C.C.A. Obergfell, M.Sc

PhD Title

Derivation of Groundwater Flow Model Parameters From Time Series Analysis

Objective

The objective of this PhD research project is to derive parameters for groundwater flow models consistent with time series analysis of groundwater level fluctuations.

Since the beginning of the application of modeling to simulate groundwater flow, considerable effort has been dedicated to model calibration and inverse modeling. However, little attention has been paid to the validity of the calibration targets. It is still a common practice to use groundwater levels measured at specific locations as targets without prior time series analysis of the fluctuations dynamics. Such an analysis should tell us what cause the observed fluctuations (precipitation, evaporation, groundwater abstraction) and to which extent.

The idea is then to calibrate groundwater flow models not on measured groundwater levels but on levels simulated with time series models. Alternatively, the characteristic moments of the impulse response functions derived for each stress and at each point could be used as calibration target. In this way, groundwater flow models would not have to explain what they cannot explain, namely the part of the fluctuation which is not attributable to the modeled stresses and boundary conditions. The parameters derived in this way should also result in more consensus about the validity of the groundwater flow model.

Christophe Obergfell, M.Sc

Ph.D. Researcher