Postdoctoral position: Numerical modeling of the interactions between vadosezone hydrology and shallow water-table fluctuations, including hysteresis anddynamic effects.

Applications are invited for a 18-months postdoctoral position atCemagref (http://www.cemagref.fr) in partnership with the EcoleNationale des Ponts et Chaussées (http://www.enpc.fr).

This position is offered as the outcome of the Cooperative ResearchAction DYNAS funded by INRIA(http://www-rocq.inria.fr/estime/DYNAS/). The project aimed atdeveloping software tools using physically-based models and robustnumerical methods to simulate the dynamics of shallow water-tables invariably saturated porous media.

Vadose (or unsaturated) zone has been identified as one of the mostcomplex parts of the hydrologic cycle. In particular, the transitiondomain between unsaturated and saturated (water-table) regions of thesoil profile is a highly sensitive zone for water and solutestransport from the top soil to the ground water. Sometimes defined asthe “Capillary Fringe”, this domain is subjected tohigh-frequency variable conditions such as wetting-dryingcycles. These variations impact significantly the vadose zonehydrology especially when the water-table is close to soil surface andis likely to fluctuate. This situation is very common in near-streamhumid areas or in artificially subsurface drained systems.

The postdoctoral research will pursue the following objectives :
- Review the appropriate literature to define a precise numericalmodeling strategy;
- Contribute to integrate hysteresis and dynamic effects in numerical codes ofCemagref and/or Cermics/ENPC.
- Define test-cases to benchmark the various numerical tools;
- Investigate, numerically, the impacts of hysteresis and dynamic effects forvarious soil types and transient boundary (and initial) conditions;
- If possible, calibrate and validate the model(s) with existing experimentaldata from lab experiments;
- Write a couple of scientific articles, to be submitted tohigh-ranking journals.

The candidate should have, or receive shortly, a Ph.D. in the field of appliedmathematics, scientific computing, or computational fluid dynamics and arelevant experience in computer programming. A background in the modeling ofsubsurface flows or connected physical processes is advisable.

The position will be for 18 months starting in January or February 2006. Thepostdoctoral fellowship is approximately 1800/month net and includes basichealth insurance. The candidate will be located at the Cemagref HBAN ResearchUnit, in Antony, 15 km south from Paris, and will interact frequently with theCermics and Cereve laboratories on ENPC Campus in Marne la Vallée (20 km eastfrom Paris).

Candidates should submit by e-mail (pdf format preferred) or by post a coverletter in support of the application, a curriculum vitae with a list ofpublications, one to three publications, and name and addresses of 3references.

The material should be sent by October 15th 2005 to
Dr.Cyril KAO
Cemagref, HBAN
Parc de Tourvoie, BP 44
92163, Antony Cedex, FRANCE
cyril.kao@cemagref.fr