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• Observed heads, salinities, & retrieved SWI length from ERT data used in calibration. • Parameter estimation reduced the uncertainty in salinity predictions. • Quantifying uncertainty in SWI extent was performed using OLHS linked with NSMC. • Fixing identified parameters, OLHS & filtering technique reduced computational cost. • Identifying pumping fields threatened by SWI in 2050, Wadi Ham aquifer, UAE. Uncertainty in environmental modeling predictions, stemming from parameter estimation, is a crucial challenge that must be addressed to ensure effective decision-making. Limited field measurements, high computational costs, and a lack of guidance in estimating measurement uncertainty further compound this challenge, particularly for highly parameterized complex models. In this study, we propose a novel and computationally efficient framework for quantifying predictive uncertainty that can be applied to a range of environmental modeling contexts. The novel components of the framework include efficient parameter space sampling using an Optimized Latin hypercube sampling strategy, and applying the Null Space Monte Carlo method (NSMC) along with a developed filtering technique. The NSMC generates sample sets to calibrate the model while exploring the null space. This space contains parameter combinations that are not sufficiently supported by observations. The filtering technique omits low-potential parameter sets from undergoing model calibration. The framework was tested on the seawater intrusion (SWI) model of Wadi Ham aquifer in the United Arab Emirates (UAE) to investigate aquifer sustainability in 2050. Our results demonstrate the importance of incorporating direct and indirect measurements of heads, salinity, and geophysical survey data into the calibration dataset to reduce uncertainty in salinity predictions. The extent of SWI for multiple calibrated parameter sets varied by 4.5% to 11% relative to their means at two main pumping fields. We conclude, with a moderate to a high degree of certainty, that SWI is a serious threat to these fields, and actions are needed to protect the aquifer from salinization. Additionally, variations in SWI length under different geological conditions illustrate regions of high uncertainty that require further data collection. Our framework effectively reduced and quantified prediction uncertainty and provides decision-makers with critical information to inform risk management strategies. [ABSTRACT FROM AUTHOR]

In this study the vulnerability of the Wadi Ham aquifer, located in the Fujairah Emirate of the UAE, to seawater intrusion (SWI) is assessed using a 3D finite element (FE) model. The numerical model is developed based on available hydrogeological data in real scale. By simulation of the aquifer for the next 10 years and by maintaining the current rates of pumping (in year2015), the progress of seawater intrusion in year 2025 is followed by further depletion in freshwater storage of the Wadi Ham aquifer. In order to control this problem, the model is subjected to a management strategy involving surface recharge of the aquifer with treated wastewater. [ABSTRACT FROM AUTHOR]

Purpose |!|#8211; Seawater intrusion represents a major problem in many coastal aquifers all over the world. It degrades the water-quality and hence the groundwater may become unsuitable for domestic and agriculture purposes. Due to the direct hydraulic contact between the freshwater and saline water in coastal aquifers and the density difference between the two water bodies, the seawater migrates inland. The problem is exacerbated when the groundwater abstraction rates exceed the natural recharge from rainfall events. The key to controlling this problem is to maintain the proper balance between water being pumped from the aquifer and the amount of water recharging it. The purpose of this paper is to present a coupled transient finite element model for simulation of fluid flow and solute transport in soils with application to study seawater intrusion in coastal aquifers. Design/methodology/approach |!|#8211; The model includes coupling of fluid flow and solute transport. Transient density-dependent flow and the dependency of dispersion on velocity are considered. After validation, the model is applied to predict the seawater intrusion in the Wadi Ham aquifer, UAE in vertical sections and the results are compared with those from a commercial code (SEWAT) which was used to simulate seawater intrusion in the aquifer in a horizontal section. Findings |!|#8211; A good agreement is observed between the results of the current model in the vertical cross-section and those of SEWAT in the horizontal cross-section for the case of Wadi Ham. The results show that the model can predict the extent of seawater intrusion (and the transition zone) and distribution of salt concentration in the aquifer with a good accuracy. Originality/value |!|#8211; The developed model includes coupling of fluid flow and solute transport in saturated and unsaturated porous media. Transient density-dependent flow and the dependency of dispersion on velocity are considered. The model has been applied to a real world case study. A combination of the results in vertical and horizontal sections has been used to build a 3D picture of seawater intrusion in the aquifer. [ABSTRACT FROM AUTHOR]

Groundwater pumping from Kalbha and Fujairah coastal aquifer of the United Arab Emirates (UAE) has increased significantly during the last two decades to meet the agriculture water demands. Due to the lack of natural replenishment from rainfall and the excessive pumping, groundwater levels have declined significantly causing an intrusion of seawater in the coastal aquifer of Wadi Ham. As a result, many pumping wells in the coastal zone have been terminated and a number of farms have been abandoned. In this paper, MODFLOW was used to simulate the groundwater flow and assess the seawater intrusion in the coastal aquifer of Wadi Ham. The model was calibrated against a five-year dataset of historical groundwater levels and validated against another eleven-year dataset. The effects of pumping on groundwater levels and seawater intrusion were investigated. Results showed that reducing the pumping from Khalbha well field will help to reduce the seawater intrusion into the southeastern part of the aquifer. Under the current groundwater pumping rates, the seawater will continue to migrate inland. [ABSTRACT FROM AUTHOR]

Background and Objectives: Eating disorders (ED) can be influenced by psychological and socio-cultural factors. The aim of this study was to explore the association between parental and media influences and body image concerns as factors in the onset of ED.Methods and Study Design: A cross-sectional study was conducted among 662 students (407 women and 255 men) attending one of three universities in United Arab Emirates (UAE). The study employed an online self-administered questionnaire with validated scales: Eating Attitudes Test-26 (EAT-26), Body Shape Questionnaire (BSQ), Media Influences Scale, and Family Influences Scale (FIS).Results: About 33% of the sample had EAT- 26 scores >=20 and 45% showed mild to marked concerns about their body shape. Women students were significantly more concerned about their shape, and more influenced by media than men. There were significant differences in the means of all scores, except for media influence, among the four BMI groups. The EAT-26 score showed strongest correlation with BSQ (r=0.48), followed by FIS, Media and BMI (r=0.419, r=0.276 and r=0.18 respectively). The BSQ was the best predictor of ED and was inversely associated with the EAT-26 score (B=-1.51, OR=0.219, 95% CI: 0.152-0.316, p<0.001).Conclusions: The findings of this study indicate that ED and body shape concerns are highly prevalent among the university student sample, and highlight the strong influence that both the media and families exert on the development of ED among young adults. These findings provide baseline data for future longitudinal studies to investigate factors influencing ED. [ABSTRACT FROM AUTHOR]