Article (Scientific journals)
Assessment of conceptual model uncertainty for the regional aquifer Pampa del Tamarugal – North Chile
Rojas, Rodrigo; Batelaan, Okke; Feyen, Luk et al.
2010In Hydrology and Earth System Sciences, 14, p. 171-192
Peer Reviewed verified by ORBi
 

Files


Full Text
publi183-2009.pdf
Author preprint (2.94 MB)
Download

The officila publication can be found on the web site of 'Hydrology and Earth System Sciences' An Interactive Open Access Journal of the European Geosciences Union.


All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
uncertainty; groundwater flow modelling; Pampa del Tamarugal Aquifer; Generalized Likelihood Uncertainty Estimation (GLUE); Bayesian Model Averaging (BMA); conceptual model uncertainty
Abstract :
[en] In this work we assess the uncertainty in modelling the groundwater flow for the Pampa del Tamarugal Aquifer (PTA) – North Chile using a novel and fully integrated multimodel approach aimed at explicitly accounting for uncertainties arising from the definition of alternative conceptual models. The approach integrates the Generalized Likelihood Uncertainty Estimation (GLUE) and Bayesian Model Averaging (BMA) methods. For each member of an ensemble M of potential conceptualizations, model weights used in BMA for multi-model aggregation are obtained from GLUE-based likelihood values. These model weights are based on model performance, thus, reflecting how well a conceptualization reproduces an observed dataset D. GLUE-based cumulative predictive distributions for each member of M are then aggregated obtaining predictive distributions accounting for conceptual model uncertainties. For the PTA we propose an ensemble of eight alternative conceptualizations covering all major features of groundwater flow models independently developed in past studies and including two recharge mechanisms which have been source of debate for several years. Results showed that accounting for heterogeneities in the hydraulic conductivity field (a) reduced the uncertainty in the estimations of parameters and state variables, and (b) increased the corresponding model weights used for multi-model aggregation. This was more noticeable when the hydraulic conductivity field was conditioned on available hydraulic conductivity measurements. Contribution of conceptual model uncertainty to the predictive uncertainty varied between 6% and 64% for ground water head estimations and between 16% and 79% for ground water flow estimations. These results clearly illustrate the relevance of conceptual model uncertainty.
Disciplines :
Geological, petroleum & mining engineering
Author, co-author :
Rojas, Rodrigo;  Katholieke Universiteit Leuven - KUL > Department of Earth and Environmental Sciences > Applied Geology and Mineralogy
Batelaan, Okke;  Vrije Universiteit Brussel - VUB > Hydrology and Hydraulic Engineering
Feyen, Luk;  DG-Joint Research Centre (JRC) > Institute of Environment and Sustainability > Land management and natural hazards unit
Dassargues, Alain  ;  Université de Liège - ULiège > Département Argenco : Secteur GEO3 > Hydrogéologie & Géologie de l'environnement
Language :
English
Title :
Assessment of conceptual model uncertainty for the regional aquifer Pampa del Tamarugal – North Chile
Publication date :
2010
Journal title :
Hydrology and Earth System Sciences
ISSN :
1027-5606
eISSN :
1607-7938
Publisher :
European Geosciences Union, Katlenburg-Lindau, Germany
Volume :
14
Pages :
171-192
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 18 November 2009

Statistics


Number of views
164 (14 by ULiège)
Number of downloads
202 (6 by ULiège)

Scopus citations®
 
54
Scopus citations®
without self-citations
50
OpenCitations
 
49

Bibliography


Similar publications



Contact ORBi