Collaborative Research: Resolving centennial- to millennial-scale trends in glacier extent and lake sedimentation in the Brooks Range, Arctic Alaska

合作研究：解决阿拉斯加北极地区布鲁克斯山脉冰川范围和湖泊沉积的百年至千年尺度趋势

• 批准号: 1107647
• 负责人: Michael Retelle
• 金额: $ 1.63万
• 依托单位: Bates College
• 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: 2011-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1107647&HistoricalAwards=false
• 关键词: Collaborative; Research; Resolving; centennial; millennial

The goal of this collaborative project to reconstruct late Quaternary climate and glacier change in Arctic Alaska, one of few regions in the Arctic where mountain glaciers have left physical records of their former extent, making it valuable for comparing the timing and extent of mountain glacier variability between the lower latitudes and the Arctic. Several features of the climate and glacier history of the Brooks Range contrast with those from the North Atlantic region (which is often taken to represent the entire Northern Hemisphere in records of climate change) and currently available evidence indicates that the history of the Brooks Range more closely resembles glacier records from the southern Hemisphere. The investigators propose to develop records of climate change from lake sediments and records of glacier fluctuations using proglacial lake sediments and beryllium-10 dating of glacial features to address questions centered around four intervals of pronounced global change: (1) Last Glacial Maximum: Did glaciers retreat and temperatures increase in Arctic Alaska during the global LGM, as has been simulated by climate models? (2) Deglaciation: To what extent did climate change in Arctic Alaska coincide with North Atlantic climate fluctuations during deglaciation? (3) Holocene Glaciation: What was the extent of glaciers during (a) the Holocene thermal maximum, and (b) Neoglaciation? (4) Little Ice Age: Was it wetter or drier in the Brooks Range? The research will take place in suitable valleys (floatplane accessible valley with extant glaciers) in the north­central Brooks Range. The project has several educational components, including support four graduate students and several undergraduate students and visits to the community of Anaktuvuk Pass to deliver presentations on climate research and the Brooks Range. The proposed research aims to produce well-dated and quantitative records of glacier and climate variability in the northernmost glaciated region of the U.S. Documenting the past behavior of arctic glaciers when subject to extreme climate events during the late glacial period and warm intervals like the Holocene can provide valuable insight to help better predict responses to future change.

这项合作项目的目的是重建阿拉斯加北极地区晚期气候和冰川变化，这是北极地区的少数地区之一，在该地区，山冰川留下了以前的物理记录，使其对比较山地冰川变异性的时间和程度很高。布鲁克斯范围的气候和冰川历史的几个特征与北大西洋地区的气候范围（通常是代表整个北半球的气候变化记录中）形成鲜明对比的，目前可用的证据表明，布鲁克斯的历史范围更像是来自南半球的冰川记录。研究人员建议开发从湖泊沉积物的气候变化记录以及使用前冰湖沉积物和冰川-10的冰川波动记录的记录，以解决冰川特征的日期，以解决围绕明显全球变化的四个间隔的问题：（1）最后冰川最大值：冰川静修和温度在全球alaska中的模型增加了吗？ （2）脱气：北极阿拉斯加气候变化与北大西洋气候在脱气期间的气候变化在多大程度上是一致的？ （3）全新世冰川：（a）全新世热最大值和（b）新摩尼语的冰川程度是多少？ （4）冰河时代很小：在布鲁克斯范围内它湿或驾驶员？这项研究将在中央布鲁克斯山脉的合适山谷（带有广泛冰川的浮力山谷）中进行。该项目有几个教育组成部分，包括支持四名研究生和几个本科生，并访问了Anaktuvuk Pass社区，以提供有关气候研究和Brooks系列的演讲。拟议的研究旨在在美国的最大冰川区域中产生冰川和气候变异性的良好和定量记录，以记录北极冰川过去在晚期冰川期间发生极端气候事件的过去行为，而全新世之后的温暖间隔（如全新世）可以提供有价值的见识，以帮助更好地预测对未来变化的反应。