Collaborative Research: Testing Arctic Ice Sheet Sensitivity to Abrupt Climate Change

合作研究：测试北极冰盖对气候突变的敏感性

• 批准号: 1417783
• 负责人: Jason Briner
• 金额: $ 15.73万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417783&HistoricalAwards=false
• 关键词: Collaborative; Research; Testing; Arctic; Ice

A team of investigators proposes to investigate the response of the Laurentide and Greenland Ice Sheets to two short term cooling events (several decades to a few centuries in duration) that occurred 9.3 and 8.2 thousand years ago. Assessing the sensitivity of ice sheets to short term climate variability is at the forefront of the scientific community's and the public's interest because short term ice sheet change will drive 21st century sea level rise. Thus a central question of the proposed work is whether ice sheets react abruptly to climate forcings, or are multi-millennial-scale trends in climate required to elicit a large-scale ice sheet response?The investigators propose an intensive field-based research program capitalizing on their newly published work reconstructing ice sheet change using high-precision beryllium-10 dating to test the hypothesis that prominent moraine systems marking former ice extents in West Greenland and Baffin Island record the synchronous advance of the Greenland and Laurentide ice sheets driven by the abrupt cooling events 9.3 and 8.2 thousand years ago. Pilot data reveal that portions of the ice sheet margin that are in contact with the surrounding ocean are able to respond rapidly to a short-lived climate perturbation. To test whether these documented changes were restricted to solely the most sensitive marine-terminating ice sheet sectors, or whether ice sheets are capable of a larger scale response to centennial-scale climate change, well-constrained chronologies of ice sheet change are needed from other regions. The investigators' research objectives are to 1) establish how land-terminating regions of ice sheets, which are more representative of broader ice sheet margins, respond to abrupt climate change, 2) further evaluate the role that oceanic forcing plays in modulating ice sheet response to short-lived climate perturbations, and 3) reconstruct the early Holocene behavior of mountain glacier systems (a proxy for summertime temperature) to evaluate what climatic conditions influenced the ice sheets. The investigators will work to make results easily accessible to the public. The work is led by an early career investigator and will support two graduate and several undergraduate students.

一组研究人员提议调查劳伦泰德冰盖和格陵兰冰盖对 9.3 年前和 8.2 千年前发生的两次短期变冷事件（持续几十年到几个世纪）的反应。评估冰盖对短期气候变化的敏感性是科学界和公众关注的首要问题，因为短期冰盖变化将推动 21 世纪海平面上升。因此，拟议工作的一个核心问题是冰盖是否会对气候强迫做出突然反应，或者是否需要数千年尺度的气候趋势才能引发大规模的冰盖响应？研究人员提出了一项密集的实地研究计划，该计划利用他们新发表的作品利用高精度铍 10 测年重建冰盖变化，以检验这一假设：标记西格陵兰岛和巴芬岛前冰范围的突出冰碛系统记录了格陵兰岛和巴芬岛的同步推进。 9.3 年前和 8200 年前的突然变冷事件驱动了劳伦泰德冰盖。试点数据显示，与周围海洋接触的冰盖边缘部分能够对短暂的气候扰动做出快速反应。为了测试这些记录的变化是否仅限于最敏感的海洋终止冰盖部分，或者冰盖是否能够对百年规模的气候变化做出更大规模的反应，需要从其他方面对冰盖变化进行严格约束的年表。地区。研究人员的研究目标是：1）确定冰盖的陆地终端区域（更能代表更广泛的冰盖边缘）如何响应突然的气候变化，2）进一步评估海洋强迫在调节冰盖响应中所起的作用短期气候扰动，3）重建山地冰川系统的全新世早期行为（夏季温度的代表），以评估影响冰盖的气候条件。调查人员将努力让公众更容易获得结果。这项工作由一名早期职业调查员领导，将为两名研究生和几名本科生提供支持。