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. **

最近认识到气候和水文学的非平稳性，因此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，许多水居住在高纬度地区，那里的流域建模能力和精度受到稀疏的水文气象网络的阻碍，其密度低于世界计量组织的最低测量网络标准。这项研究致力于通过一种创新的同位素-水文耦合方法，为加拿大北部地区开发改进的水文预报工具。事实证明，同位素流量耦合测量在追踪与气候或土地利用非平稳性有关的逐步下游水文变化方面特别有用。在限制水文模型参数范围方面，同位素也是有用的诊断变量，但通常只有在有观测数据的情况下才临时应用。拟议的计划重点是创新和发展等水流量模型，这是一个完全分布式的水文模型，模拟和引导水同位素在区域景观中的路线。提出了IsoWATFLOOD模型的主要创新，通过纳入雪和融雪动力学以及用于蒸发模拟和蒸散分配的氚同位素，增强了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验证内部水文过程对径流的贡献的手段，改善了模拟的水文过程的真实性，并确保了适当的水文气候反馈。连续模拟这两种同位素还具有填补大流域观测到的同位素记录空白的优势，并有可能在未来气候下进行同位素信号预测。该模型将利用现有的同位素数据集(Mackenize和Low Nelson Rivers)在加拿大的两个泛北极盆地进行测试。将制作理论(模拟)同位素框架，以验证蒸发和蒸散分配。改进的积雪融化动态模拟将显著改进年度水平衡模拟，因为积雪融化代表着这些盆地每年最大的流量。研究将为新的工具和总部基地提供水文模拟方面的专门培训，目的是在不增加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、规划和建设进行径流预测的部门以及大坝结构的重新认证将受到影响，因为需要对极端径流事件进行估计，但不再由测量记录表示。成果适用于加拿大研究人员和水资源从业者，他们需要先进的工具来协助气候变化下的径流预测。**