Collaborative Research: The demise of the world's largest piedmont glacier

合作研究：世界上最大的山麓冰川的消亡

• 批准号: 1929566
• 负责人: Martin Truffer
• 金额: $ 83.3万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1929566&HistoricalAwards=false
• 关键词: Collaborative; Research; demise; world; largest

Located on the coast of Southeast Alaska, Malaspina Glacier is the world’s largest piedmont glacier, a type of glacier that starts in the mountains and spills out onto the coastal plain. The Malaspina Glacier is currently rapidly thinning and retreating, forming a series of proglacial lakes along the bottom edge. Some of these lakes are only separated from the open ocean by a narrow band of sediment moraine. The underside of the glacier is located well below sea level and all current indications are that retreat and thinning will continue, and most likely accelerate, even with little future climate change. This has the potential to be the largest loss of ice in Alaska from one glacier in the next several decades. As the Malaspina Glacier retreats and thins it will transform the landscape, exposing more rocks and moraine, creating new lakes, and/or leading to significant changes in the coastline, such as the formation of marine fjords. If this happens, it will be one of the largest modern changes to Alaska’s and the nation’s coastline with large impacts to both terrestrial and marine ecosystems. These changes would also constitute the largest single change in terrestrial land cover in the National Park system in recent history.The main goal of this work is to use a computer model to estimate what the future could look like for the Malaspina Glacier and surrounding area. Measurements collected in the field, on and around the glacier, will provide the necessary model input data. The work will result in a comprehensive data set on glacier mass balance, ice velocity, ice thickness, glacier bed conditions, surface debris extent and thickness, proglacial lake development, and proglacial thermokarst evolution. These data will be ingested into a numerical model that will be used to explore a large range of possible future scenarios for the evolution of Malaspina Glacier. The model scenarios will account for different climate trajectories as well as uncertainties of model parameters, such as those associated with hydrology and motion at the underside of the glacier. Specifically, the following questions will be addressed:1. Is a pathway from the ocean to the glacier front critical for catastrophic retreat?2. Will the retreat of Malaspina be dominated by surface mass balance?3. What are the main uncertainties for model predictions?This work will lead to a better understanding of how climate change interacts with dynamic instabilities that are independent of climate, in an area that has historically been characterized by large glacier fluctuations and spatial and temporal variability. While dynamically caused retreats are common for coastal glaciers, these effects are amplified in the presence of ongoing warming.Malaspina Glacier is located in the Wrangell-St. Elias National Park and has the potential to help people envision the potentially dramatic effects of climate change on the Earth’s cryosphere. A graphic artist will convert the model results into striking visuals that show the opening up of a new landscape. Using an online message testing experiment, the project will test and develop outreach materials to increase visitor knowledge of ongoing and anticipated future glacier change and climate change. Visuals and associated information will become interactive exhibits that will engage thousands of visitors at the Wrangell-St. Elias National Park visitor center and online. In addition, this project will train three graduate students in relevant geophysical techniques, modern ice sheet modeling approaches, and collaborative research. The project outcomes will be published in peer-reviewed literature and presented at professional meetings.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.

东南马拉斯皮纳冰川位于阿拉斯加海岸，是世界上最大的山麓冰川，是一种从山脉开始延伸到沿海平原的冰川，目前马拉斯皮纳冰川正在迅速变薄和后退，形成一系列前冰川湖。其中一些湖泊仅通过一条狭窄的沉积冰碛带与开阔的海洋隔开，冰川的底部远低于海平面。即使未来气候变化不大，退缩和变薄仍将继续，而且很可能会加速，随着马拉斯皮纳冰川的退缩和变薄，这有可能成为阿拉斯加最大的冰川流失。将改变地貌，暴露更多的岩石和冰碛，形成新的湖泊，和/或导致海岸线发生重大变化，例如海洋峡湾的形成。如果这种情况发生，这将是阿拉斯加和阿拉斯加现代最大的变化之一。这这些变化也将构成国家公园系统近代史上最大的陆地覆盖变化。这项工作的主要目标是使用计算机模型来估计这些变化。马拉斯皮纳冰川及周边地区的未来可能是这样的，在冰川上和周围收集的测量结果将提供必要的模型输入数据，这项工作将产生有关冰川质量平衡、冰的综合数据集。速度、冰厚度、冰川床条件、表面碎片范围和厚度、冰期湖泊发育以及冰期热岩溶演化这些数据将被纳入一个数值模型，该模型将用于探索未来各种可能的演化情景。马拉斯皮纳冰川。该模型将考虑不同的气候轨迹以及模型参数的不确定性，例如与冰川底部的水文和运动相关的参数。具体来说，将解决以下问题：1。从海洋到冰川前缘的路径对灾难性退缩至关重要吗？2. 马拉斯皮纳的退缩是否会受表面质量平衡的影响？3. 模型预测的主要不确定性是什么？气候变化与独立于气候的动态不稳定性相互作用，该地区历史上一直以冰川大幅波动和时空变化为特征，虽然动态引起的退缩对于沿海冰川来说很常见，但这些影响在沿海冰川中被放大。马拉斯皮纳冰川位于兰格尔-圣埃利亚斯国家公园，有潜力帮助人们想象气候变化对地球冰冻圈潜在的巨大影响。一位图形艺术家将把模型结果转换成引人注目的视觉效果。通过在线信息测试实验，该项目将测试和开发宣传材料，以增加游客对正在进行和预期的未来冰川变化和气候变化的了解。视觉效果和相关信息将成为互动展览。吸引数千人此外，该项目还将在相关地球物理技术、现代冰盖建模方法和合作研究方面对三名研究生进行培训。审查文献并在专业会议上颁发。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。