Collaborative Research: RUI: Frontal Ablation Processes on Lake-terminating Glaciers and their Role in Glacier Change

合作研究：RUI：湖终止冰川的锋面消融过程及其在冰川变化中的作用

• 批准号: 2334775
• 负责人: William Armstrong
• 金额: $ 30.34万
• 依托单位: Appalachian State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2334775&HistoricalAwards=false
• 关键词: Collaborative; Research; RUI; Frontal; Ablation

Glaciers around the world are changing rapidly in response to warming temperatures. Glaciers that end in water often thin and retreat faster than those ending on land because they lose ice through melt below the waterline and through the breaking off of icebergs. While many past researchers have studied the workings of glaciers ending in the ocean, very few have focused on glaciers that end in lakes and how these two types of glaciers might function differently. In our project, we will study a set of three glaciers that end in lakes; collecting information about the glaciers themselves, the lakes they end in, and the sediment moving between the glacier and lake. The investigators will work with students from two different programs in Alaska to identify how much extra ice is being lost due to these lakes and how much that ice loss matters for how the glaciers will change over the coming decades.Globally, lakes at the end of glaciers have grown rapidly over the past decades. However, it remains unclear whether lakes are growing as a passive response to glacier retreat that is largely driven by changing atmospheric conditions (warming air temperature and/or declining winter snowfall), or whether the lakes themselves are driving this retreat by enabling extra ice loss. Our team brings together a glaciologist, an oceanographer, and an Arctic earth system modeler to quantify the amount of ice lost through iceberg production and underwater melt on three large glaciers draining the Juneau Icefield that end in lakes. The investigators will collect both short- and long-term observations of conditions in the lake (depth, temperature, suspended sediment concentration) using a sonar system and probes cast from a boat, as well as buoy-mounted instruments. The investigators will also measure glacier ice thickness and speed using ground-based radar, GPS systems, and satellite observations. These datasets will be fed into computer models to estimate how much additional ice is being lost due to the lake, how this will change in the future, and how much the lake’s presence will alter the glacier’s overall ice loss over the 21st century. This information will help us understand how fast glaciers across the world will change over the coming decades, which will enable better management of downstream ecosystems and water resources, as well as promoting climate change resilience. In addition to the science objectives, the project will strengthen the STEM workforce by partnering with undergraduate programs to develop computational workshops and broaden representation within the earth science community.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.

世界各地的冰川正在因气温升高而迅速变化，终止于水中的冰川通常比终止于陆地的冰川变薄且退缩得更快，因为它们会通过水线以下的融化和冰山的脱落而失去冰块，而过去的许多研究人员已经做到了这一点。研究了终止于海洋的冰川的运作，很少有人关注终止于湖泊的冰川以及这两种类型的冰川如何以不同的方式发挥作用。在我们的项目中，我们将研究一组终止于湖泊的三个冰川。湖泊；收集有关冰川本身、冰川终止的湖泊以及冰川和湖泊之间沉积物移动的信息，调查人员将与阿拉斯加两个不同项目的学生合作，以确定由于这些湖泊而流失的额外冰量。冰的流失对未来几十年冰川的变化有多大影响。在全球范围内，冰川末端的湖泊在过去几十年里迅速增长。然而，目前尚不清楚湖泊的增长是否是对冰川的被动反应。冰川退缩主要是由大气条件变化（气温升高和/或冬季降雪量减少）驱动的，或者湖泊本身是否通过导致额外的冰损失来驱动冰川退缩。我们的团队汇集了冰川学家、海洋学家和北极专家。地球系统模型对朱诺冰原最终形成湖泊的三个大型冰川的冰山产生和水下融化损失的冰量进行量化。调查人员将收集湖泊状况的短期和长期观测结果。研究人员还将使用声纳系统和船上的探头以及浮标安装的仪器来测量冰川冰的厚度和速度，这些数据集包括地面雷达、GPS 系统和卫星观测数据。将被输入到计算机模型中，以估计由于该湖而损失了多少额外的冰，未来将如何变化，以及该湖的存在将在多大程度上改变 21 世纪冰川的整体冰损失。我们了解未来几十年世界各地冰川变化的速度，这将有助于更好地管理下游生态系统和水资源，并提高气候变化的抵御能力。除了科学目标外，该项目还将通过合作加强 STEM 劳动力。与本科生项目一起开展计算研讨会并扩大地球科学界的代表性。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。