A multi-scale analysis of subglacial hydrology and ice dynamics

冰下水文学和冰动力学的多尺度分析

• 批准号: RGPIN-2017-03761
• 负责人: Dow, Christine
• 金额: $ 3.35万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754884
• 关键词: multi; scale; analysis; subglacial; hydrology

The state of the subglacial environment is a first-order control on the flow of overlying ice. With greater volumes of water reaching the ice-bed interface in a warming world, basal hydrology development is a direct link between the impacts of climate change on ice dynamics and resulting sea-level rise. The difficulty of access to subglacial environments has hindered a detailed understanding of basal processes and vital questions remain about the role of water at the base of the Antarctic and Greenland ice sheets and in smaller but highly vulnerable valley glaciers. Use of numerical models is becoming increasingly beneficial for examining basal hydrology with the introduction of sophisticated 2D coupled models representing efficient and inefficient drainage. When this is combined with data inputs from satellite remote sensing, geophysical surveys and in situ data collection, it provides a powerful method for addressing areas where knowledge is currently lacking.This research program will utilize such methods on a variety of spatial and temporal scales ranging from conditions in Greenland and the Antarctic, to smaller scale processes at valley glaciers in the Yukon Territory and linking together the smaller and larger scale systems in the context of global climate. The research program objectives are in the short term (1-5 years) to 1) investigate the controls of subglacial hydrology on fast-flowing Antarctic ice streams, 2) examine ice-ocean interaction at Antarctic ice shelves and Greenland tidewater glaciers, 3) address the role of climate in glacier dynamics in the Yukon Territory and, in the longer term (3-10 years), utilize the outputs from objectives 1 through 3 to 4) incorporate basal processes and subglacial hydrology into large-scale ice sheet and global climate models. The outputs from these investigations into subglacial hydrology and ice dynamics over multiple spatial and temporal scales will give an unprecedented view of basal conditions of ice masses across the world. The combination of state-of-the-art models and data from multiple sources including remote sensing and in situ collection will provide a unique and detailed view of these vulnerable systems. The long-term goal to improve ice sheet models and global climate model predictions will utilize the results and experience gained from the individual research objectives and contribute to the next iterations of the Intergovernmental Panel on Climate Change (IPCC) report. In addition to this global approach, the individual projects will illuminate controls on ice dynamics for some of the regions most sensitive to climate-induced change, including the ablation area of the Greenland Ice Sheet, Antarctic ice streams, Antarctic ice shelves and valley glaciers that are currently diminishing the most rapidly due to warming temperatures.

冰下环境的状态是对上覆冰流的一级控制。在变暖的世界中，随着大量的水到达冰床界面，基础水文学的发展是气候变化对冰动态的影响与由此产生的海平面上升之间的直接联系。进入冰下环境的困难阻碍了对基础过程的详细了解，并且关于水在南极和格陵兰冰盖底部以及较小但高度脆弱的山谷冰川中的作用的重要问题仍然存在。随着代表高效和低效排水的复杂二维耦合模型的引入，数值模型的使用对于检查基础水文变得越来越有利。当这与卫星遥感、地球物理调查和现场数据收集的数据输入相结合时，它为解决目前缺乏知识的领域提供了一种强大的方法。该研究计划将在各种空间和时间尺度上利用这些方法从格陵兰岛和南极洲的条件，到育空地区山谷冰川的较小规模的过程，以及在全球气候背景下将较小和较大规模的系统连接在一起。该研究计划的目标是在短期（1-5年）内：1）研究冰下水文对快速流动的南极冰流的控制，2）研究南极冰架和格陵兰潮水冰川的冰-海洋相互作用，3）解决气候在育空地区冰川动态中的作用，并在较长时期内（3-10年）利用目标 1 至 3 至 4）的产出，纳入基础过程和冰下水文学到大规模冰盖和全球气候模型中。这些在多个时空尺度上对冰下水文学和冰动力学的研究的结果将为世界各地冰块的基础状况提供前所未有的视角。最先进的模型和来自多个来源（包括遥感和现场收集）的数据的结合将为这些脆弱系统提供独特而详细的视图。改进冰盖模型和全球气候模型预测的长期目标将利用从各个研究目标中获得的结果和经验，并为政府间气候变化专门委员会（IPCC）报告的下一次迭代做出贡献。除了这种全球方法之外，各个项目还将阐明对一些对气候引起的变化最敏感的地区的冰动态的控制，包括格陵兰冰盖的消融区域、南极冰流、南极冰架和山谷冰川，由于气温升高，目前减少速度最快。