RAPID: Fingerprinting new water-carbon interactions in the Arctic: Isotopic measurements through the Northwest Passage and in Baffin Bay

RAPID：对北极新的水-碳相互作用进行指纹识别：通过西北航道和巴芬湾的同位素测量

• 批准号: 2133156
• 负责人: Jeffrey Welker
• 金额: $ 20万
• 依托单位: University of Alaska Anchorage Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-06-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2133156&HistoricalAwards=false
• 关键词: RAPID; Fingerprinting; new; water; carbon

The Arctic carbon and water cycles are undergoing fundamental changes as the Arctic experiences an entire suite of new conditions. At the core of this restructuring is rapid Arctic warming, the loss of sea ice, shifting atmospheric and ocean circulation patterns, increasing precipitation, permafrost thaw, and enhanced melt of the Greenland Ice Sheet and other mountain glaciers and ice caps. These changes have resulted in the simultaneous freshening of the Arctic seas and humidification of the Arctic atmosphere due to more evaporation from what was previously ice-covered ocean. Concurrently, riverine discharges are driving the fertilization of the Arctic seas and increasing ocean water productivity by carrying ancient carbon and old nutrients from thawed permafrost into the fjords, bays, and ocean. It is urgent to monitor and quantify these new ice-ocean-land-atmosphere interactions to understand the magnitude and variability of carbon and water cycle changes across the Arctic. This project capitalizes on an autumn 2021 research expedition of the USCGC Healy Icebreaker. The project will use continuous isotope fingerprinting to delineate key linkages between ice-ocean-land-atmosphere interactions along the west coast of Alaska, through the Northwest Passage and in Baffin Bay. The project will measure carbon and water isotopes of marine air and ocean water continuously with some spot intense sampling locations. These measurements will enable quantification of the geochemical patterns that record freshening, fertilization, evaporation, and productivity variations driven by differing degrees of ice-ocean-land-atmosphere interactions. These data will be the first of their kind in terms of coordination at this large scale with a transect spanning ~15 degrees of latitude and over 100 degrees of longitude in the western and central Arctic. This project will: 1) delineate the intensity of land-ice freshwater injections including the extent to which these freshwater plumes carry new sources of ancient (permafrost derived) carbon and nutrients that may drive productivity increases and ocean carbon exchange; 2) quantify the connectivity of and mechanisms controlling Arctic Ocean water evaporation and atmospheric humidification which may be altering precipitation patterns in the Arctic and in the mid-latitudes; and 3) determine ocean carbon gain or loss continuously across the Arctic seas with implications for marine food webs, support of subsistence hunting, and climate warming via atmospheric carbon dioxide and methane concentrations. This project will offer valuable contributions and data to studies of Arctic change by groups examining changing atmospheric, ocean, cryospheric processes, and marine and terrestrial ecosystems.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.

北极的碳和水循环正在发生根本性的变化，因为北极经历了一整套新的条件。这种结构调整的核心是北极迅速变暖，海冰消失，大气和海洋环流模式改变，降水增加，永久冻土融化，格陵兰冰盖和其他山地冰川和冰盖融化加剧。这些变化导致了北极海洋的清新和北极大气的潮湿，这是由于以前被冰覆盖的海洋蒸发更多。与此同时，河流排放正在推动北极海域的施肥，并通过将融化的永久冻土中的古老碳和古老营养物质带入峡湾，海湾和海洋来提高海水生产力。迫切需要监测和量化这些新的冰-海洋-陆地-大气相互作用，以了解整个北极地区碳和水循环变化的幅度和可变性。该项目利用了USCGC Healy Icebreaker的2021年秋季研究考察。该项目将利用连续的同位素指纹技术，通过西北航道和巴芬湾，描绘沿阿拉斯加西海岸沿着冰-海洋-陆地-大气相互作用之间的关键联系。该项目将连续测量海洋空气和海水的碳和水同位素，并在一些地点进行密集采样。这些测量将能够量化地球化学模式，这些模式记录了不同程度的冰-海洋-陆地-大气相互作用所驱动的淡水化，施肥，蒸发和生产力变化。这些数据将是此类数据中首次在北极西部和中部进行大规模协调，其样带跨越约15度纬度和100多度经度。该项目将：1）描绘陆冰淡水注入的强度，包括这些淡水羽流携带新的古代淡水来源的程度。（永久冻土衍生的）碳和营养物可能推动生产力的提高和海洋碳交换; 2）量化北冰洋水蒸发和大气增湿的连通性和控制机制，这可能改变北极和中纬度地区的降水模式; 3）确定北极海洋碳的持续增加或损失，并通过大气中二氧化碳和甲烷浓度对海洋食物网、维持生计的狩猎和气候变暖产生影响。该项目将为研究不断变化的大气、海洋、冰冻圈过程以及海洋和陆地生态系统的团体对北极变化的研究提供有价值的贡献和数据。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。