EAR-PF: The Rapid Response of Permafrost (RRP) to Intense Day-Long and Season-Long Climate Warming

EAR-PF：永久冻土层 (RRP) 对全天和全季气候变暖的快速响应

• 批准号: 2204594
• 负责人: Cansu Culha
• 金额: $ 18万
• 依托单位: Culha, Cansu
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2204594&HistoricalAwards=false
• 关键词: EAR; PF; Rapid; Response; Permafrost

Approximately 85% of the Alaskan landscape, more than half of Alaskan communities, 75% of Alaskan pipelines, and 80% of state-owned Alaskan roads are on periglacial land -- an active soil layer that undergoes seasonal freeze-thaw cycles, supported by a deeper frozen layer called permafrost. Global warming accelerates melting, thinning and weakening of permafrost, which raises concerns for the stability of periglacial landscapes and the sustainability of critical infrastructure. Furthermore, land surface failures in periglacial environments can deliver large quantities of sediment, metals, and bacterial life to fragile local and coastal watershed ecologies, as well as release greenhouse gasses to the atmosphere. A vital part of government and industry response to climate change will be tools that manage the unprecedented hazards of permafrost in periglacial landscapes. Dr. Culha will characterize the underlying physics of these tools. One objective is to create models that predict the different types of periglacial response to rapid, intense warming, like seasonal heat waves. A second objective is to develop a novel interactive application that can support national and local Arctic community leaders in the rapid permafrost response, as well as to use community inputs to train and enhance her models.During July 2019, one of the hottest on record, collaborators documented a 100-meter wide ``retrogressive thaw slump," an unprecedented periglacial landscape response to rapid, intense warming. This horseshoe shaped landscape failure has since formed a stream from the melting permafrost, delivering silty water to a nearby watershed. Landscape failures like retrogressive thaw slumps and water draining events can pose risks not just to critical infrastructure such as roads, oil pipelines and schools but potentially to the sustainability of indigenous populations across the Canadian Arctic and in parts of Alaska. The risks may also cause these indigenous populations to relocate or rebuild if the failures lead to clogged fresh water resources, damaged fisheries and altered ecological habitats. Furthermore, landscape failure events are associated with the release of permafrost-trapped gasses, metals, nutrients and pathogens into the ecosystem. Thus, the effects of periglacial landscape failure are not limited to the failure area. A key proposal objective is to develop a regime diagram of the different permafrost responses as a function of landscape and climatic characteristics. The models from this objective will enable the development of hazard maps of periglacial landscapes. A second major objective is the development of a practical interactive digital tool that applies the predictive hazard maps to provide instantaneous risk assessments. For example, through this application, water agencies can quantify vulnerability to sediment bombardment from land failures, fisheries can extract probabilities for increased sediment delivery and metal leaching, and natural disaster agencies can estimate the regional extents and infrastructure that are most vulnerable to permafrost landscape collapse. With user input, the application can further help test and improve the accuracy of the models. This proposal will use field observations with unprecedented spatial and temporal resolution from Axel Heiberg Island, novel computational physical models, data science and traditional knowledge to characterize, understand, and disseminate emerging hazards and critical risks of these summer warming events.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.

大约85%的阿拉斯加地貌、超过一半的阿拉斯加社区、75%的阿拉斯加管道和80%的国有阿拉斯加道路位于冰缘土地上--冰缘土地是一种经历季节性冻融循环的活跃土层，由更深的冻土层支撑，称为永冻层。全球变暖加速了永久冻土的融化、变薄和削弱，这引起了人们对冰缘地貌的稳定性和关键基础设施的可持续性的担忧。此外，冰缘环境中的陆面破坏可能会给脆弱的当地和沿海流域生态系统带来大量的沉积物、金属和细菌生命，并向大气释放温室气体。政府和行业应对气候变化的一个重要部分将是管理冰缘景观中史无前例的永久冻土危害的工具。库哈博士将描述这些工具的基本物理特性。其中一个目标是建立模型，预测冰缘对快速、强烈的变暖的不同类型的反应，比如季节性热浪。第二个目标是开发一种新的互动应用程序，可以支持国家和地方北极社区领导人对永久冻土的快速反应，并利用社区投入来培训和增强她的模型。在2019年7月，有记录以来最热的之一，合作者记录了100米宽的“退行性融化滑坡”，这是一种史无前例的冰缘景观对快速、强烈变暖的反应。自那以后，这种马蹄形的景观崩塌从融化的永久冻土中形成了一条小溪，将淤泥状的水输送到附近的分水岭。退行性融化滑坡和排水事件等景观故障不仅可能对道路、输油管道和学校等关键基础设施构成风险，还可能对加拿大北极地区和阿拉斯加部分地区土著居民的可持续性构成风险。如果失败导致淡水资源堵塞、渔业受损和生态生境改变，风险还可能导致这些土著人口搬迁或重建。此外，景观破坏事件与永久冻土捕获的气体、金属、营养物质和病原体释放到生态系统中有关。因此，冰缘景观破坏的影响并不局限于破坏区域。建议的一个关键目标是根据地貌和气候特征，绘制不同永冻层响应的状况图。根据这一目标建立的模型将有助于开发冰川周围地貌的危险地图。第二个主要目标是开发一种实用的交互式数字工具，该工具应用预测危险图来提供瞬时风险评估。例如，通过这一应用，水机构可以量化土地破坏造成的泥沙轰炸的脆弱性，渔业可以提取增加泥沙输送和金属淋溶的可能性，自然灾害机构可以估计最容易受到永久冻土景观坍塌影响的区域范围和基础设施。有了用户的输入，该应用程序可以进一步帮助测试和提高模型的准确性。这项提议将使用来自阿克塞尔·海贝格岛的具有前所未有的时空分辨率的现场观测、新的计算物理模型、数据科学和传统知识来表征、理解和传播这些夏季变暖事件的新出现的危险和关键风险。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。