Prior uncertainty investigation of density-viscosity dependent joint transport of heat and solute in alluvial sediments

Joint heat and solute tracer tests allow to add diffusion and conduction information to the solute advection-dispersion and help imaging preferential pathways in heterogeneous aquifers. We perform a joint interpretation of heat and solute tracer tests combining deterministic modeling and Bayesian Evidential Learning. The results show a strong influence of the water viscosity. The stochastic simulations highlight the influence of spatial and parameter uncertainty on the resulting breakthrough curves, stressing the need for realistic uncertainty quantification.Joint heat and solute tracer test inversion for imaging preferential pathway

A Kolmogorov-Smirnov type test for shortfall dominance against parametric alternatives

This paper proposes a Kolmogorov-type test for the shortfall order (also known in the literature as the right-spread or excess-wealth order) against parametric alternatives. In the case of the null hypothesis corresponding to the Negative Exponential distribution, this provides a test for the new better than used in expectation (NBUE) property. Such a test is particularly useful in reliability applications as well as duration and income distribution analysis. The theoretical properties of the testing procedure are established. Simulation studies reveal that the test proposed in this paper performs well, even with moderate sample sizes. Applications to real data, namely chief executive officer (CEO) compensation data and flight delay data, illustrate the empirical relevance of the techniques described in this paper.Right-spread order; Excess-wealth order; New better than used in expectation; Bootstrap; Reliability; CEO compensation; Flight delay

Une autre foi, une autre France. Les libelles imprimés par les catholiques zélés durant les guerres de Religion (1585-1629)

Une autre foi, une autre France. Les libelles imprimés par les catholiques zélés durant les guerres de Religion (1585-1629) part de l’hypothèse selon laquelle il est possible d’écrire une autre histoire des guerres de Religion françaises, conflits dont l’essence est l’affrontement armé entre catholiques et protestants et dont l’historiographie classique situe le terme définitif en 1598 à la faveur l’édit de Nantes. Elle entend montrer que cette période troublée mais extrêmement riche a aussi connu le conflit à l’intérieur de la mouvance catholique, à travers l’écrit et sans rupture majeure entre 1585 et 1629. Ces recherches doctorales ont par conséquent poursuivi le triple objectif de faire un pas de côté par rapport au récit classique des guerres de Religion, de reconstituer une intense guerre de papier mais aussi de cerner l’action et l’identité d’un groupe méconnu : les catholiques zélés. Dédiée à des libelles, courts documents généralement imprimés, cette thèse part des textes pour y revenir sans cesse : à la confluence de l’histoire de la pensée politique, de l’analyse du discours et de l’analyse des réseaux, elle montre quelles ressources textuelles ont été mobilisées afin de défendre quelles idées, et quels liens il est possible de tisser entre ces pratiques et le contexte politique reconstitué le plus finement possible. 319 libelles sont étudiés à travers quatre chapitres dont les premiers correspondent à trois pics de production de ce type d’écrits : la Ligue (1585-1594), la fin de la minorité de Louis XIII (1614-1615) et les guerres de Rohan (1620-1629). Un quatrième et dernier chapitre, dédié à l’arsenal discursif des libellistes zélés, étudie une sélection des processus textuels les plus significatifs de l’activité polémique catholique durant les guerres de Religion. Cette thèse met en lumière la richesse d’un discours et l’action d’un groupe social, politique et religieux spécifique. Elle identifie une série de procédés discursifs (amalgame des adversaires, polarisation par exclusion de l’ennemi, jeu sur la menace, exploitations variées des techniques de mise en page et des frontières entre politique et fiction…) et d’idées (soumission du roi à Dieu, nécessité d’une guerre contre l’hérésie, inscription des conflits du présent dans une histoire sainte…) propres aux catholiques zélés. À travers ces résultats, cette thèse précise la complexité, la richesse et la fécondité des conflits politico-religieux de la fin du XVIe siècle et du début du XVIIe siècle. Elle contribue aussi à démontrer le caractère multiple du camp catholique à cette époque en identifiant précisément les ressorts par lesquels, au sein de cette mouvance, un groupe se constitue discursivement contre d’autres

Désigner le scandale. Le paratexte des pamphlets catholiques entre accusation et légitimation (France et Pays-Bas habsbourgeois, 1579 1590)

peer reviewe

Report on the tracer tests (experimental setup, results and interpretation)

Tracer experiments were performed in the Brévilles test site in order to highlight vertical variations in groundwater fluxes related to vertical variations hydraulic conductivity, to estimate contaminant travel time from several locations in the catchment to the springs and to identify transport processes affecting the fate of solutes in the saturated part of the aquifer. Following a first tracer experiment with uranine and sulforhodamine G in 2003, four tracer injections were performed in November 2005 in different piezometers, using uranine, sulforhodamine B, iodide and lithium. Tracer concentrations were monitored in the injection wells and at the basin outlet (spring and gauging station). Using the FVPDM method, concentration evolutions monitored in the injection wells allowed one to estimate local Darcy fluxes. At the basin outlet, only two tracers were recovered. Analyses of breakthrough curves confirm the stratification of the aquifer with more permeable levels in the lower part. They also suggest the probable occurrence of vertical interactions within the aquifer.AquaTerra - Integrated Modelling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global chang

Assessing the effects of spatial discretization on large-scale flow model performance and prediction uncertainty

Large-scale physically-based and spatially-distributed models (>100 km2) constitute useful tools for water management since they take explicitly into account the heterogeneity and the physical processes occurring in the subsurface for predicting the evolution of discharge and hydraulic heads for several predictive scenarios. However, such models are characterized by lengthy execution times. Therefore, modelers often coarsen spatial discretization of large-scale physically-based and spatially-distributed models for reducing the number of unknowns and the execution times. This study investigates the influence of such a coarsening of model grid on model performance and prediction uncertainty. The improvement of model performance obtained with an automatic calibration process is also investigated. The results obtained show that coarsening spatial discretization mainly influences the simulation of discharge due to a poor representation of surface water network and a smoothing of surface slopes that prevents from simulating properly surface water-groundwater interactions and runoff processes. Parameter sensitivities are not significantly influenced by grid coarsening and calibration can compensate, to some extent, for model errors induced by grid coarsening. The results also show that coarsening spatial discretization mainly influences the uncertainty on discharge predictions. However, model prediction uncertainties on discharge only increase significantly for very coarse spatial discretizations.Peer reviewe

Investigating the respective impacts of groundwater exploitation and climate change on wetland extension over 150 years

International audiencePeatlands are complex ecosystems driven by many physical, chemical, and biological processes. Peat soils have a significant impact on water quality, ecosystem productivity and greenhouse gas emissions. However, the extent of peatlands is decreasing across the world, mainly because of anthropogenic activities such as drainage for agriculture or groundwater abstractions in underlying aquifers. Potential changes in precipitation and temperature in the future are likely to apply additional pressure to wetland. In this context, a methodology for assessing and comparing the respective impacts of groundwater abstraction and climate change on a groundwater-fed wetland (135 km2) located in Northwest France, is presented. A groundwater model was developed, using flexible boundary conditions to represent surface-subsurface interactions which allowed examination of the extent of the wetland areas. This variable parameter is highly important for land management and is usually not considered in impact studies. The model was coupled with recharge estimation, groundwater abstraction scenarios, and climate change scenarios downscaled from 14 GCMs corresponding to the A1B greenhouse gas (GHG) scenario over the periods 1961-2000 and 2081-2100. Results show that climate change is expected to have an important impact and reduce the surface of wetlands by 5.3-13.6%. In comparison, the impact of groundwater abstraction (100% increase in the expected scenarios) would lead to a maximum decrease of 3.7%. Results also show that the impacts of climate change and groundwater abstraction could be partially mitigated by decreasing or stopping land drainage in specific parts of the area. Water management will require an appropriate compromise which encompasses ecosystem preservation, economic and public domain activities

Assessment of nitrate trend in groundwater using a regional scale approach

editorial reviewed6. Clean water and sanitatio