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: 1043485
• 负责人: Joshua Curtice
• 金额: $ 18.4万
• 依托单位: Woods Hole Oceanographic Institution
• 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 2015-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1043485&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，该项目旨在更好地了解世界气候变化研究所对气候变化的反应。罗斯海西部最后一次冰川消融的时间将利用原位陆地宇宙成因核素(3He、10Be、14C、26Al、36Cl)来确定罗斯海西部海岸关键地区和海拔的冰川变化率。一个最先进的冰盖-陆架模型将被用来确定WAIS罗斯海部分的冰川消融机制。为了更好地确定和理解罗斯海WAIS冰川消退的历史和原因，模型结果和强迫将与观测结果进行比较，包括这里提出的新的宇宙成因数据。然而，在接地线从最后一次冰川最大位置撤退的历史上，存在着相当大的不确定性，而且在大约10,000年前，人们几乎对冰面下降的时间一无所知。鉴于这些不确定性，我们目前无法评估有关全球冰盖最后一次消融的最重要问题之一，即WAIS的罗斯海部分是否对融水脉冲1A(MWP-1A)做出了重大贡献，MWP-1A是大约14,500年前发生的约20米海平面上升的极快(约500年)事件。该项目的学术价值在于，最近对格陵兰和南极冰盖边缘惊人变化的观察表明，对气候变暖的动态反应可能会在未来冰盖的质量平衡中发挥比目前海平面上升数字预测所考虑的更大的作用。这项工作的更广泛影响是，它具有直接的社会意义，有助于更好地了解南极西部冰盖对当前和未来可能发生的环境变化的反应，包括海平面对全球变暖导致的冰川和冰盖融化的反应。国际和平协会将通过发表同行评议的论文和向公众发表演讲，将这一项目的结果传达给各种受众。最后，该项目将在实地工作、实验室工作和数据解释的所有阶段支持一名研究生和本科生。