Chapter 6: Impacts and Adaptation The discussion of impacts of climate change in this chapter is based on the U.S. National Assessment in the 2000 NAST Report. This report remains highly controversial, and was, at that time, the subject of considerable debate with regard to it scientific and policy discussions. The most contentious aspects of the report were (1) the use of the most pessimistic projects of potential climate impacts, with little or no discussion of the uncertainties involved in such projections; and (2) the use of global climate models to predict impacts on regional climates within the U.S. Global climate models cannot be used to project changes in regional climate, primarily because of insufficient spatial resolution and their inability to represent regional phenomena such as clouds. As was pointed out when the National Assessment was in review, the regional projections from the two climate models used often provide diametrically opposed projects for regional climate, making it impossible to determine which (or either) is (are) correct. Further, attempts to average the results from the two models are also without scientific basis. Thank you for your attention to these comments. Please contact Peg Gutmann at 313-594-0400 if you have any questions.
Sincerely,
W. M. Kreucher