The U.S. Global Change Research Program (USGCRP) has responsibilities to observe, document, and understand global change and to predict it to the extent possible. The USGCRP does this by concentrating on five science areas: seasonal-to-interannual variability, decadal-to-centennial variability, atmospheric chemistry and ultraviolet-B radiation, ecosystems, and human dimensions—areas described in the previous chapters.
By far the largest share of USGCRP funding goes to making observations to accomplish both the aims of the science areas and those of observing and documenting global change.
This chapter constitutes the link between the scientific foundation established in Chapter 2, Chapter 3, Chapter 4, Chapter 5, Chapter 6 through Chapter 7 and the course of action now required.
The scientific foundation for each of the six primary science areas—biology and biogeochemistry of ecosystems, seasonal-to-interannual climate change, decadal-to-century climate change,
atmospheric chemistry, paleoclimate, and the human dimension of global change consists of a statement of the following: scientific character of the problem, selected case studies, key unanswered scientific questions, lessons learned in the course of scientific research over the past decades, and research imperatives.
