Regional climate change impacts and freshwater systems: focusing the adaptation research agenda

Regional climate models can provide useful insights for research on water-sector adaptation to climate change. Results are presented from a RegCM2 study that investigates the effect of a doubling of atmospheric carbon dioxide upon climate for a domain centred over California. By the expected time of doubling, 2060, results show generally increasing surface temperatures, altered precipitation patterns, and reduced average annual snow accumulation. Two rankings of institutional scale – hierarchies of control and longevity before revision – are then presented to help identify appropriate directions for policy research. The goals are to: 1) tightly link possible adaptations with climate change impacts, and 2) match time-scales of climate change impacts with timescales of institutional change. Two examples of possible research programmes are identified: re-engineering north-coast river systems and securing southcoast water imports. Each research programme responds to the results of the RegCM2 study in terms of both the nature and the time-frame of the impacts.