COLLABORATIVE RESEARCH: Ice Regime Shifts of Arctic Lakes Drive Interactions and Feedbacks with Permafrost and Climate

合作研究：北极湖泊的冰情变化驱动与永久冻土和气候的相互作用和反馈

• 批准号: 1417300
• 负责人: Christopher Arp
• 金额: $ 122.59万
• 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: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1417300&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Ice; Regime; Shifts

Shallow lakes and ponds may cover up to 40 percent of the land surface in Arctic lowland regions. Many of these water bodies traditionally freeze solid during the winter, preserving sub-lake permafrost and keeping soil carbon stocks immobile at depth. Slightly deeper lakes maintain some liquid water beneath floating ice, causing deep thaw zones in otherwise continuous permafrost. Evidence suggests that thinner ice growth in response to warmer, snowier winters is pushing many bedfast ice lakes to floating ice regimes. If such a regime shift becomes pervasive across lake-rich landscapes, resulting permafrost thaw and enhanced moisture and heat flux could generate positive feedbacks, further amplifying this regime change. This project examines the extent and dynamics of bedfast and floating ice lakes in relation to hypothesized interactions and feedback with permafrost and climate. A combination of remote sensing, field monitoring and geophysical measurements, experiments and physical models are used to isolate processes, quantify interactions and project changes. Project findings will be relevant locally for native village subsistence and for water supply to the petroleum industry, and globally for scientists studying permafrost thaw and Arctic climate change.

在北极低地地区，浅水湖泊和池塘可能覆盖多达40%的陆地表面。 这些水体中的许多在冬季通常会冻结成固体，保护了湖底的永久冻土，并使土壤碳储存在深处保持不动。 稍深的湖泊在浮冰下保持了一些液态水，在连续的永久冻土中形成了深解冻区。 有证据表明，随着冬季的变暖和降雪，冰层的增长越来越薄，这使得许多固定的冰湖变成了浮冰。 如果这种制度转变在湖泊丰富的景观中变得普遍，那么永久冻土融化和增强的水分和热通量可能会产生正反馈，进一步放大这种制度变化。本项目研究了与永久冻土和气候的假设相互作用和反馈有关的固定床和浮冰湖的范围和动态。 将遥感、实地监测和地球物理测量、实验和物理模型相结合，用于分离过程、量化相互作用和项目变化。 项目的研究结果将在当地与土著村庄的生存和石油工业的供水有关，并在全球范围内与研究永久冻土融化和北极气候变化的科学家有关。