Monday, May 7, 2012
Proper characterization of climate is essential for long-term groundwater management and planning. Climate is known to have a profound impact on groundwater availability as it not only impacts the amount of groundwater that is used by humans but also affects recharge, evapotranspiration and surface-water groundwater fluxes. Long-term regional groundwater planning endeavors, such as the groundwater management area joint planning required in the state of Texas, must therefore properly account for climatic influences as part of the planning process. The characterization of future climates is inherently uncertain and there is a growing recognition that past climate behaviors may not be representative of future climates. Therefore, understanding differences between historical climate observations and future climatic projections and their potential impacts on groundwater management is vital. In addition, given the large-scale variability, it is imperative that a suitable decision support framework be established to evaluate suitable groundwater management options under climate change uncertainty. The primary goal of this study is to demonstrate the utiltiy of two-person zero sum game theory to evaluate groundwater management options under climate variability. The game theoretic model is developed by treating nature as one of the players whose moves are characterized by different states of nature. These states of nature are developed by a comprehensive statistical analysis of dendrochronologic data that reconstructs historical precipitation and temperature patterns as well as considering bias-corrected spatially downscaled projections obtained from general circulation models (GCMs). The decision support system seeks to obtain groundwater management policies (i.e., how much groundwater can be safely extracted with minimal ecological impacts and maximal economic gains) that are robust under a variety of plausible future climates.