@article{fdi:010075554,
  title = {{U}ncertainty analysis for seawater intrusion in fractured coastal aquifers : effects of fracture location, aperture, density and hydrodynamic parameters},
  author = {{K}oohbor, {B}. and {F}ahs, {M}. and {A}taie-{A}shtiani, {B}. and {B}elfort, {B}. and {S}immons, {C}. {T}. and {Y}ounes, {A}nis},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n this study we use polynomial chaos expansion ({PCE}) to perform uncertainty analysis for seawater intrusion ({SWI}) in fractured coastal aquifers ({FCA}s) which is simulated using the coupled discrete fracture network ({DFN}) and variable-density flow ({VDF}) models. {T}he {DFN}-{VDF} model requires detailed discontinuous analysis of the fractures. {I}n real field applications, these characteristics are usually uncertain which may have a major effect on the predictive capability of the model. {T}hus, we perform global sensitivity analysis ({GSA}) to provide a preliminary assessment on how these uncertainties can affect the model outputs. {A}s our conceptual model, we consider fractured configurations of the {H}enry {P}roblem which is widely used to understand {SWI} processes. {A} finite element {DFN}-{VDF} model is developed in the framework of {COMSOL} {M}ultiphysics ({R}). {W}e examine the uncertainty of several {SWI} metrics and salinity distribution due to the incomplete knowledge of fracture characteristics. {PCE} is used as a surrogate model to reduce the computational burden. {A} new sparse {PCE} technique is used to allow for high polynomial orders at low computational cost. {T}he {S}obol' indices ({SI}s) are used as sensitivity measures to identify the key variables driving the model outputs uncertainties. {T}he proposed {GSA} methodology based on {PCE} and {SI}s is useful for identifying the source of uncertainties on the model outputs with an affordable computational cost and an acceptable accuracy. {I}t shows that fracture hydraulic conductivity is the first source of uncertainty on the salinity distribution. {T}he imperfect knowledge of fracture location and density affects mainly the toe position and the total flux of saltwater entering the aquifer. {M}arginal effects based on the {PCE} are used to understand the effects of fracture characteristics on {SWI}. {T}he findings provide a technical support for monitoring, controlling and preventing {SWI} in {FCA}s.},
  keywords = {{S}eawater intrusion ; {F}ractured coastal aquifers ; {U}ncertainty analysis ; {U}ncertain fracture characteristics ; {G}lobal sensitivity analysis ; {S}obol' ; indices},
  booktitle = {},
  journal = {{J}ournal of {H}ydrology},
  volume = {571},
  numero = {},
  pages = {159--177},
  ISSN = {0022-1694},
  year = {2019},
  DOI = {10.1016/j.jhydrol.2019.01.052},
  URL = {https://www.documentation.ird.fr/hor/fdi:010075554},
}