Analysis of Antarctic Ice-Shelf Rifting, Calving and Ice-Front Ocean Interaction Using SAR Interferometry, Ice-Shelf Thermomechanical Models and Ocean Tidel Models

该奖项旨在支持一项利用合成孔径雷达（SAR）干涉测量、冰架热力学模型和海洋潮汐模型研究南极冰架裂谷、崩解和冰锋海洋相互作用的研究。南极冰原的物质平衡在很大程度上是由冰原向海边缘的大型冰架上的冰山崩解所控制的。这项工作旨在发展对冰架流动和裂谷过程的理解。拉森冰架最北端最近的破裂表明，冰架可能会因环境变化而发生灾难性的解体，这是一种涉及先前存在的分离裂缝的“解体”过程。这项工作将解决一个问题，即更大的费尔奇纳-罗恩冰架和罗斯冰架是否可能发生类似的破裂。裂谷的存在被认为是冰架突然破裂的必要条件，而融水的形成和地表积水等过程被认为是导致裂谷分离的额外充分（有利）条件。这项研究的重点将放在控制潮汐和爬行-流动的过程中，由这些过程产生裂缝。本研究将涉及合成孔径雷达（SAR）干涉测量，海洋潮汐的有限差分模拟，以及冰架蠕变流的有限元热力学模拟。控制冰架断裂、崩解、流动以及与海洋和大气相互作用的过程将被调查。

This award is to support a study of Antarctic ice-shelf rifting, calving, and ice-front ocean interaction using synthetic aperture radar (SAR) interferometry, ice-shelf thermomechanical models and ocean tidal models. The mass balance of the Antarctic ice sheet is governed in large part by iceberg calving from the large-scale ice shelves which surround the ice sheet's seaward perimeter. This work is designed to develop an understanding of ice-shelf flow and rifting processes. The recent break-up of the northernmost portion of the Larsen Ice Shelf suggests that ice shelves can catastrophically disintegrate in response to environmental change by a "disaggregation" process involving pre-existing detachment rifts. This work will address the question of whether similar break-up could be possible for the larger Filchner-Ronne and Ross ice shelves. The existence of rifts is believed to be a necessary condition for sudden ice-shelf break-up, and processes such as meltwater formation and surface ponding are believed to be the additional sufficient (enabling) condition that causes rifts to separate. The focus of this study will be on the governing tidal and creep-flow processes by which rifts are created. This study will involve synthetic aperture radar (SAR) interferometry, finite difference modeling of ocean tides, and finite-element thermomechanical modeling of ice-shelf creep flow. The processes that govern ice-shelf fracture, calving, flow and interaction with the ocean and atmosphere will be investigated.