The Relationship between Climate and Ice Rheology at Dome C, East Antarctica

东南极洲 Dome C 气候与冰流变学的关系

• 批准号: 0948247
• 负责人: Erin C Pettit
• 金额: $ 45.92万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0948247&HistoricalAwards=false
• 关键词: Relationship; between; Climate; Ice; Rheology

Pettit/0948247This award supports a project to study of the relationship between fabric and climate for the ice near the EPICA Dome C ice core site, East Antarctica. The work builds on an ongoing study at Siple Dome, West Antarctica and takes advantage of collaborations with European scientists and access to the Dome C borehole to make measurements of sonic velocity. The intellectual merit of the project is that a better understanding of how fabric preserves past climate information can improve models of the ice flow near ice core sites and the interpreta-tion of ice core data (particularly paleo-accumulation), and it may allow us to extract climate information directly from fabric data. In addition, because ice deformation is sensitive to the orientation of crystals, ice flow patterns are sensitive to the fabric. Thus, variations in the fabric between glacial and interglacial ice can affect how ice deforms and how fabric in the ice sheet develops. The Dome C site is particularly important for answering these questions, because the ice core shows evidence of eight glacial cycles, not just one as found at Siple Dome or the Greenland sites. The research will improve the understanding of the proxy relationship between sonic-velocity data and fabric; will help to model the pattern of ice flow caused by the fabric variation between glacial and interglacial time periods using these data, existing ice core chemistry and existing and new thin section data, improved surface strain data, and borehole deformation data; and will help to better understand the positive feedback mechanism that enhances fabric (and corresponding rheological) variability through a focused study of several climate transitions and the associated fabric changes. Borehole compressional-wave sonic-velocity will be measured which will complement the sonic-velocity data that already exist for boreholes in Greenland and West Antarctica. These will be the first sonic-velocity measurements in East Antarctica and the first measurements that extend for more than a single glacial/interglacial transition. The project will ultimately contribute to better interpretation of ice core records for both paleoclimate studies and for ice flow history, both of which connect to the broader questions of the role of ice in the climate system. This project will also strengthen the international collaborations within the paleoclimate and ice sheet modeling communities. This project will partially support a graduate student at the University of Alaska Fairbanks who is currently working on modeling ice including anisotropy and it will support the growth of a young scientist through a Post-Doc position. This Post Doc will gain important experience collaborating with the EPICA scientists in studying the climate-fabric relationship. Erin Pettit is active in field-science education for high school students, under-graduates, teachers, and adults. This project will help support the continued development and enhancement of Girls on Ice a program that encourages young women to explore science and the natural world.

PETTIT/0948247这奖支持一个研究一个项目，以研究Epica Dome C Ice Core Core Site附近的冰块之间的关系和气候之间的关系。这项工作是基于西南极西部Siple Dome正在进行的一项研究，并利用与欧洲科学家的合作，并进入圆顶C钻孔以进行声音速度的测量。 该项目的智力优点在于，更好地了解织物如何保留过去的气候信息可以改善冰核站点附近的冰流的模型和冰核数据的解释（尤其是古蓄能），并且它可以使我们可以直接从面料数据中提取气候信息。 另外，由于冰变形对晶体的方向敏感，因此冰流图案对织物敏感。因此，冰川和冰川间冰之间的织物的变化会影响冰形变形以及冰盖中的织物的发展方式。 圆顶C网站对于回答这些问题尤其重要，因为冰核显示了八个冰川周期的证据，而不仅仅是在Siple Dome或Greenland遗址所示的证据。 这项研究将提高对声音速度数据和织物之间代理关系的理解。将有助于模拟使用这些数据，现有的冰核化学以及现有和新的薄截面数据，改进的表面应变数据以及井眼变形数据的冰川和冰间时间之间的织物变化引起的冰流模式；并将通过对几种气候过渡和相关织物变化的重点研究的重点研究来更好地理解积极的反馈机制，从而增强了织物（并相应的流变）变异性。 将测量钻孔压缩波声速度，这将补充格陵兰岛和西南极洲西部井眼已经存在的声音速度数据。 这些将是东南极洲东部的第一个声速测量值，也是第一个延伸超过单个冰川/冰川间过渡的测量值。 该项目最终将有助于更好地解释古气候研究和冰流历史的冰核记录，这两者都将冰块在气候系统中的作用更为广泛。该项目还将加强古气候和冰盖建模社区内的国际合作。该项目将部分支持阿拉斯加费尔班克斯大学的研究生，该大学目前正在努力建模包括各向异性在内的冰，并将通过DOSED职位来支持年轻科学家的成长。这篇文章将获得与Epica科学家合作研究气候模仿关系的重要经验。艾琳·佩蒂特（Erin Pettit）活跃于高中生，大学生，老师和成人的现场科学教育。该项目将有助于支持冰上女孩的持续发展和增强计划，该计划鼓励年轻女性探索科学和自然世界。