Collaborative Research: A new reconstruction of the last West Antarctic Ice Sheet deglaciation in the Ross Sea

合作研究：罗斯海最后一次西南极冰盖消融的新重建

• 批准号: 1043517
• 负责人: Peter Clark
• 金额: $ 19.85万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1043517&HistoricalAwards=false
• 关键词: Collaborative; Research; new; reconstruction; last

1043517/ClarkThis award supports a project to develop a better understanding of the response of the WAIS to climate change. The timing of the last deglaciation of the western Ross Sea will be improved using in situ terrestrial cosmogenic nuclides (3He, 10Be, 14C, 26Al, 36Cl) to date glacial erratics at key areas and elevations along the western Ross Sea coast. A state-of-the art ice sheet-shelf model will be used to identify mechanisms of deglaciation of the Ross Sea sector of WAIS. The model results and forcing will be compared with observations including the new cosmogenic data proposed here, with the aim of better determining and understanding the history and causes of WAIS deglaciation in the Ross Sea. There is considerable uncertainty, however, in the history of grounding line retreat from its last glacial maximum position, and virtually nothing is known about the timing of ice- surface lowering prior to ~10,000 years ago. Given these uncertainties, we are currently unable to assess one of the most important questions regarding the last deglaciation of the global ice sheets, namely as to whether the Ross Sea sector of WAIS contributed significantly to meltwater pulse 1A (MWP-1A), an extraordinarily rapid (~500-year duration) episode of ~20 m sea-level rise that occurred ~14,500 years ago. The intellectual merit of this project is that recent observations of startling changes at the margins of the Greenland and Antarctic ice sheets indicate that dynamic responses to warming may play a much greater role in the future mass balance of ice sheets than considered in current numerical projections of sea level rise. The broader impacts of this work are that it has direct societal relevance to developing an improved understanding of the response of the West Antarctic ice sheet to current and possible future environmental changes including the sea-level response to glacier and ice sheet melting due to global warming. The PI will communicate results from this project to a variety of audiences through the publication of peer-reviewed papers and by giving talks to public audiences. Finally the project will support a graduate student and undergraduate students in all phases of field-work, laboratory work and data interpretation.

1043517/Clark 该奖项支持一个项目，旨在更好地了解 WAIS 对气候变化的响应。将利用原位陆地宇宙成因核素（3He、10Be、14C、26Al、36Cl）来确定罗斯海西海岸关键区域和高地的冰川不稳定现象，从而改善西罗斯海最后一次冰消期的时间。 最先进的冰盖-架模型将用于确定 WAIS 罗斯海区域的冰川消融机制。模型结果和强迫将与包括这里提出的新宇宙成因数据在内的观测结果进行比较，目的是更好地确定和理解罗斯海 WAIS 冰消的历史和原因。然而，接地线从最后一次冰期最大位置退缩的历史存在相当大的不确定性，而且对于约一万年前冰面下降的时间几乎一无所知。鉴于这些不确定性，我们目前无法评估有关全球冰盖上次消融的最重要问题之一，即 WAIS 的罗斯海区域是否对融水脉冲 1A (MWP-1A) 做出了重大贡献，这是一种异常的现象。约 14,500 年前发生的约 20 m 海平面快速上升（约 500 年持续时间）。该项目的智力价值在于，最近对格陵兰岛和南极冰盖边缘惊人变化的观察表明，对变暖的动态响应可能在未来冰盖的质量平衡中发挥比当前数值预测中考虑的更大的作用。海平面上升。这项工作更广泛的影响在于，它对于更好地了解西南极冰盖对当前和未来可能的环境变化的反应具有直接的社会意义，包括海平面对全球变暖导致的冰川和冰盖融化的反应。 PI 将通过发表同行评审论文以及向公众发表演讲，向各种受众传达该项目的结果。 最后，该项目将为研究生和本科生的实地工作、实验室工作和数据解释的各个阶段提供支持。