CAREER: Follow the Water: Understanding River Discharge Dynamics in Rapidly Changing High Northern Latitudes

职业：跟随水流：了解快速变化的北高纬度地区的河流流量动态

• 批准号: 2238368
• 负责人: Eric Klein
• 金额: $ 84.05万
• 依托单位: University of Alaska Anchorage Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2028-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2238368&HistoricalAwards=false
• 关键词: CAREER; Follow; Water; Understanding; River

The Arctic region is rapidly changing as average air temperatures, rainfall, glacier and ice sheet melt rates, and permafrost depths all increase. However, the connections between these processes and how they influence the discharge, source, and nutrient concentrations of water in Arctic rivers are not well understood. To characterize shifting river source contributions and bridge this knowledge gap, this project will measure multiple components of the water cycle in permafrost watersheds across a range of glacial coverages (including glacier free) in Greenland. Models will test the hypothesis that in the warmer and wetter future Arctic, contributions from flow through the ground to the river will both increase and persist later in the season, which will help offset the loss of river water from steadily decreasing ice masses. Research and education are integrated by collaborating with the Alaska Native Science and Engineering Program, research institutions in Greenland, the Belfer Center’s Arctic Initiative at Harvard University, local Greenland communities, and the University of the Arctic Læra Institute to develop a powerful platform that increases Indigenous Alaskan and Greenland student participation in hydrology. This platform includes programs like Greenland field research opportunities for Indigenous Alaskan and Greenland students and development of Arctic water cycle focused courses. Three important hydrological shifts associated with a warmer and wetter High Arctic Greenland occurred within the last million years: 1) increased freshwater from glacier melt; 2) deepening active layer (permafrost thaw); and 3) increased precipitation. Current climate changes are leading to an Arctic Greenland more like these past environments. A warmer Arctic will likely increase active layer depths, which when coupled with greater rain expected in the Arctic, could result in more flow through the active layer contributing to river discharge, but this remains unknown. This project will measure multiple components of the water cycle in permafrost watersheds across a range of glacial coverages (including glacier free) in High Arctic Greenland. These data will characterize shifting river source contributions and provide critical field data needed to calibrate novel numerical hydrological models. These models will then help test river discharge hypotheses given future Arctic change under different climate scenarios (e.g., more precipitation, deeper active layer). These analyses will help understand how increased active layer flow could mitigate the hydrological impact of glacier recession and future transition to ice-free watersheds. This project will support graduate and undergraduate students and develop a powerful multifaceted platform to increase participation in STEM fields of Indigenous Alaskan and Greenland students. A new Arctic focused hydrology course will be taught via distance delivery and leverage relationships to bring together Indigenous Alaskan and Greenland students. This project will also provide Indigenous Alaskan and Greenland undergraduate students with a transformative experience learning together in the field while working with researchers. Larger societal benefits include understanding how the Arctic water cycle is changing, which can impact the global water cycle, freshwater resources, and climate patterns across Earth.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.

随着平均空气温度，降雨量，冰川和冰盖融化的速度以及永久冻土深度都增加，北极区域正在迅速变化。但是，这些过程之间的连接及其如何影响北极河中水的排放，来源和营养浓度尚不清楚。为了表征转移的河流贡献并弥合了这一知识差距，该项目将在格陵兰岛的一系列冰川覆盖范围（包括无冰川）的多种冻土流域中测量水循环的多个组成部分。模型将检验以下假设：在较温暖和潮湿的未来北极，从地面流到河流的贡献将在本季节晚些时候增加并持续存在，这将有助于抵消静静地减少冰块的流失。研究和教育是通过与阿拉斯加土著科学与工程计划，格陵兰的研究机构，贝尔弗中心的北极计划，哈佛大学，当地的格陵兰社区和北极Læra大学开发一个强大的平台，以增加阿拉斯加和格林兰学生参与水文学的强大平台，从而整合研究和教育。该平台包括为阿拉斯加土著人和格陵兰学生提供的格陵兰实地研究机会以及北极水循环集中的课程的开发。在过去的百万年内发生了与较温暖和潮湿的高北极格陵兰相关的三个重要的水文转移：1）冰川融化的淡水增加； 2）加深活性层（永久冻结）； 3）增加降水量。当前的气候变化导致北极格陵兰更像过去的环境。温暖的北极可能会增加活跃的层深度，而当北极期间预期的降雨时，这可能会导致更多的流动层导致河流排放的活性层，但这仍然未知。该项目将测量在高北极格陵兰岛的多个冰川覆盖范围（包括冰川无冰川）的多种冻土流域中水循环的多个组成部分。这些数据将表征转移的河流贡献，并提供校准新型数值水文模型所需的关键现场数据。这些模型随后将有助于测试河流排放假设，因为在不同的气候场景（例如，更多的降水，更深的活性层）下，将来的北极变化。这些分析将有助于了解增加的活性层流如何减轻冰川衰退和未来过渡到无冰流域的氢影响。该项目将支持毕业生和本科生，并开发一个强大的多方面平台，以增加参与阿拉斯加土著和格陵兰学生的STEM领域。将通过远程交付和利用关系来召集新的以北极为中心的水文学课程，以召集阿拉斯加土著和格陵兰学生。该项目还将为阿拉斯加土著和格陵兰本科生提供与研究人员合作时在现场学习的变革经验。更大的社会益处包括了解北极水周期的变化，这可能会影响全球水周期，淡水资源和地球的气候模式。该奖项反映了NSF的法定任务，并被认为是通过基金会的知识分子和更广泛影响的评估来审查标准的评估。