Speaker
Mr
Jawher Kerrou
(University of Neuchatel)
Description
Worldwide, seawater intrusion and salinisation of coastal aquifers and soils is a
major threat for food production. While the physico-chemical processes triggering the
transport and accumulation of salts in these regions are relatively well known and
well described by a set of partial differential equations, often it is extremely
difficult to model accurately these phenomena because of the lack of an accurate data
set. On one hand the physical parameters (porosity, permeability, dispersivity) that
control groundwater flow are extremely variable in space within geological media and
are only measured at some specific locations, on the other hand the forcing terms
(pumping, precipitation, etc.) are often not measured directly in the field. The
result is a high level of uncertainty. The problem is how to take rational decision
toward sustainable water management in such a context ?
One possibility explored within this work is to run a large set of model simulations
with stochastic parameters by means of the EGEE GRID infrastructure and to define
robust and sustainable water management decisions based on probabilistic analysis of
the resulting simulation outputs. This approach is currently being investigated in
the Cape Bon peninsula, located 50 km South-East of Tunis, one of the most productive
agricultural areas in Tunisia. In this plain the World Bank has shown that major
water resources problem could occur in the next decade. One of the major sources of
uncertainty in the Cap Bon aquifer system are the pumping rates and their time
evolution. To investigate the impact of this source of uncertainty, first a
geostatistical model of the spatial distribution of the pumping has been constructed
and then the GRID has been used to run a 3D density-dependent groundwater flow and
salt transport model in a Monte Carlo framework.
While these results are still preliminary, GRID computing paradigm offers clearly a
huge potential within this field. One particularly interesting aspect offered by this
methodology to Tunisian water managers, not having access to local computing
technology, is to be able in a near future to run directly, via a web portal to the
GRID, their groundwater flow simulation and uncertainty analysis. This option has not
been tested yet and requires further development.
Primary author
Mr
Jawher Kerrou
(University of Neuchatel)
Co-authors
Dr
Giuditta Lecca
(CRS4)
Mr
Giuseppe La Rocca
(University of Catania)
Prof.
Philippe Renard
(University of Neuchatel)
Dr
Roberto Barbera
(University of Catania)
