www.adv-geosci.net/5/25/2005/ © Author(s) 2005. This work is licensed under a Creative Commons License. Uncertainties in the simulation of groundwater recharge at different scales 1Research Centre Jülich, Systems Analysis and Technology Evaluation, 52425 Jülich, Germany 2Research Centre Jülich, Agrosphere Institute: ICG IV, 52425 Jülich, Germany Abstract. Digital spatial data always imply some kind of uncertainty. The source of this uncertainty can be found in their compilation as well as the conceptual design that causes a more or less exact abstraction of the real world, depending on the scale under consideration. Within the framework of hydrological modelling, in which numerous data sets from diverse sources of uneven quality are combined, the various uncertainties are accumulated. In this study, the GROWA model is taken as an example to examine the effects of different types of uncertainties on the calculated groundwater recharge. Distributed input errors are determined for the parameters' slope and aspect using a Monte Carlo approach. Landcover classification uncertainties are analysed by using the conditional probabilities of a remote sensing classification procedure. The uncertainties of data ensembles at different scales and study areas are discussed. The present uncertainty analysis showed that the Gaussian error propagation method is a useful technique for analysing the influence of input data on the simulated groundwater recharge. The uncertainties involved in the land use classification procedure and the digital elevation model can be significant in some parts of the study area. However, for the specific model used in this study it was shown that the precipitation uncertainties have the greatest impact on the total groundwater recharge error. Full Article in PDF (PDF, 6583 KB) Citation: Bogena, H., Kunkel, R., Montzka, C., and Wendland, F.: Uncertainties in the simulation of groundwater recharge at different scales, Adv. Geosci., 5, 25-30, 2005. Bibtex EndNote Reference Manager |