Collaborative Research: The role of temporally varying specific storage on confined aquifer dynamics

随着气候变化、人口增长和工业化加剧了水资源短缺的普遍性，获得清洁饮用水继续成为人们日益关注的问题。为了应对日益减少的地表水供应，许多地区转向从被称为含水层的多孔岩石或沉积物中取水，这些岩石或沉积物含有世界上大部分的液态淡水。承压含水层通常较深且受压，储存着世界含水层中大部分的淡水。在人类活动（如抽水）和气候变化的影响下，预测承压含水层的储水量是增加、减少还是保持不变，对于保护含水层以供未来使用至关重要，但一直具有挑战性。承压含水层储水量的变化通常是通过一个称为储水量的参数来估计的，该参数是通过乘以井中测量的水位变化来获得的。在这个项目中，研究人员将确定储水量如何随空间和时间变化，以及对储水量的准确估计如何帮助科学家和工程师准确估计含水层的储水量，并提高我们有效管理地下水使用的能力。在承压含水层中，储水量会随时间发生显著变化，如果假设储水量不变，传统地下水模型的预测就会不准确。黏土层的压实，可以从卫星上观察到，引起了储层性的变化。如果存在粘土，假设蓄水能力是恒定的，可能会导致对含水层补给的过于乐观的估计，如果在管理实践中实施，可能会导致含水层迅速枯竭。在这项研究中，研究人员将为犹他州的帕罗万山谷开发地下水模型，这是一个地下水利用受到良好限制的地区，与世界上其他高利用的含水层有相似之处。他们将开发两种类型的模型，(1)假设恒定储存性的传统模型，以及(2)允许储存性随时间变化的更强大的模型，并将模型的性能与井测量和卫星数据进行比较。通过这项研究，科学家们将量化随时间变化的储水量对含水层储水量的影响，并有助于改善对补给和含水层参数（如水力导电性）的估计。在项目期间，他们将与社区利益相关者合作，并在研究和科学传播方面培训研究生和本科生。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Access to clean drinking water continues to be a growing concern as climate change, population growth and industrialization increase the prevalence of water scarcity. In response to dwindling surface water supply, many regions turn to water from porous rocks or sediments known as aquifers that hold most of the world’s liquid freshwater. Confined aquifers, which are typically deep and pressurized, hold the majority of freshwater in the world’s aquifers. Predicting whether water storage in a confined aquifer will increase, decrease, or remain constant given variations in human activity such as pumping, and climate change is critical for preserving aquifers for future use, but has been challenging to estimate. Changes in confined aquifer storage are typically estimated by a parameter known as storativity, which is obtained by multiplying changes in water levels measured in wells. In this project, the researchers will determine how storativity changes over space and time, and how accurate estimation of storativity can help scientists and engineers to accurately estimate aquifer storage, and improve our ability to effectively manage groundwater use. In confined aquifers, storativity can vary significantly over time, leading to inaccurate predictions in traditional groundwater models if the storativity is assumed constant. The compaction of clay layers, which can be observed from satellites, causes changes in storativity. If clays are present, assuming that storativity is constant can lead to overly optimistic estimates of aquifer recharge which, if implemented in management practices, could result in rapid aquifer depletion. In this research, the investigators will develop groundwater models for the Parowan Valley in Utah, a region with well-constrained groundwater use, and that shares similarities with other high-use aquifers of the world. They will develop two types of models, (1) traditional models that assume constant storativity, and (2) more robust models that allow storativity to vary with time and compare the model performance against well measurements and satellite data. Through this research, scientists will quantify the effect that time-varying storativity has on aquifer storage, and contribute to improving estimates of recharge and aquifer parameters such as hydraulic conductivity. During the project, they will collaborate and work with community stakeholders, and train graduate and undergraduate students in both research and science communication.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.