Model Studies of Surface Water Behavior on Ice Shelves

MacAyeal/0944248该奖项支持一个项目，以更好地了解触发冰架不稳定和爆炸解体的过程和条件。拟议研究的一个重要成果将是建立预测未来海平面上升的大尺度冰盖模型所需的微尺度和中尺度冰架表面过程的参数化。 拟议的研究是一项为期3年的努力，对南极冰架表面水演变的6个方面进行数值模型研究。这6个模型研究领域包括融化冰架表面的能量平衡模型，处理表面池塘和充水裂缝，分布式，Darcian水流模拟模拟初始积雪融化，盐水渗透，池塘排水和裂缝填充，冰架表面地形演变的相变模拟（表面融化和冻结）、表面径流驱动的侵蚀和渗流、冰架和冰山表面的质量负荷和挠曲效应;表面水负荷和挠曲应力之间的反馈;表面水、冰和底层海洋可能出现的假潮现象，这些现象构成了引起表面裂缝的机制。表面池塘和决口对流，以及基底决口热盐对流（与上述区域5有关的现象）。 拟议工作的更广泛影响涉及气候变化和海平面上升的社会环境问题，并将有助于实现为公共政策提供咨询意见的重要目标。该项目将构成研究生论文项目的基础，其培训将有助于国家的科学劳动力，PI和研究生将另外参加由芝加哥大学同事组织的高中教师暑期科学丰富计划。

MacAyeal/0944248This award supports a project to develop a better understanding of the processes and conditions that trigger ice shelf instability and explosive disintegration. A significant product of the proposed research will be the establishment of parameterizations of micro- and meso-scale ice-shelf surface processes needed in large scale ice-sheet models designed to predict future sea level rise. The proposed research represents a 3-year effort to conduct numerical model studies of 6 aspects of surface-water evolution on Antarctic ice shelves. These 6 model-study areas include energy balance models of melting ice-shelf surfaces, with treatment of surface ponds and water-filled crevasses, distributed, Darcian water flow modeling to simulate initial firn melting, brine infiltration, pond drainage and crevasse filling, ice-shelf surface topography evolution modeling by phase change (surface melting and freezing), surface-runoff driven erosion and seepage flows, mass loading and flexure effects of ice-shelf and iceberg surfaces; feedbacks between surface-water loads and flexure stresses; possible seiche phenomena of the surface water, ice and underlying ocean that constitute a mechanism for, inducing surface crevassing., surface pond and crevasse convection, and basal crevasse thermohaline convection (as a phenomena related to area 5 above). The broader impacts of the proposed work bears on the socio-environmental concerns of climate change and sea-level rise, and will contribute to the important goal of advising public policy. The project will form the basis of a dissertation project of a graduate student whose training will contribute to the scientific workforce of the nation and the PI and graduate student will additionally participate in a summer science-enrichment program for high-school teachers organized by colleagues at the University of Chicago.