Simple automatic time-stepping for improved simulation of groundwater hydrographs
Jackson, Christopher R.. 2012 Simple automatic time-stepping for improved simulation of groundwater hydrographs. Ground Water, 50 (5). 736-745. 10.1111/j.1745-6584.2011.00898.xFull text not available from this repository. (Request a copy)
An automatic time-stepping algorithm is presented, based on the intensity of driving groundwater recharge, that improves the simulation of groundwater level fluctuations in regional models while maintaining model run-times. The algorithm is implemented in the ZOOMQ3D finite difference groundwater flow code and controls the discretization of time using two user-defined criteria: a maximum time-step length and a maximum recharge per time-step. Daily recharge is accumulated in time until either of these criteria is violated when the model then calculates a solution. The efficiency and accuracy of the algorithm is tested using an idealized groundwater model and an existing regional groundwater model of a UK aquifer. The approach is illustrated using simulations of high groundwater levels and associated groundwater flood events in a responsive, high-diffusivity aquifer. Simulations using the automatic time-stepping technique are presented that reduce the maximum absolute error in groundwater level by 45% and the run-time by 51% compared to models using conventional, a priori defined stress-periods and time-steps.
|Programmes:||BGS Programmes 2010 > Groundwater Science|
|Additional Keywords:||GroundwaterBGS, Groundwater, Groundwater modelling|
|Date made live:||13 Sep 2012 13:29|
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