What timeframe did the National Assessment address?
The National Assessment emphasized the potential consequences over the next 25-30 years, and also over the next 100 years. Analyses of potential consequences over the next 100 years considered the potential for significant secular changes in climate, potentially accompanied by changes in climate variability and the frequency of extreme events, as well as the projected large changes in atmospheric carbon dioxide concentrations. Over this time frame, coping technologies and practices were expected to change, so some provision was made in the analyses for these considerations. Analyses of potential consequences over the 25-30 years were needed to consider that atmospheric carbon dioxide concentrations would certainly continue to rise, and that there might be modest, but observable, trends in climate. Potential consequences over both short and long time frames were needed to consider the possibility of non-linear and threshold responses.
