Development of an innovative coupled isotope-hydrologic model for large Canadian watersheds

为加拿大大型流域开发创新的同位素耦合水文模型

• 批准号: RGPIN-2016-06043
• 负责人: Stadnyk, Tricia
• 金额: $ 0.32万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=670356
• 关键词: Development; innovative; coupled; isotope; hydrologic

Recent recognition of non-stationarity in climate, and consequently hydrology, is requiring more advanced watershed models to project changes in future runoff and the impacts to Canada's water supply and therefore security. In Canada, much of the water resides at high latitudes where watershed modelling capabilities and accuracies are hindered by sparse hydro-meteorological networks, with densities below World Metrological Organization minimum gauging network standards. This research endeavours to develop improved hydrologic prediction tools for northern Canadian regimes through an innovative coupled isotope-hydrometric approach. Coupled isotope-discharge measurement has proven particularly useful in tracing progressive downstream hydrologic change related to climate or land-use non-stationarity. Isotopes are also useful diagnostic variables in constraining hydrologic model parameter ranges, but have typically been applied ad-hoc only when and where observational data is available. The proposed program focuses on innovation and development of the isoWATFLOOD model, a fully distributed hydrological model that simulates and routes water isotopes across regional landscapes. Key innovations of the isoWATFLOOD model are proposed to enhance applicability to high-latitude, remote basins by incorporating snow and snowmelt dynamics and the deuterium isotope for evaporation modelling and evapotranspiration partitioning. Simulation of the isotope tracers provides a means to validate internal hydrologic process contributions to streamflow, improving the realism of simulated hydrographs and ensuring proper hydroclimatic feedbacks. Continuous simulation of both isotopes also has the advantage of gap-filling' observed isotope records in large river basins, and the potential for isotope signal projection under future climates. The model will be tested in two pan-arctic Canadian basins with existing isotope datasets (Mackenize and lower Nelson Rivers). Theoretical (simulated) isotope frameworks will be produced to validate evaporation and evapotranspiration partitioning. Improved simulation of snowmelt dynamics will significantly improve annual water balance simulations since snowmelt represents the largest flow volume on an annual basis for these basins. Research will provide new tools and HQP with specialized training in hydrologic simulation, with the goal of improving simulation in large rivers without additional field instrumentation. Sectors requiring streamflow projection for infrastructure design, planning, and construction in the North, and recertification of dam structures will be impacted as estimates of extreme flow events are required but no longer represented by gauged records. Outcomes are intended for Canadian researchers and water practitioners requiring advanced tools to assist in streamflow projection under climate change. **

最近人们认识到气候和水文学的非平稳性，需要更先进的流域模型来预测未来径流的变化以及对加拿大供水和安全的影响。在加拿大，大部分水位于高纬度地区，流域建模能力和准确性受到稀疏水文气象网络的阻碍，其密度低于世界计量组织最低计量网络标准。 这项研究致力于通过创新的同位素-水文耦合方法为加拿大北部地区开发改进的水文预测工具。事实证明，耦合同位素排放测量对于追踪与气候或土地利用非平稳性相关的下游渐进水文变化特别有用。 同位素在限制水文模型参数范围方面也是有用的诊断变量，但通常仅在可获得观测数据的时间和地点临时应用。拟议项目的重点是 isoWATFLOOD 模型的创新和开发，这是一个完全分布式的水文模型，可以模拟和引导跨区域景观的水同位素。 isoWATFLOOD 模型的关键创新之处在于，通过将雪和融雪动力学以及用于蒸发建模和蒸散分配的氘同位素结合起来，增强对高纬度偏远盆地的适用性。同位素示踪剂的模拟提供了一种方法来验证内部水文过程对水流的贡献，提高模拟水文过程线的真实性并确保适当的水文气候反馈。两种同位素的连续模拟还具有填补大型河流流域中观测到的同位素记录的空白以及未来气候下同位素信号预测的潜力的优势。该模型将在现有同位素数据集的两个泛北极加拿大盆地（马肯尼兹河和尼尔森河下游）进行测试。 将产生理论（模拟）同位素框架来验证蒸发和蒸散分配。 改进融雪动力学模拟将显着改善年度水平衡模拟，因为融雪代表了这些流域每年最大的流量。研究将为水文模拟方面的专门培训提供新工具和 HQP，目标是在无需额外现场仪器的情况下改进大河流的模拟。需要对北方基础设施设计、规划和建设进行流量预测的部门以及大坝结构的重新认证将受到影响，因为需要对极端流量事件进行估计，但不再由测量记录来表示。 结果旨在为需要先进工具来协助气候变化下的水流预测的加拿大研究人员和水从业人员提供。 **