In the decade prior to the SAR, the preponderance of studies employed methods
and tools largely for the purpose of ascertaining the biophysical impacts of
climate change, usually on a sectoral basis. Thus, the methods included models
and other means for examining the impacts of climate change on water resources,
agriculture, natural ecosystems, or coasts. Such methods have improved with
regard to detection of climate change in biotic and physical systems and produced
new substantive findings. In addition, since the SAR, cautious steps have been
taken to expand the "toolbox" to address more effectively the human
dimensions of climate as cause and consequence of change and to deal more directly
with cross-sectoral issues concerning vulnerability, adaptation, and decisionmaking.
In particular, more studies have begun to apply methods and tools for costing
and valuing effects, treating uncertainties, integrating effects across sectors
and regions, and applying DAFs to evaluate adaptive capacity. Overall, these
modest methodological developments are encouraging analyses that will build
a more solid foundation for understanding how decisions regarding adaptation
to future climate change might be taken.