Yeo Howe Lim, University of North Dakota, Department of Civil Engineering

Abstract: A research project on modeling the water level series of Devils Lake, a terminal lake in North Dakota, is presented. The goal of the project is to predict the future scenarios of the water level regime under various climate change conditions. The research involved calibrating a coupled rainfall-runoff and reservoir model using data from both ground gage stations and NASA Satellite observations. The project has proven the feasibility of using spatially distributed GCM data in generating runoff from the sub-basins using a well calibrated hydro-climatic model. Being in a cold temperate region, the process of snowmelt, evaporation and seepage associated with the lake and overland areas were accounted in a continuous reservoir model. In the course of the research, a temperature-based evaporation prediction model was also developed to allow simulation of future evaporation estimations based on the generated temperature series. Future lake level series were simulated using the weather samples obtained from several downscaled GCM runs under varying scenarios due to anthropogenic modifications and the resulting composition of the atmosphere. The annual peak volumetric values transformed from the peak values of simulated water-level traces are analyzed to obtain water level quantiles. The Bulletin 17B recommended LP3 method along with Gaussian/Normal, Lognormal and Gamma/Pearson Type 3 distribution are also applied for comparison purposes. The assembled modeling tool can be used as an integral part of a decision-support system for planning future flood mitigation measures in similar lake bodies with input data derived from both ground stations and NASA Satellites observations.