In the first joint activity of such scope, many nations of the world have established the Global Change Research Program (GCRP). Scientists and policy-makers around the world have met regularly for more than two decades to establish priorities for data acquisition that will help answer many of the questions we face. Members of the Intergovernmental Panel on Climate Change (IPCC) composed a list of seven major geophysical and biological phenomena to monitor. All signatories to the GCRP are addressing these phenomena in one way or another. These seven prioritized areas are:

• Water and Energy Cycles
• Oceans
• Chemistry of the Troposphere and Lower Stratosphere
• Land Surface Hydrology and Ecosystem Processes
• Glaciers and Polar Ice Sheets
• Chemistry of the Middle and Upper Stratosphere
• Solid Earth

Those nations that are technologically capable work together to design instruments and spacecraft and to define data-gathering needs to make this large-scale examination of our planet as efficient as possible. To that end, scientists from one nation may design and build instruments, while a group from another nation designs and builds the spacecraft. Other parties establish data policies that allow the free flow of data across international (political) and physical boundaries.

The principal players —(nations and organizations) are:

• Canada
• Committee on Earth Observation Satellites (CEOS)
• European Space Agency (ESA)
• EUMETSAT (European Meteorological Satellite organization)
• France
• Germany
• International Council of Scientific Unions (ICSU)
• International Geosphere-Biosphere Program (IGBP)
• Intergovernmental Panel on Climate Change (IPCC)
• Italy
• Japan
• United Kingdom
• United Nations Environmental Program (UNEP)
• United Nations/World Meteorological Organization (UN/WMO)
• United States of America
• World Climate Research Program (WCRP)

The job is so large that no group or nation alone can address it properly. Collaboration is an absolute requirement if we are to do the job properly.

In response to its agreement to participate in the GCRP, the executive branch of the US government established roles for several federal agencies in the USGCRP.

Those agencies and their roles include:

National Aeronautics and Space Administration (NASA): responsible for space-based Earth science observations, and studies of broad scientific scope that examine the planet as an integrated whole;

National Science Foundation (NSF): promotes basic research in all areas of terrestrial, solid Earth, atmospheric, and oceanic sciences;

National Oceanic and Atmospheric Administration (NOAA): maintains a balanced program of observations, analytical studies, climate prediction, and information management;

Department of Energy (DOE): focuses on carbon dioxide and other emissions from energy supply and end-use systems;

US Department of Agriculture (USDA): conducts research to assess the effects of global change on the agricultural food and fiber production systems and on forests and forest ecosystems of the U.S. and worldwide;

Department of Defense (DoD): conducts mission-related research into environmental processes and conditions that affect defense operations, tactics, and systems;

Department of the Interior (DOI): addresses the collection, maintenance, analysis, and interpretation of short- and long-term land, water, biological, and other natural resources information;

Department of Transportation (DOT): assesses the impact of transportation primarily through the use of fossil fuels on global change;

Environmental Protection Agency (EPA): conducts research to assess, evaluate, and predict the ecological, environmental, and human health consequences of global change.