How much selection and calibration of hydrological models influence climate change impact and adaptation conclusions?

水文模型的选择和校准对气候变化影响和适应结论有多大影响？

• 批准号: 391616-2009
• 负责人: Anctil, François
• 金额: $ 4.78万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2010
• 资助国家: 加拿大
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=464843
• 关键词: How; much; selection; calibration; hydrological

There is a large consensus in the scientific community that one must already envisage adaptation to climate change. In hydrology, the assessment of the impacts of changing climate demands the combined usage of three elements. First, climate projections are generated for long simulation time periods by global circulation models (GCMs), coupled to ocean and sea ice models, on a domain that covers the globe. Then a downscaling technique reconciles the scale mismatch between the large-scale climatic models and the watershed scale the most important scale for water management. Finally, a hydrological model simulates future watershed outflows. If lots of efforts have already targeted reducing the uncertainty of the first two components of such systems, little quantitative knowledge is as yet available about the role of hydrological model complexity. This study thus aims filling part of that gap by seeking an answer to the following: How much the selection and calibration of hydrological models influence climate change impact and adaptation conclusions? In particular, the project will implement twenty-two hydrological models on four river systems to evaluate the influence of the selection of a potential evapotranspiration formulation and the importance of pertinent hydrologic model parameter identification. Improper parameter selection may lead to a model that does not behave as the natural system it is seeking to simulate, while climate change may push potential evapotranspiration formulations beyond their calibration range. Four future climate projections will be used in the proposed study, the objective being to cover a wide range of plausible future temperatures and precipitations. The evaluation and comparison process will not only be based on typical hydrological scores and water balance components, it will also make use of real dam management applications as a complementary evaluation mean. Moreover, large differences in simulation will be analysed by looking in detail at the model structures. All this work aims improving Canada's ability for a timely adaptation of its water management schemes.

科学界有一个很大的共识，那就是人们必须已经预见到对气候变化的适应。在水文学中，评估气候变化的影响需要综合使用三个要素。首先，气候预测是由全球环流模型(GCM)在覆盖全球的区域上与海洋和海冰模型相结合产生的长模拟时间段的预测。然后，一种降尺度技术协调了大尺度气候模型和流域尺度之间的尺度失配，流域尺度是水资源管理的最重要尺度。最后，一个水文模型模拟未来的分水岭外流。如果许多努力已经着眼于减少这类系统的前两个组成部分的不确定性，那么关于水文模型复杂性的作用，迄今几乎没有定量的知识可用。因此，这项研究旨在通过寻求以下问题的答案来填补这一空白：水文模型的选择和校准对气候变化的影响和适应结论有多大影响？特别是，该项目将在四个河流系统上实施22个水文模型，以评估选择潜在蒸散公式的影响和确定相关水文模型参数的重要性。不适当的参数选择可能会导致模型的行为与其寻求模拟的自然系统不同，而气候变化可能会使潜在的蒸散公式超出其校准范围。这项拟议的研究将使用四项未来气候预测，目标是涵盖各种可能的未来温度和降雨量。评估和比较过程将不仅基于典型的水文评分和水平衡组件，它还将利用实际的大坝管理应用作为补充的评估手段。此外，将通过详细查看模型结构来分析模拟中的巨大差异。所有这些工作都旨在提高加拿大及时调整其水管理计划的能力。