David Tarboton

 

Modeling the Hydrology of the Great Salt Lake: What makes the Great Salt Lake go up and down?

The Great Salt Lake is a closed basin lake in which level and volume fluctuate due to differences between inflows and outflows.  The only outflow is evaporation, which depends directly on lake area and salinity, both of which depend on lake volume.  The lake’s level, volume and area adjust to balance, on average, precipitation and streamflow inflows by evaporation.  This presentation will describe the hydrology of the Great Salt Lake, examining the sensitivity of lake volume changes to precipitation, streamflow and evaporation and the interactions among these processes and lake area and salinity related to volume.  A statistical model is used to simulate representative realizations of future climate and streamflow inputs.  Climate and salinity are used to compute salinity adjusted evaporation from the lake.  These then drive a mass balance model of the lake that projects volume, area and salinity and quantifies the sensitivity of the lake to changes in inputs, due to fluctuations in climate as well as development in the watershed, and withdrawals for mineral extraction.  Our findings show that variability in lake level and volume are dominated by variability in streamflow inputs and the area dependence of evaporation volume, with smaller sensitivities to precipitation directly on the lake, salinity and withdrawals.  These provide a context for understanding future fluctuations in lake level that impact the lake ecosystem, economy and environment.

David Tarboton is a professor of Civil and Environmental Engineering, Utah Water Research Laboratory, Utah State University. He received his Sc.D. and M.S. in Civil Engineering (Water Resources and Hydrology) from the Massachusetts Institute of Technology and his B.Sc Eng in Civil Engineering from the University of Natal in South Africa. His research and teaching are in the area of surface water hydrology. His research focuses on advancing the capability for hydrologic prediction by developing models that take advantage of new information and process understanding enabled by new technology. He has developed a number of models and software packages including the TauDEM hydrologic terrain analysis and channel network extraction package that has been implemented in parallel, and a snowmelt model. He is lead on the National Science Foundation HydroShare project to expand the data sharing capability of Hydrologic Information Systems to additional data types and models and to include social interaction and collaboration functionality. His work on the Great Salt Lake has examined the hydrology, relating precipitation, stream inflow and evaporation to lake volume, area and level. He is a member of the American Geophysical Union, American Society of Civil Engineers, American Water Resources Association and is a Registered Professional Engineer (Utah).
500 Years ago by Charles Uibel

500 Years ago by Charles Uibel