Collaborative Research:Grounding-line Retreat in the Southern Ross Sea - Constraints from Scott Glacier

合作研究：南罗斯海接地线后退——斯科特冰川的限制

• 批准号: 0636818
• 负责人: John Stone
• 金额: $ 38.88万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0636818&HistoricalAwards=false
• 关键词: Collaborative; Research; Grounding; line; Retreat

Hall/0636687This award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, surface velocity and surface mass balance will be measured to constrain an ice-flow model of the glacier. This model will be used to help interpret the dated geologic sequences. The intellectual merit of the project relates to gaining a better understanding of the West Antarctic Ice Sheet and how changing activity of fast-flowing outlet glaciers and ice streams exerts strong control on the mass balance of the ice sheet. Previous work suggests that grounding-line retreat in the Ross Sea continued into the late Holocene and left open the possibility of ongoing deglaciation as part of a long-term trend. Results from Reedy Glacier, an outlet glacier just behind the grounding line, suggest that retreat may have slowed substantially over the past 2000 years and perhaps even stopped. By coupling the work on Scott Glacier with recent data from Reedy Glacier, the grounding-line position will be bracketed and it should be possible to establish whether the retreat has truly ended or if it is ongoing. The broader impacts of the work relate to the societal relevance of an improved understanding of the West Antarctic ice sheet to establish how it will respond to current and possible future environmental changes. The work addresses this key goal of the West Antarctic Ice Sheet Initiative, as well as the International Polar Year focus on ice sheet history and dynamics. The work will develop future scientists through the education and training of one undergraduate and two Ph.D. students, interaction with K-12 students through classroom visits, web-based 'expedition' journals, letters from the field, and discussions with teachers. Results from this project will be posted with previous exposure dating results from Antarctica, on the University of Washington Cosmogenic Nuclide Lab website, which also provides information about chemical procedures and calculation methods to other scientists working with cosmogenic nuclides.

Hall/0636687 Try Award支持一个项目，该项目旨在调查Scott Glacier的晚更新世和全新世变化，Scott Glacier是一个主要的出口冰川，该项目直接流入当今西南极冰盖（WAIS）接地线以西的Ross Sea。总体目标是了解上次冰川最大（LGM）以来罗斯海部门中的WAIS配置的变化，并确定在Ross胚胎中观察到的全新世撤退是否已经结束或仍在进行中。为了解决这些目标，将绘制与Scott冰川相关的冰or和漂移序列，并将其绘制日期，并测量冰厚度，表面速度和表面质量平衡，以限制冰川的冰流模型。该模型将用于帮助解释过时的地质序列。该项目的智力优点涉及更好地了解南极西南冰盖，以及快速流动出口冰川和冰流的活动如何对冰盖的质量平衡产生强大的控制。 先前的工作表明，罗斯海的基线撤退继续进入全新后期，并打开了作为长期趋势的一部分持续退化的可能性。 Reedy Glacier（在接地线后面的出口冰川）的结果表明，在过去的2000年中，撤退可能已经大大放缓，甚至可能停止了。 通过将Scott Glacier上的工作与Reedy Glacier的最新数据相结合，接地线的位置将被包围，应该可以确定务虚会是否真正结束或正在进行。这项工作的更广泛影响与对西南极冰盖的改进理解的社会相关性有关，以确定它将如何应对当前和可能的未来环境变化。这项工作旨在解决西南极冰盖计划的这一关键目标，以及国际极性年的重点是冰盖历史和动态。这项工作将通过对一个本科和两位博士学位的教育和培训来发展未来的科学家。学生，通过课堂访问与K-12学生的互动，基于网络的“探险”期刊，现场来信以及与老师的讨论。该项目的结果将在华盛顿大学宇宙核素实验室网站上的先前的暴露约会结果发布，该网站还提供了有关化学程序和计算方法的信息，并向使用宇宙核素工作的其他科学家提供了信息。