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USGS · 70011273

Estimation of groundwater recharge parameters by time series analysis

Richard L. Naff·Allan L. Gutjahr
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Abstract

A model is proposed that relates water level fluctuations in a Dupuit aquifer to effective precipitaton at the top of the unsaturated zone. Effective precipitation, defined herein as that portion of precipitation which becomes recharge, is related to precipitation measured in a nearby gage by a two-parameter function. A second-order stationary assumption is used to connect the spectra of effective precipitation and water level fluctuations. Measured precipitation is assumed to be Gaussian, in order to develop a transfer function that relates the spectra of measured and effective precipitation. A nonlinear least squares technique is proposed for estimating parameters of the effective-precipitation function. Although sensitivity analyses indicate difficulties that may be encountered in the estimation procedure, the methods developed did yield convergent estimates for two case studies.

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Richard L. Naff, Allan L. Gutjahr. 2010-07-09. Estimation of groundwater recharge parameters by time series analysis. https://doi.org/10.1029/wr019i006p01531

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