Paper No. 12
Presentation Time: 11:45 AM
USING NUMERICAL MODELING TO EXPLORE THE POTENTIAL EFFECTS OF CLIMATE CHANGE ON GROUNDWATER/SURFACE WATER SYSTEMS, FOULD'S CREEK WATERSHED, CHEQUAMEGON-NICOLET NATIONAL FOREST, WI
PRUITT, Aaron H., Department of Geoscience, University of Wisconsin, 1215 W Dayton St, Madison, WI 53706, BRADBURY, Kenneth R., Wisconsin Geological and Natural History Survey, University of Wisconsin-Extension, Madison, WI 53705, BAHR, Jean M., Department of Geoscience, University of Wisconsin-Madison, 1215 W. Dayton St, Madison, WI 53706, JUCKEM, Paul F., U. S. Geological Survey, Wisconsin Water Science Center, 8505 Research Way, Middleton, WI 53562, HIGGINS, Dale, USDA-Forest Service, Chequamegon-Nicolet National Forest, 1170 S 4th Ave, Park Falls, WI 54552 and HUNT, Randall J., Wisconsin Water Science Center, U.S. Geological Survey, 8505 Reaseach Way, Middleton, WI 53562, ahpruitt@wisc.edu
Understanding how a changing climate might affect water resources is critical for long-term management of forested areas. One method for understanding the impacts of changing climate is to develop numerical models of representative hydrologic systems and then use these models to simulate future scenarios. We are simulating the Fould’s Creek watershed, a small (~33 km^2) forested watershed in till and outwash over crystalline Precambrian bedrock in the Chequamegon-Nicolet National Forest in northern Wisconsin. The Fould’s Creek watershed is an attractive study area in which to test this methodology because it contains multiple first-order streams with either groundwater dominated flow or surface-runoff dominated flow, allowing us to see how different types of streams under the same conditions respond to climate shifts.
We are currently collecting water level, stream flow, and chemistry data from groundwater and surface water that will provide calibration targets for steady state and transient versions of the model. We are developing rating curves for each of the stream segments in the watershed to give us a continuous record of flow throughout the year. To constrain groundwater and surface or shallow subsurface runoff components of stream flow we are using oxygen-18 and deuterium ratios, as well as end member mixing of major ions. Once we have a fully calibrated model, we will use precipitation and temperature outputs from the downscaled climate models from the Wisconsin Initiative on Climate Change Impacts (WICCI) to drive transient versions of the model. We will use the modeling to determine shifts in the timing of peak flows and amount of flows in each of the various stream types, as well as shifts in the contribution of groundwater to the streams.
