Assessing the Reliability of Water Resources Systems Under Climate Uncertainty. E. Z. Stakhiv, U.S. Army Corps Institute of Water Resources, Casey Building, 7701 Telegraph Road, Alexandria, VA 22315-3868
The performance of water resources management system can be evaluated under stationary climate using a variety of techniques that provide partial measures of rehability, robustness, resilience, etc. There is considerable climate variability under contemporary conditions and uncertainty in virtually every measure of project outputs -- whether economic, social, or environment. Climate change is expected as a consequence of global warming. The assessment of future impacts, benefits and damages is confounded by a hierarchical cascade of analytical uncertainties, which virtually precludes decision making on the basis of conventional risk-cost principles. Since there is a multiplicity of future possible climate states, with highly uncertain consequences, further compounded by uncertainties in economic estimations of the relative benefits and costs of alternative mitigation strategies. A series of ten case studies were conducted to assess, through sensitivity analysis and rudimentary risk analysis, the likely range of outcomes regarding the performance of water resource systems, and to examine the prospects for formal risk and uncertainty analysis under non-stationary climate states. The overall result would be used to develop a framework for analysis by Corps analysts who design long-lived projects and systems.