Collaborative Research: RUI: Zero-order to first-order: Hydrologic drivers of surface-subsurface storage dynamics in thawing permafrost landscapes

合作研究：RUI：零阶到一阶：解冻永久冻土景观中地表-地下储存动态的水文驱动因素

• 批准号: 2102338
• 负责人: Sarah Evans
• 金额: $ 27.64万
• 依托单位: Appalachian State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2102338&HistoricalAwards=false
• 关键词: Collaborative; Research; RUI; Zero; order

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).Liquid water in the Arctic flows at or near the surface above frozen ground known as permafrost. As permafrost thaws, water flows along new paths, mobilizing previously frozen carbon. If permafrost soils thaw and dry, carbon is released three times more readily than if permafrost soils thaw and remain saturated, implying that water patterns partially control carbon release. Yet, the patterns or drivers of permafrost saturation and how they vary with climate remain poorly understood. This research will use field measurements, remote sensing, and modeling to investigate the dynamics, drivers, and sensitivity of hillslope saturation patterns on the North Slope of Alaska. Results will help to create an ‘H2cOld: Water in the Arctic’ traveling outreach activity for rural K-12 students and communities throughout the southern Appalachians and Idaho. The project will also train four undergraduate students and a graduate student for science careers.The hydrology of Arctic hillslopes underlain by continuous permafrost is largely controlled by water tracks, seasonally saturated zero-order features draining a third of the upland Arctic. Water tracks can rapidly degrade into thermoerosional gullies, the most common Arctic thermoerosional feature, altering seasonal saturation and fluxes of water, nutrients, and sediments. Although water tracks and thermoerosional gullies are the largest and most variable aquatic sources of permafrost carbon release, their saturation dynamics and how these dynamics change as permafrost thaws remain poorly understood. These two features are hypothesized to represent endmembers of the surface network extent of Arctic hillslope hydrology with distinct saturation patterns that are diverging as the climate warms. This research project will test this hypothesis in paired water tracks and thermoerosional gullies in northern Alaska via remote sensing and field campaigns to calibrate a water-energy transport model with variable saturation and freeze-thaw capabilities. Collectively, this work will improve predictions of saturation-controlled carbon release from the Arctic.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.

该奖项是根据2021年《美国救援计划法》（第117-2）的全部或部分资助的。随着永久冻结的融化，水沿着新路径流动，动员了以前冷冻的碳。如果永久冻土融化并干燥，碳被释放的碳比永久冻土融化并保持饱和的情况更容易释放三倍，这意味着水模式部分控制了碳释放。然而，多年冻土安全的模式或驱动因素以及它们如何随着气候变化而变化。这项研究将使用现场测量，遥感和建模来研究阿拉斯加北坡上山坡饱和模式的动态，驱动因素和灵敏度。结果将有助于通过阿巴拉契亚岛南部和爱达荷州为粗糙的K-12学生和社区提供“ H2Cold：北极的水中”旅行外展活动。该项目还将培训四名本科生和一名科学生涯的研究生。北极山坡的水文学由连续的多年冻土延伸，在很大程度上由水轨控制，季节性饱和的零级订购量占据了高地北极地区的三分之一。水轨可以迅速降解为热毛形沟渠，最常见的北极热膜特征，改变了季节性满意度和水，养分和沉积物的通量。尽管水迹和热制剂沟渠是多年冻土碳释放的最大，最可变性的水生源，但随着永久冻结融化的了解，它们的饱和动力学以及这些动态如何变化。假设这两个特征代表了北极山坡水文的表面网络范围的最终成员，并具有不同的饱和度模式，随着气候温暖的变化。研究项目将在阿拉斯加北部的配对水轨和热层沟渠中测试这一假设，并通过遥远的敏感性和现场运动来校准具有可变安全性和冻结功能的水能运输模型。总的来说，这项工作将改善对北极饱和控制的碳释放的预测。该奖项反映了NSF的法定任务，并认为使用基金会的知识分子优点和更广泛的影响评估标准，认为值得通过评估获得支持。