Climate change and water resources planning criteria

Global climate change has become an important area of investigation in the social and natural sciences and engineering, and water resources has often been cited as an area in which global climate change may be particularly important for decision-making. This volume contributes to the practice of climate change impact assessment and the more difficult and politically contentious process of evaluating adaptation options. It should contribute also to the next round of national climate assessments and action plans that are required under the terms of various international agreements and to the third UN Intergovernmental Panel on Climate Change scheduled to begin in 1998. Moreover, as governments and institutions move rapidly from the decade-long assessment phase of understanding the problems and issues into the decision making phase, this volume should be useful to policymakers interested in confronting the choices and tradeoffs involved in water resources planning and management. In contrast to the considerable work that has been devoted to examining the potential impacts of global climate change on water resources systems, relatively little has been done to review the adequacy of existing water planning principles and evaluation criteria and related impact procedures in the light of these potential changes. Moreover, the absence of a uniform understanding and application of basic assessment and evaluation principles makes it difficult to synthesize the numerous climate change impact analyses and hinders the prospects for developing an integrated assessment to account for the linkages and feedbacks among the climate, socioeconomic factors, ecosystems, and atmospheric chemistry. This volume is designed as a first step in considering whether and how water resources planning principles and evaluation criteria should be altered in view of the potential impacts of anthropogenically-induced global climate change. The work reported here can be seen against the background of the development of U.S. water resources planning criteria and the current international efforts (led by the IPCC, among others) to evaluate the significance of, and appropriate responses to, climate change. This volume is divided into four sections. Part I includes this introduction and the next two papers, which present the background on global climate change and water resources, and survey water resources and climate change assessment methods. Part II examines theoretical issues such as the int