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

利用SAR干涉测量、冰架热机械模型和海洋潮汐模型分析南极冰架裂谷、崩解和冰前海洋相互作用

基本信息

批准号：
9818622
负责人：
Douglas MacAyeal
金额：
$ 17.28万
依托单位：
University of Chicago
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
1998
资助国家：
美国
起止时间：
1998-10-01 至 2002-09-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=9818622&HistoricalAwards=false
关键词：
Analysis Antarctic Ice Shelf Rifting

项目摘要

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.

该奖项旨在支持利用合成孔径雷达（SAR）干涉测量、冰架热机械模型和海洋潮汐模型对南极冰架裂谷、崩解和冰锋海洋相互作用进行研究。南极冰盖的质量平衡在很大程度上是由围绕冰盖向海周边的大型冰架崩解的冰山所控制的。这项工作旨在加深对冰架流动和裂谷过程的了解。拉森冰架最北端最近的破裂表明，由于环境变化，冰架可能会通过涉及预先存在的分离裂缝的“分解”过程而灾难性地解体。这项工作将解决较大的菲尔希纳-龙冰架和罗斯冰架是否可能发生类似分裂的问题。裂谷的存在被认为是冰架突然破裂的必要条件，融水形成和表面积水等过程被认为是导致裂谷分离的额外充分（有利）条件。这项研究的重点是控制潮汐和蠕变流过程，通过这些过程产生裂谷。这项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建模以及冰架蠕变流的有限元热机械建模。将研究控制冰架破裂、崩解、流动以及与海洋和大气相互作用的过程。