Collaborative Research: Glacier-Ocean Coupling in a Large East Greenland Fjord

合作研究：东格陵兰峡湾的冰川-海洋耦合

• 批准号: 0909282
• 负责人: Leigh Stearns
• 金额: $ 16.45万
• 依托单位: University of Kansas Center for Research Inc
• 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: 2009-08-15 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0909282&HistoricalAwards=false
• 关键词: Collaborative; Research; Glacier; Ocean; Coupling

This award will support a study of glacier-fjord interactions in east Greenland. The 'Intellectual Merit' of the proposed study lies in the current understanding that the contribution of the Greenland Ice Sheet to sea level rise more than doubled in the last seven years, mostly because of a widespread and nearly simultaneous acceleration of many glaciers that terminate at tidewater in deep fjords. Understanding the causes of changes in glacier dynamics, and predicting their future trajectories is a topic of enormous scientific and societal importance. The Greenland fjords provide an intimate connection between the ice sheet and the ocean and, in turn, raise the possibility that the observed warming of the ocean around southeast and western Greenland was the trigger for recent changes in outlet glacier dynamics. A pilot study conducted by the PIs in east Greenland, and a separate study in west Greenland, found warm ocean waters in the proximity of Helheim Glacier and Jakobshavn Isbræ, respectively, supporting the hypothesis that their acceleration was triggered by ocean warming. While intriguing, the presence of warm waters in Greenland's fjords alone is not enough to conclude that the ocean is modulating glacier dynamics. A test of this hypothesis requires a more detailed understanding of glacier/fjord interactions than is possible with the limited amount of data currently available. This study will fill this gap by investigating glacier-ocean interactions in a typical glacier-fjord system in East Greenland (Sermilik Fjord and Helheim Glacier) through an intensive two-year field program. Through summer surveys and year-round moored instruments, the circulation and properties of the fjord on tidal to yearly time-scales will be mapped, and the liquid fresh water flux out of the fjord will be quantified. A collaboration with Greenlandic marine biologists will allow important ocean data in the region outside the fjord to be obtained using tagged seals. GPS methods and remote sensing will allow changes in the flow behavior of Helheim Glacier to be examined in the context of changing fjord circulation. Satellite remote sensing and field tracking of large icebergs will provide estimates of the solid export of fresh water and its variability. The proposed study has numerous 'Broader Impacts'. The are likely to be a significant component of next-generation ice sheet models seeking to predict the evolution of the Greenland Ice Sheet and future rates of sea level rise. The project brings together an inter-disciplinary group of investigators, involves two junior scientists embarking on their careers, and initiates an international collaboration with Greenlandic scientists. A graduate student will be trained in glaciology and physical oceanography, contributing to society's need for experts in the area of ice sheet-ocean interactions. The fieldwork utilizes local vessels and relies strongly on the knowledge of generations of local hunters who have navigated Sermilik Fjord, thus fostering a two-way exchange between the local community and foreign scientists. A non-technical report summarizing the findings of ocean-glacier measurements will distributed in the local community, which is vulnerable to rapid environmental changes affecting its primary natural resource.

该奖项将支持对东格陵兰岛冰川峡湾互动的研究。拟议的研究的“智力优点”在于当前的理解是，格陵兰冰盖对海平面的贡献在过去七年中的贡献增加了一倍以上，这主要是因为许多冰川在深层峡湾中终止的许多冰川终止了许多冰川。了解冰川动态变化的原因，并预测其未来的轨迹是一个巨大的科学和社会重要性的话题。格陵兰峡湾提供了冰盖和海洋之间的紧密联系，进而提高了观察到的东南和西部格陵兰岛海洋变暖的可能性，这是最近发生冰川动力学变化的触发因素。 PIS在东格陵兰进行的一项试点研究，在西格陵兰进行了另一项研究，分别在Helheim Glacier和JakobshavnIsbræ的附近发现了温暖的海水，支持了这样的假设，即它们的加速度是由海洋变暖触发的。虽然有趣，但仅格陵兰峡湾中的温暖水域就不足以包含海洋调节冰川动力学。对该假设的检验需要比当前可用的数据有限的数据对冰川/峡湾相互作用有更详细的了解。这项研究将通过在东格陵兰岛（Sermilik Fjord和Helheim Glacier）的典型冰川峡湾系统中调查冰川 - 海洋相互作用来填补这一空白。通过夏季调查和全年的停泊仪器，将绘制峡湾对潮汐对年度尺度的循环和特性，并将量化峡湾的液态淡水通量。与格陵兰海洋生物学家的合作将允许使用标记密封件获得峡湾以外地区的重要海洋数据。 GPS方法和遥远灵敏度将使Helheim冰川的流动行为发生变化，以在改变峡湾循环的背景下进行检查。大型冰山的卫星遥感和现场跟踪将估计淡水的固体出口及其可变性。拟议的研究具有许多“更广泛的影响”。这些可能是下一代冰盖模型的重要组成部分，以预测格陵兰冰盖的演变和未来的海平面上升速度。该项目汇集了一个跨学科的研究人员，涉及两名初级科学家开始自己的职业生涯，并与格陵兰科学家进行了国际合作。一名研究生将接受冰川学和物理海洋学的培训，这有助于社会对冰原互动领域的专家的需求。现场工作利用当地船只，并强烈依赖于有导航Sermilik Fjord的当地猎人的知识，从而促进了当地社区与外国科学家之间的双向交流。一份非技术性报告总结了海洋冰川测量结果的一项非技术性报告，将在当地社区中分布，这容易受到影响其主要自然资源的快速环境变化。