Climate change and hydrological response in the trans-state Oologah Lake watershed—comparison between statistical downscaled CMIP3 and dynamical downscaled NARCCAP simulations

The Oologah Lake, located in northeast Oklahoma, provides 50% of potable water for the city of Tulsa and surrounding rural areas. This study focuses on its watershed with area of 4,340 square mile (11,249.7 km2), extending northwestward from the lake and upstream along the Verdigris River and its tributaries to Kansas. Climate change and its impact on the watershed could potentially affect water availability to the lake and cause further problems of water quality, wildlife habitat and fishery degradation. Statistical downscaled projections from BCSD-CMIP3 shows increase of temperature (3 0C) and slight decrease of precipitation for the region in the next 50 years, but with significant uncertainty arising from different GCMs. This study will take use of the VIC model to evaluate the climate change impact on the hydrological system of the watershed by taking into account both statistical and dynamical downscaled projections from CMIP3 and NARCCAP (North American Regional Climate Change Assessment Program). The expected results will assist water resources assessment and risk management decision making by the local and state agencies.