Better boundary conditions for glacier and ice-sheet modelling

更好的冰川和冰盖建模边界条件

• 批准号: RGPIN-2015-05722
• 负责人: Flowers, Gwenn
• 金额: $ 2.99万
• 依托单位: Simon Fraser University
• 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=688205
• 关键词: Better; boundary; conditions; glacier; ice

Glaciers and ice sheets store two-thirds of Earth's freshwater and are currently contributing to rising sea levels. While these ice masses act as long-term integrators of climate, their internal dynamics can complicate their behaviour on the short timescales relevant to society. Fundamental to our ability to decipher the underlying causes of glacier and ice-sheet change, and therefore pre-requisite to its reliable future projection, are accurate "boundary conditions" for glacier and ice-sheet models. The motivation for the proposed research is therefore to inform models we use to make projections of glacier change through process-based studies at the glacier surface and bed, and where the glacier comes into contact with freshwater reservoirs. The specific objectives of the research program are to (1) evaluate the robustness of glacier mass-balance models to uncertainties in accumulation processes, (2) develop statistical models of subglacial processes at scales commensurate with ice-sheet models and (3) investigate the influence of glacier-freshwater interactions on glacier dynamics and retreat. A fourth cross-cutting objective is to develop statistically robust practices for model calibration and to quantify associated model uncertainties. Observational, computational and statistical methods will be combined to achieve the above objectives in a number of individual studies suitable for graduate-level research. These studies involve new field work in British Columbia and Yukon to measure meteorological quantities, glacier mass balance, subglacial variables and properties of ice-marginal lakes. This research program capitalizes on emergent collaborations with local and international colleagues, as well as a new collaboration based at SFU between statisticians and earth scientists. It also involves partnership with local industry to develop novel instrumentation for monitoring subglacial properties. Built into the program are training opportunities for 6 new graduate students, along with 2 undergraduates and 1 northern community member per year. The anticipated impact of the research program will be an improved ability to (1) accurately model regional glacier mass-balance, (2) implement realistic representations of subglacial processes in large-scale ice-sheet models and (3) include glacier-freshwater feedbacks in future assessments of glacier change. Collectively, the proposed research will advance our understanding of externally driven- versus internally forced glacier change, toward more confident interpretations of short-term glacier variations and improved future projections. These projections are broadly relevant to issues of Canada's water security, economic development and environmental resilience.*** **

冰川和冰盖储存着地球三分之二的淡水，目前正在导致海平面上升。虽然这些冰块是气候的长期整合者，但它们的内部动态可能会使它们在短期内的行为变得复杂化，这对社会至关重要。我们破译冰川和冰盖变化的根本原因的能力，因此是其可靠的未来预测的先决条件，是冰川和冰盖模型的准确“边界条件”的动机。因此，拟议的研究旨在为我们使用的模型提供信息，通过对冰川表面和河床以及冰川与淡水水库接触的位置进行基于过程的研究来预测冰川变化。该研究计划的具体目标是（1）。 ）评估冰川质量平衡模型对积累过程不确定性的稳健性，（2）开发与冰盖模型相匹配的冰下过程统计模型，（3）研究冰川-淡水相互作用的影响第四个跨领域目标是开发专业稳健的模型校准实践，并量化相关模型的不确定性，将结合观测、计算和统计方法，在许多适合的单独研究中实现上述目标。这些研究涉及不列颠哥伦比亚省和育空地区的新实地工作，以测量气象量、冰川质量平衡、冰下变量和冰缘湖泊的特性，该研究项目利用了与当地和国际同事的紧急合作。该项目还包括统计学家和地球科学家在 SFU 的一项新合作，以开发用于监测冰下特性的新型仪器，并为 6 名新研究生、2 名本科生和 1 名北方学生提供培训机会。该研究计划的预期影响将是提高以下能力：（1）准确模拟区域冰川质量平衡，（2）在大型冰盖模型中实现冰下过程的真实表示，以及（3）包括总的来说，拟议的研究将增进我们对外部驱动冰川变化与内部强迫冰川变化的理解，从而对短期冰川变化做出更自信的解释并改进未来预测。加拿大的水安全、经济发展和环境恢复力问题。*** **