Executive Summary

Over the past decade, scientific research has greatly advanced the understanding of global environmental change. Research supported through the U.S. Global Change Research Program (USGCRP) is providing answers to important questions about the Earth system, how it is changing, and the implications of global change for society.

The USGCRP is focusing research on four key areas of Earth system science that are of significant scientific and practical importance. These priority environmental science issues are:

  1. Seasonal to Interannual Climate Variability -- The USGCRP plays a leading role in an ongoing global endeavor to develop and enhance prediction of seasonal and interannual climate variability. These forecasts are used for economic planning and development in climate-sensitive sectors such as agriculture, water supply, and public health.

  2. Climate Change Over Decades to Centuries -- The USGCRP supports research to reduce uncertainties associated with prediction of long-term climate change and is broadening research to understand and assess the impacts of climate change on natural resources, public health, and socio-economic sectors.

  3. Changes in Ozone, UV Radiation, and Atmospheric Chemistry -- Through USGCRP-supported research, emissions of CFCs from human activities have been unambiguously identified as the cause of the Antarctic ozone hole. Projections that large increases in CFC emissions would lead to large losses of stratospheric ozone underlie the agreement to phase out CFC use. Observations of declining CFC growth rates demonstrate the efficacy of the policies adopted to protect the ozone layer.

  4. Changes in Land Cover and in Terrestrial and Aquatic Ecosystems -- The USGCRP supports research to inventory the current land cover of the Earth and to document changes; to improve understanding of the dynamics of land-cover and land-use change and how terrestrial and aquatic ecosystems react to change; and to document and understand chemical, physical, and biological processes in the oceans and their relationship with the carbon cycle and marine life.

To provide the basis for continuing advancement in scientific understanding and leadership in global change research, the USGCRP continues to support a number of integrative and cooperative efforts, which contribute in varying degrees to all of the priority environmental science issues. These efforts include:

Over the next decade, global change research can further benefit society by promoting sustainable economic development. Research challenges to accomplish this include:



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