HIBAL: a hydrologic-isotopic-balance model for application to paleolake systems

Authors

Larry Benson, University of Colorado at BoulderFollow
Fred Paillet, US Geological Survey

Date of this Version

2002

Citation

Quaternary Science Reviews 21 (2002) 1521–1539

Abstract

A simple hydrologic-isotopic-balance (HIBAL) model for application to paleolake δ¹⁸O records is presented. Inputs to the model include discharge, on-lake precipitation, evaporation, and the δ¹⁸O values of these fluid fluxes. Monthly values of climatic parameters that govern the fractionation of ¹⁸O and ¹⁶O during evaporation have been extracted from historical data sets and held constant in the model. The ability of the model to simulate changes in the hydrologic balance and the δ¹⁸O evolution of the mixed layer has been demonstrated using measured data from Pyramid Lake, Nevada. Simulations of the response in δ¹⁸O to step- and periodic-function changes in fluid inputs indicate that the hydrologic balance and δ¹⁸O values lag climate change. Input of reconstructe driver discharges and their δ¹⁸O values to Pyramid and Walker lakes indicates that minima and maxima in simulated δ¹⁸O records correspond to minima and maxima in the reconstructed volume records and that the overall shape of the volume and δ¹⁸O records is similar. The model was also used in a simulation of abrupt oscillations in the δ¹⁸O values of paleo-Owens Lake, California.