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Island groundwater resources often form freshwater lenses overlying saline groundwater. When water is withdrawn from a freshwater lens by a pumping well, saline groundwater migrates upwards toward the well. This vertical seawater intrusion process, also called saltwater upconing, is a major concern when managing well fields. Freshwater lenses of island aquifers have been described as being more vulnerable than continental coastal aquifers, since vertical migration distances associated with upconing are shorter than horizontal ones (Jiao &

Résumé. L'objectif du travail est de fournir aux professionnels de la filière viticole deséléments objectifs sur la pertinence d'une stratégie collective de communication environnementale sur les vins d'AOC, de tester la pertinence d'une segmentation des consommateurs selon leur niveau d'implication vis-à-vis du vin et vis-à-vis de l'environnement, de mesurer l'interaction perçue par les consommateurs entre AOC et environnement selon le niveau de notoriété des AOCLe travail aété mené sur 4 annéesà partir d'enquêtes réalisées sur internet et sur les réseaux sociaux auprès de 3500 consommateurs français. Les résultats obtenus permettent de montrer des différences de perception par les consommateurs sur le lien entre « catégories de vins » et « production respectueuse de l'environnement »Globalement les vins d'AOC sont perçus comme significativement plus respectueux de l'environnement par rapport aux vins d'IGP eux-mêmes mieux perçus que les vins de France. Par ailleurs la réputation d'une AOC peut avoir une influence sur la perception du respect environnemental. Enfin pour les consommateurs, l'impact de la région viticole semble plus important que la réputation d'une AOC quantà « l'image environnementale perçue ». Ce travail permet de donner deś eléments d'analyse sur la perception des consommateurs vis-à-vis des lienséventuels entre signes de qualité et production respectueuse de l'environnement. Il semble clair dans le cas de la filière viticole française que l'usage de messages environnementaux commeélément de différenciation et compétitivité pour les vins d'AOC ne répond pasà une attente de la majorité des consommateurs.Abstract. The objective of this work is to provide for professionals of the wine sector objective elements on the relevance of a strategy of environmental communication in PDO wines and to measure the interaction perceived by the consumers between PDO and environment according to itslevel of notoriety. The work was undertaken between 2012 and 2015 starting from x-ray groups and 3700 surveys conducted into Internet and the social networks. The results got clear differences in perception by the consumers on the link between "categories of wines" and "respectful production for the environment". Overall the wines of PDO are perceived like significantly more respectful for the environment than the better perceived wines of IGP, themselves better percieved than the wines of France. In addition, the reputation of aPDO can affect the perception of the environmental respect For the consumers, the impact of the wine region seems more important than the reputation of a PDO as for "the perceived environmental image" It seems clear in the case of the French wine sector than the use of environmental messages as element of differentiation and competitiveness for the wines of PDO does not answer waiting of the majority of the consumers.

Abstract. In coastal zones, a major objective of groundwater management is often to determine sustainable pumping rates avoiding well salinization. Understanding how model and climate uncertainties affect optimal management solutions is essential to provide groundwater managers information about salinization risk, and is facilitated by the use of optimization under uncertainty (OUU) methods. However, guidelines are missing for the widespread implementation of OUU in real-world coastal aquifers, and for the incorporation of climate uncertainty into OUU approaches. An ensemble-based OUU approach was developed, considering parameter, observation and climate uncertainty, and was implemented in a real-world island aquifer in the Magdalen Islands (Quebec, Canada). A sharp-interface seawater intrusion model was developed using MODFLOW-SWI2 and a prior parameter ensemble was generated, containing multiple equally plausible realizations. Ensemble-based history matching was conducted using an iterative ensemble smoother and yielded a posterior parameter ensemble conveying both parameter and observation uncertainty. 2050 sea level and recharge ensembles were generated and incorporated to generate a predictive parameter ensemble conveying parameter, observation and climate uncertainty. Multi-objective OUU was then conducted, aiming to both maximize pumping rates and minimize probability of well salinization. As a result, the optimal tradeoff between pumping and probability of salinization was quantified, considering parameter, historical observation and future climate uncertainty simultaneously. The multi-objective, ensemble-based OUU led to optimal pumping rates that were very different from a previous deterministic OUU, and close to the current and projected water demand for risk-averse stances. Incorporating climate uncertainty in the OUU was also critical since it reduced the maximum allowable pumping rates for users with a risk-averse stance. The workflow used tools adapted to very high-dimensional, nonlinear models and optimization problems, to facilitate its implementation in a wide range of real-world settings.

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<p>In coastal areas, seawater intrusion is a main driver of groundwater salinization and numerical models are widely used to support sustainable groundwater management. Sharp interface models, in which mixing between freshwater and seawater is not explicitly simulated, have fast run times which enable the implementation of parameter estimation and uncertainty analysis. These are essential steps for decision-support modeling, however their implementation in sharp interface models has remained limited. Few guidelines exist regarding which observations to use, and what processing and weighting strategies to employ. We developed a data assimilation framework for a regional, sharp interface model designed for management purposes. We built a sharp interface model for an island aquifer using the SWI2 package for MODFLOW. We then extracted freshwater head observations from shallow wells, pumping wells and deep open wells, and observations of the seawater-freshwater interface from deep open wells, time-domain electromagnetic (TDEM) and electrical resistivity tomography (ERT) surveys. After quantification of measurement uncertainties, parameter estimation was conducted with PEST and a data worth analysis was carried out using a linear approach. Model residuals provided insight on the potential of different observation groups to constrain parameter estimation. The data worth analysis provided insight on these groups’ importance in reducing the uncertainty of model forecasts. Overall a satisfying fit was obtained between simulated and observed data, but observations from deep open wells were biased. While observations from deep open wells and geophysical surveys had a low signal-to-noise ratio, parameter estimation effectively reduced predictive uncertainty. Interface observations, especially from geophysical surveys, were essential to reduce the uncertainty of model forecasts. The use of different types of observations is discussed and recommendations are provided for future data collection strategies in coastal aquifers. This framework was developed in the Magdalen Islands (Quebec, Canada) and could be carried out more systematically for sharp interface seawater intrusion modeling.</p>

<p>Numerical models and optimization algorithms can be valuable tools for decision-making in coastal and island aquifers, where pumping wells are threatened by salinization. Yet, the implementation of pumping optimization under uncertainty remains limited in practice, because of long simulation times and challenges associated with uncertainty propagation through series of models. A method was developed to optimize pumping rates in an island freshwater lens considering parameter, observation, and climate uncertainty. It was implemented in an island aquifer in the Magdalen Islands (Québec, Canada). A seawater intrusion model with rapid simulation times was developed using MODFLOW-SWI2. The iterative ensemble smoother algorithm implemented by PESTPP-IES allowed for history matching and nonlinear uncertainty quantification. The model predictive uncertainties were coupled with climate uncertainties, including recharge uncertainty (derived from various global circulation models and emission scenarios) and sea-level rise uncertainty. Using PESTPP-OPT, the pumping rates in the freshwater lens were then maximized while avoiding the risk of well salinization and considering parameter, observation, and climate uncertainty. Results of the pumping optimization were compared with estimates of water demand uncertainty. This study used widely available, model-independent software and could be used to support groundwater management decision-making in other insular or coastal areas.</p>