Role of integrated assessment and scenario development issues beyond SRES

It is already 4 years since the Intergovernmental Panel on Climate Change Special Report on Emission Scenarios (IPCC-SRES) and the IPCC Third Assessment Report (IPCC-TAR) activities indicated the various future emission pathways as well as the possible societal options. In the first decade of the 21st century, international negotiations on global warming mitigation have not progressed as well as expected. There are several possible reasons for this: (1) there are still many scientific uncertainties about climate change, especially regional change, and the warming may be beneficial to some and not to others; (2) there is insufficient knowledge on the impacts of climate change and the adaptation possibilities; and (3) there are difficulties about the assessments of the mitigation strategies in the long term and the spatial distribution. Although the activities of the IPCC have led to the compilation and proposal of extensive scientific findings, the gap between scientific findings and the political decisions remains deep. On the other hand, most nations agree with the importance of energy and environmental conservation as one of the key factors in sustainability. In this context, research on the long-term assessment of global warming should provide the basis for decision making as the comprehensive scientific information to support the dialogues among policy makers and stake holders. This article discusses two issues regarding scenario developments pending in the IPCC-SRES and IPCC-TAR activities: the role of narrative scenarios for the assessment of societal and economic structures, with introduction to our recent research activities and the effects of long-term uncertainties on short-term decisions. Copyright Springer Japan 2006