Collaborative Research: Greenland Ice Sheet Basal Hydrology and Sliding Dynamics ? The Proof of the Drill

合作研究：格陵兰冰盖基础水文学和滑动动力学？

• 批准号: 0909495
• 负责人: Joel Harper
• 金额: $ 47.43万
• 依托单位: University of Montana
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0909495&HistoricalAwards=false
• 关键词: Collaborative; Research; Greenland; Ice; Sheet

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Recent changes in the flow dynamics and overall geometry of the Greenland Ice Sheet have been concurrent with increased surface melting: the velocity of some outlet glaciers has increased, the ice sheet margins have thinned, and the overall mass of the ice sheet has declined by more than melt alone can account for. A direct linkage between surface melt and ice sheet change is commonly argued but has not been proven. In the proposed work, direct connections between surface melt, the basal hydrological system, and ice motion will be quantified along a flow-line transect of the Greenland Ice Sheet. The region to be studied receives high surface melt, but is located far from the influence of ocean tidewater dynamics. Basal conditions will be directly measured in six boreholes drilled to the bed, with two holes at each of three sites. Surface melt and spatial gradients in ice velocity will be quantified to enable detailed comparison between melt water forcing, basal hydrologic conditions, and ice flow dynamics. Instrumentation at the surface, within the ice, and at the bed will collect data at high time resolution for up to 2 years. Two models will be used to interpret the mechanical and thermal context of the measurements. In turn, the intensive measurement campaign will uniquely constrain the modeling and enable model assessment. This integrated measurement and modeling campaign will be a comprehensive investigation of the role of water in ice sheet motion. This work will support two Ph.D. dissertations and provide field research experiences to at least five students. Several informal education and outreach activities will be supported, including a high proportion of Native American participants.

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。格陵兰冰盖的流动动力学和整体几何形状的最近变化与表面融化的增加同时发生：一些出口冰川的速度增加，冰盖边缘变薄，冰盖的整体质量下降超过融化本身。表面融化和冰盖变化之间的直接联系通常被认为是有争议的，但尚未得到证实。在拟议的工作中，表面融化，基础水文系统和冰运动之间的直接联系将被量化沿着格陵兰冰盖的流线断面。所研究的区域接受高表面熔体，但远离海洋潮汐动力学的影响。基础条件将直接测量六个钻孔钻到床上，两个孔在三个网站。冰速度的表面融化和空间梯度将被量化，使融水强迫，基础水文条件和冰流动力学之间的详细比较。在表面、冰内和冰床上的仪器将以高时间分辨率收集数据，时间长达2年。将使用两个模型来解释测量的机械和热环境。反过来，密集的测量活动将唯一地约束建模并使模型评估成为可能。这一综合测量和建模活动将是对水在冰盖运动中的作用的全面调查。这项工作将支持两个博士学位。论文，并提供实地研究经验，至少五名学生。将支助几项非正式教育和外联活动，包括很大比例的美洲土著人参与。