDIS will provide the infrastructure of the global change data and information management program. The GCDIS is a priority-driven system composed of individual agency systems made interoperable by the use of common standards and approaches, technology sharing, and data policy coordination. The GCDIS functions include setting priorities for individual data and information sets, identifying and/or developing those sets, and incorporating them and the necessary related service into GCDIS. The USGCRP recently published the U.S. Global Change Data and Information System Implementation Plan.
GCDIS will also include a number of long-term, retrospective data sets that are critical for evaluating climate variability and for use in detecting global changes. These data sets include global data from historical marine meteorological observations, upper air observations, global and regional variations of temperature and precipitation, oceanographic observations, and baseline studies on atmospheric trace constituents, including aerosols and ozone. Retrospective data sets from Landsat, for example, have been invaluable for studying global land-cover change.
The Earth Observing System Data and Information System (EOSDIS), a component of GCDIS, is being built in an evolutionary manner to support launch of EOS platforms. EOSDIS is beginning to provide data sets through its Distributed Active Archive Centers (DAACs). Improvements scheduled for l996 will provide faster, more comprehensive user services and links to other global change data sets. EOSDIS is also providing access to existing long-term satellite data sets (Pathfinder data). Data from other major research programs, such as the Atmospheric Radiation Measurement (ARM) program, are being incorporated as a component of GCDIS.
RESEARCH ON THE HUMAN DIMENSIONS OF GLOBAL CHANGE AND TOOLS FOR CONDUCTING INTEGRATED ASSESSMENTS
As knowledge about the dynamics of global change increases, greater emphasis in the USGCRP has been placed on research on fundamental social and behavioral processes related to environmental change. U.S. research on the human dimensions of global change is coordinated with related efforts in other nations through the framework of the international Human Dimensions of Global Environmental Change Programme (HDP). Within the U.S., fundamental research is conducted on the economic, demographic, social, institutional, geographic, and human health-related aspects of global change. Attention is given to the processes through which human activities affect natural systems and the ways that humans respond to changing natural conditions. Among the most important forms of human-environmental interaction are transformations of the land surface, the product of the interaction between human land uses and natural processes that also alter land cover.
In addition to providing important understanding about the complex ways that human and natural systems interact with each other, USGCRP research has developed new tools and approaches to assist decision makers in thinking about global change. Several programs have supported the development and use of methods and models for integrated assessment of global change. Integrated assessments are a new approach for examining the complex interactions among the Earth's physical, biological, and human systems. Integrated assessments involve the effective linkage of quantitative models and other representations of different systems in ways that permit evaluation of the impacts of changes in one system on other systems. In addition to providing valuable information about the dynamics of change, integrated assessments can provide national and international decision makers in government and the private sector with a framework for identifying and evaluating the likely consequences of different alternatives. Among the topics on which research has focused are the development of rigorous modeling approaches that link physical, biological, and socioeconomic systems; meta-analyses of models and data; and the treatment of uncertainty and risk in integrated systems.
Human dimensions research also has focused on the processes, methodological tools, and formal models fundamental to the creation, implementation, and evaluation of environmental policies and other kinds of decisions. Among the methodological issues on which research has focused are the availability and reliability of data on human systems; the use of expert judgments in decision making; economic valuation of environmental resources; measures of sustainability; indicators of environmental quality; and the extraction of generalized relationships from case studies. Research projects also have examined the processes through which problems are identified and responses are outlined, implemented, and evaluated. Among the studies falling in this category are investigations of technological innovation and diffusion and the processes of international environmental negotiations.
GLOBAL CHANGE EDUCATION AND COMMUNICATION An important goal of the USGCRP is to enhance knowledge about the state of the Earth system and the changes which are expected to occur. To achieve this goal, the USGCRP assists in training future scientists through supporting undergraduate, graduate and post- doctoral research, as well as through the development of teacher- training and curricular materials for K-12 educators. The USGCRP also sponsors public education efforts to provide people with scientific information about global environmental issues. Traditional education methods have been expanded to focus on multimedia communication and recognition of the complex interdisciplinary nature of global change science.
The most important functions of interagency cooperation in global change education and communication are the encouragement of activities to educate and inform the public of progress in scientific research that increases human knowledge of society and its Earth- system interactions. Specific elements of the strategy used to achieve this objective are to continue involvement of teachers and the general public in both formal and informal education activities through regionally focused programs; to emphasize an interactive approach to education through hands-on computational and experimental activities; and to continue supporting fellowships in undergraduate and graduate education to prepare the next generation of scientists. The education program also encourages the use of high-speed communications technologies to communicate new knowledge, and it promotes the dissemination of federal data and information on global change.
In addition, the USGCRP has established the Global Change Research Information Office (GCRIO) "to disseminate to foreign governments, businesses, and institutions, as well as citizens of foreign countries, scientific research information available in the United States which would be useful in preventing, mitigating, or adapting to the effects of global change," as called for in the 1990 Global Change Research Act. GCRIO also provides extensive information services to citizens and institutions within the United States.