Benchmarking Spatial Patterns of Glacier Change

这项研究将调查过去冰川前进和后退的全球模式，以分析环境变化的区域模式。 在全球冰川衰退期间，世界不同地区的冰川表现不同。冰川退缩的速度随时间而变化，在某些情况下，冰川退缩被短暂的冰川增长所打断。 这些不同的空间模式可以帮助科学家预测未来区域对全球环境变化的反应模式。 在这个项目中，利用各种地球科学技术，研究人员将分析阿拉斯加的冰川地貌，以确认过去冰川变化率的区域差异。 阿拉斯加是一个过去冰川变化不如世界其他地区了解的地区，但该地区的冰川变化与全球模式不同。 研究结果将有助于更好地了解过去的区域环境变异性，从而成为未来建模的重要数据来源。 该项目更广泛的影响包括来自代表性不足群体的一名科学家的职业发展，并包括对研究生和本科生的培训。传播将包括通过阿拉斯加的国家公园和土著社区传播学术出版物和面向公众的材料。为了更好地了解未来冰川变化的轨迹和相关的环境变化，必须阐明对全球冰川行为的更好的区域影响。因此，区域冰川变化及其与全球格局的偏离的详细知识是古气候和冰川地貌学界迫切需要的。最后一次冰川消退期间的二氧化碳变化与山地冰川变化紧密相关。然而，这份汇编缺乏高纬度地区的数据。 最近的研究假设，现代二氧化碳已经压倒了区域驱动因素，并已成为冰川变化的主要控制因素。拟议的研究旨在通过填补关键数据缺口来解决这些想法。 研究人员将测试两个处于古气候和冰川科学前沿的假设。(1)大气二氧化碳是山地冰川变化的主要强迫机制。 (2)北大西洋地区以外的冰川在海因里希stadiales前进，但在其终止之前退缩。研究人员将重建北方高纬度地区高度详细的山地冰川记录，时间跨度从最后一次冰消期到现在。由于大陆冰盖在冰河时代覆盖了北方大部分高纬度地区，因此很少有可访问的网站提供详细的冰川冰碛序列，并提供可以精确测年的材料。 由于阿拉斯加在末次冰期基本上没有受到大陆架的影响，而是以山地冰川为主，因此这是一个理想的基准点，并记录了自末次冰消期以来的冰川变化。 该PI将结合联合收割机宇宙成因的BERGINE-10测年的一个特殊的冰碛序列在阿拉斯加西部的启示山脉与数字制图和冰川平衡线海拔高度分析，以测试他们的假设和基准山区冰川变化的区域记录。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用该基金会的智力价值和更广泛的影响审查标准的支持。

This research will investigate global patterns of past glacier advance and retreat to analyze regional patterns of environmental variability. During times of global glacier recession, glaciers in different parts of the world behaved differently. The rate of glacier retreat varied through time, and in some cases, glacier retreat was interrupted by short intervals of glacier growth. These differential spatial patterns can help scientists predict future patterns of regional response to global environmental variability. In this project, using various earth science techniques, investigators will analyze glacial landforms in Alaska to affirm regional differences in rates of past glacier change. Alaska is a region where past glacier change is less well understood than other parts of the world, but one where regional glacier change was different from global patterns. Findings will contribute to an improved understanding of past regional environmental variability and thereby be an important data source for future modelling. The project's broader impacts include the career advancement of a scientist from an underrepresented group and includes the training of graduate and undergraduate students. Dissemination will include academic publications and public-oriented materials disseminated via national parks and native communities in Alaska. To better understand the trajectory of future glacier change, and related environmental variability, better regional influences on glacier behavior across the planet must be elucidated. For this reason, detailed knowledge of regional glacier change and their deviations from the global pattern are critically needed for paleoclimate and glacial-geomorphology communities. Carbon dioxide changes during the last deglaciation were tightly coupled to mountain glacier change. Yet, this compilation lacked data from the high latitudes. Recent research hypothesizes that carbon dioxide in modern times has overwhelmed regional drivers and has become the dominant control on glacier change. The proposed research aims address these ideas by filling in a key data gap. The investigators will test two hypotheses that are at the forefront of paleoclimate and glacier science. (1) Atmospheric carbon dioxide is the primary forcing mechanism of mountain glacier change. (2) Glaciers outside the North Atlantic region advanced during Heinrich stadials, but retreated prior to their terminations. The researchers will reconstruct a highly detailed mountain glacier record from the high northern latitudes, temporally spanning from the last deglaciation to the present. Because continental ice sheets covered most of the high northern latitudes during Ice Ages, there are few accessible sites that offer detailed glacier moraine sequences with materials that can be precisely dated. Because Alaska remained largely untouched by continental sheets during the last glacial period and was instead dominated by mountain glaciers, this is an ideal location to benchmark and develop a record of glacier change since last deglaciation. The PIs will combine cosmogenic Beryllium-10 dating of an exceptional moraine sequence in the Revelation Mountains in western Alaska with digital mapping and glacier equilibrium-line altitude analysis to test their hypotheses and to benchmark a regional record of mountain glacier change.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.