Collaborative Research: Grounding Line Forensics: The History of Grounding Line Retreat in the Kamb Ice Stream Outlet Region

该合同支持一个项目，用于识别和绘制冰表面和内部特征，记录导致Kamb冰流关闭的事件序列。特别是，该项目将研究过去的接地线迁移以及该过程与冰流关闭之间的关系。该项目的知识价值包括这样一个事实，即对这些过程的理解对我们准确预测该地区物质平衡变化的能力具有重要意义。目前，南极西部五大冰流之一的坎布冰流处于静止状态，而另一条惠兰斯冰流的下游流速也在减慢。Kamb的停运似乎是从下游开始的，但除了简单的观察之外，还不可能对相邻的两条河流进行有意义的比较。我们不知道惠兰斯冰流上目前发生的事件是否与Kamb关闭期间发生的事件相似。这里提出的工作旨在弥合这一差距。预计这项工作将对接地线动力学对冰流的影响产生有用的见解。这项工作将结合使用无线电回波探测和GPS进行实地调查，并结合计算工作，包括解释冰表面特征，如残余流动痕迹和裂缝。该项目的更广泛影响将是解决具有重大社会影响的全球环境问题，培训下一代科学家和工程师为国家服务，并鼓励妇女从事科学或工程事业。两个机构的参与者都参与了一系列的公众宣传活动。

This award supports a project to identify and map ice surface and internal features that chronicle the sequence of events leading to the shut-down of Kamb ice stream. In particular, the project will study past grounding line migration and the relationship between that process and ice stream shutdown. The intellectual merits of the project include the fact that an understanding of such processes has important implications for our ability to accurately predict mass balance changes in this region. Currently, one of the five major West Antarctic ice streams, Kamb, is quiescent, and another, Whillans, is slowing in its downstream reaches. The Kamb shutdown appears to have begun at its downstream end but beyond that simple observation, it is not possible, yet, to draw meaningful comparisons between the two adjacent streams. We do not know if current events on Whillans Ice Stream are similar to what transpired during the Kamb shut-down. The work proposed here intends to bridge that gap. It is expected that this effort will yield useful insights into the influence of grounding line dynamics on ice stream flow. The work will involve a combination of field investigations using radio-echo sounding and GPS combined with computational efforts involving the interpretation of ice-surface features such as relict flow traces and crevasses. The broader impacts of the project will be in addressing a global environmental problem with critical societal implications, training the next generation of scientists and engineers to serve the nation, and encouraging women to pursue scientific or engineering careers. Participants from both institutions are involved in a range of public outreach activities.