Fachbereich Geowissenschaften

Prioritising Major Predictive Uncertainty Sources in Coupled Hydrosystem Models

What are the contributions of parameter, model, and measurement uncertainties to the overall uncertainty of coupled hydrological models?

PhD Researcher: Reynold Chow
Supervisors: Wolfgang Nowak (University of Stuttgart), Thomas Wöhling (TU Dresden), Beth Parker (University of Guelph)

Coupled hydrosystem models (CHMs) can provide useful insight to the hydrological system when used appropriately. However, every model has inherent assumptions and simplifications leading to uncertainty in model predictions. Typically numeric CHMs are used in a deterministic way without rigorous quantification of model output uncertainty. Uncertainty analysis forces the modeller to scrutinize the processes involved when arriving at a modelled result.

To prioritize CHM uncertainty I must first identify the sources of model uncertainty than quantify, normalize, and prioritize (rank) these uncertainty sources. Numeric CHMs have three main inherent uncertainty sources as described by (Gupta et al. 2005), which are:

  • i. Data
  • ii. Parameter
  • iii. Structural or Conceptual

Developing the methodology to create the CHMs and quantify uncertainty is currently a work in progress. With quantifiable measures of model uncertainty, I will prioritize the sources of uncertainty in CHMs and investigate methods to minimize the greatest uncertainty sources. This will ensure that CHMs will be used appropriately and not used in a way that exceed their predictive capacity.


  • Chow, R., Bennett, J.P., Dugge, J., Wöhling, T., Nowak, W. (2019): Evaluating subsurface parameterization to simulate hyporheic exchange: The Steinlach River Test Site. Groundwater, doi: 10.1111/gwat.12884
  • Motavita D.F., Chow R., Guthke A., Nowak W. (2019): The Comprehensive Differential Split-Sample Test: A stress-test for hydrological model robustness under climate variability. Journal of Hydrology, doi: 10.1016/j.jhydrol.2019.03.054
  • Chow, R., Wu, H., Bennett, J.P., Dugge, J., Wöhling, T. and Nowak, W. (2018): Sensitivity of simulated hyporheic exchange to river bathymetry: The Steinlach River Test Site. Groundwater. doi: 10.1111/gwat.12816
  • Chow, R., Frind, M.E., Frind, E.O., Jones, J.P., Sousa, M.R., Rudolph, D.L., Molson, J.W., Nowak, W. (2016): Delineating Baseflow Contribution Areas for Streams – A Model and Methods Comparison. Journal of Contaminant Hydrology, 195, 11-22, doi: 10.1016/j.jconhyd.2016.11.001


"Integrated Hydrosystem Modelling 2018" Conference Poster