Collaborative Research: Anisotropy, Abrupt Climate Change, and the Deep Ice in West Antarctica

该奖项支持一个项目，以限制积累率，厚度，和温度历史的Siple圆顶使用垂直速度剖面，其中包括随着时间的推移变形不断变化的结构的影响，反演的深度剖面的结构确定从声速测量和晶粒尺寸观察薄部分在Siple圆顶的表面温度和积累率的变化在过去，重点研究了22ka和15ka的明显气候突变事件。这项工作的智力价值是，它将利用一个耦合的结构演变和冰盖流动模型，从深冰的一些物理特性中提取过去的气候信息。重点将放在Siple Dome的深层冰河时期的冰上，那里的冰芯记录显示出令人困惑的信号，模拟结果暗示了有趣的变形模式。该方法还将应用于伯德站和泰勒穹的记录，最终形成未来分析西南极分水岭岩心的基础。该项目更广泛的影响是，它将最终有助于我们了解各向异性对南极洲西部冰流动力学的影响。 这将有助于我们理解冰流和冰芯中的古气候记录之间的联系，特别是在化学记录和冰变形之间的关系。这将有助于一个新的冰流模型，包括各向异性和结构演变的影响。 该项目还将促进一名新的年轻女性调查员的职业发展，并将支持几名研究生。 最后，这项工作将通过直接帮助支持冰上女孩项目来鼓励物理科学的多样性，该项目鼓励年轻女性探索科学和自然世界。

This award supports a project to constrain the accumulation rate, thickness, and temperature history for Siple Dome using a vertical velocity profile that includes the effects of an evolving fabric on deformation through time, to invert the depth-profile of fabric determined from sonic velocity measurements and grain size observed in thin sections in Siple Dome for the surface temperature and accumulation rate changes in the past, focusing on the apparent abrupt climate change events at 22ka and 15ka. The intellectual merit of the work is that it will extract past climate information from a number of physical properties of the deep ice using a coupled fabric evolution and ice-sheet flow model. The focus will be on the deep ice-age ice at Siple Dome, where the ice-core record shows puzzling signals and where modeling results imply intriguing deformation patterns. The method will also be applied to the records from Byrd Station and Taylor Dome to ultimately form a basis for future analysis of the West Antarctic Divide core. The broader impacts of the project are that it will ultimately contribute to our understanding of the effects of anisotropy on ice flow dynamics in West Antarctica. It will contribute to our understanding of the connection between ice flow and the paleoclimate record in ice cores, particularly with respect to the relationship between the chemical record and ice deformation. And it will contribute a new ice-flow model that includes the effects of anisotropy and fabric evolution. The project will also contribute to advancing the career of a new, young, female investigator and will support a couple of graduate students. Finally, the work will encouraging diversity in the physical sciences by directly helping to support the Girls on Ice a program that encourages young women to explore science and the natural world.