International Research Fellowship Program: Inferring Changes in Ice-Sheet Flow and Accumulation

国际研究奖学金计划：推断冰盖流动和积累的变化

• 批准号: 0853407
• 负责人: Michelle Koutnik
• 金额: $ 14.07万
• 依托单位: Koutnik Michelle R
• 依托单位国家: 美国
• 项目类别: Fellowship
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2012-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0853407&HistoricalAwards=false
• 关键词: International; Research; Fellowship; Program; Inferring

0853407KoutnikThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.This award will support a twenty-four-month research fellowship by Dr. Michelle R. Koutnik to work with Dr. Dorthe Dahl-Jensen at the University of Copenhagen?s Centre for Ice and Climate Studies in Denmark.The spatial and temporal histories of ice-sheet flow and accumulation are necessary to recreate past ice-volume and sea-level histories, and to predict the response of ice sheets to future climate changes. Some details of these valuable histories can be recovered from ice cores, but ice cores represent conditions at only a single point. Since it is resource intensive to recover a deep ice core, it is impractical to reconstruct the important spatial dimension from ice cores alone. A solution is to use available ice-penetrating radar data to infer this information.Ice-penetrating-radar profiles are windows to the interior of glaciers and ice sheets. These views inside the ice show internal layers that have been shaped by spatial and temporal changes in ice flow, in ice thickness, and in accumulation. The deepest visible layers have been significantly affected by spatial and temporal gradients in ice flow and accumulation. Therefore, deep layers are highly valuable, but they are also more complicated to interpret. The PI uses an inverse-theory approach to properly extract this valuable information. Radar-imaged internal layers may be the only accessible surviving archive that contains a record of past spatial and temporal variations in ice flow and accumulation over broad areas of the ice sheets and ice caps, and reaching far into the past. In collaboration with host scientist, Dr. Dorthe Dahl-Jensen, and the team of researchers at the Center for Ice and Climate Studies at the University of Copenhagen, the PI is addressing important questions about the relationship between climate changes and ice-sheet evolution for parts of the Greenland Ice Sheet and Arctic Ice Caps.

0853407Koutnik 该奖项根据 2009 年美国复苏和再投资法案（公法 111-5）提供资金。国际研究奖学金计划使美国科学家和工程师能够在国外进行九到二十四个月的研究。 该项目的奖项为联合研究以及使用国外独特或互补的设施、专业知识和实验条件提供了机会。该奖项将支持 Michelle R. Koutnik 博士与丹麦哥本哈根大学冰与气候研究中心的 Dorthe Dahl-Jensen 博士合作为期 24 个月的研究奖学金。冰盖流动和积累的空间和时间历史对于重建冰盖流动和积累的空间和时间历史是必要的。 过去的冰量和海平面历史，并预测冰盖对未来气候变化的反应。这些有价值的历史的一些细节可以从冰芯中恢复，但冰芯仅代表单个点的条件。 由于恢复深层冰芯需要大量资源，因此仅从冰芯重建重要的空间维度是不切实际的。 解决方案是使用可用的破冰雷达数据来推断此信息。破冰雷达剖面是了解冰川和冰原内部的窗口。 这些冰内部的视图显示了由冰流、冰厚度和积累的空间和时间变化塑造的内部层。 最深的可见层受到冰流和积累的空间和时间梯度的显着影响。 因此，深层非常有价值，但解释起来也更复杂。 PI 使用逆向理论方法来正确提取这些有价值的信息。 雷达成像的内层可能是唯一可访问的幸存档案，其中包含过去冰流和冰盖和冰盖大面积积聚的空间和时间变化的记录，并且可以追溯到遥远的过去。 该项目负责人与东道科学家 Dorthe Dahl-Jensen 博士以及哥本哈根大学冰与气候研究中心的研究团队合作，正在解决有关格陵兰冰盖和北极冰盖部分地区气候变化与冰盖演化之间关系的重要问题。