The influence of subglacial discharge on the oceanic fate of meltwater from the Greenland ice sheet

冰下排放对格陵兰冰盖融水海洋命运的影响

• 批准号: 2212654
• 负责人: Hilde Oliver
• 金额: $ 30.59万
• 依托单位: Woods Hole Oceanographic Institution
• 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: 2022-10-01 至 2025-09-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2212654&HistoricalAwards=false
• 关键词: influence; subglacial; discharge; oceanic; fate

This study concentrates on the influence that melt waters from Greenland fjords has on the circulation of the Labrador Sea to determine the fate of the melt water to the North Atlantic Ocean. The premise of the proposal is that fresh water discharged from glaciers and trapped below the ocean’s surface on East Greenland has different fate from the fresh water that reaches the surface. The difference in destination between surface and subsurface fresh waters is because the wind should drive surface waters distinctly from subsurface waters, which are more isolated from the wind forcing. The study will be carried out with computer model simulations and satellite data. Findings from this study should have implications for global scale models that study water sinking in the North Atlantic and its impact on climate. The project will support one graduate student and will organize a workshop on climate processes for math & science teachers in Georgia.This project will investigate transport processes in the Labrador Sea, from areas of direct influence of Greenland ice sheet melt water to areas in the Labrador Sea where deep convection occurs in winter. The goal of the proposal is to identify and quantify the effect of subglacial discharge on transport pathways in the Labrador Sea. The hypothesis is that subsurface melt water from East Greenland’s fjords will be transported to the Labrador Sea more effectively than surface melt water. If this hypothesis is proven accurate, then it will show that the correct depiction of fjord circulation is essential for representation of large-scale circulation and convection in ocean models. The proposal also hypothesizes that, with global warming, outflow plumes will either a) be more influenced by winds off W Greenland and reduce transport of melt water into central Labrador Sea, or b) increase flow instabilities and spatial variability that will increase transport into central Labrador Sea. Satellite observations and model simulations will quantify the relative importance of the two possible outcomes of the latter hypothesis and the effects of melt water on winter convection. The work is justified by the need to represent subglacial discharge on eastern Greenland, in contrast to the surface input of land-terminating glaciers on West Greenland. As Broader Impacts, the project will support one grad student and one research scientist, partially. The PIs will organize a 1-day workshop on climate processes for math & science teachers, as part of Georgia’s Long Term Ecological Research.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.

这项研究集中于格陵兰峡湾融化的水对拉布拉多海环流的影响，以确定融化的水进入北大西洋的命运。该提案的前提是，从东格陵兰岛冰川排放并被困在海面下的淡水与到达海面的淡水有着不同的命运。地表淡水和地下淡水在目的地上的不同是因为风应该将地表水域与地下水域区分开来，后者更多地与风的强迫隔绝。这项研究将利用计算机模型模拟和卫星数据进行。这项研究的发现应该会对研究北大西洋水下沉及其对气候影响的全球尺度模型产生影响。该项目将支持一名研究生，并将为格鲁吉亚的数学和科学教师组织一次关于气候过程的研讨会。该项目将调查拉布拉多海的运输过程，从格陵兰冰盖融化水直接影响的地区到冬季发生深对流的拉布拉多海地区。该提案的目标是确定和量化冰下排放对拉布拉多海运输路径的影响。假设来自东格陵兰峡湾的地下融水将比地表融水更有效地输送到拉布拉多海。如果这一假设被证明是准确的，那么它将表明，正确地描述峡湾环流对于在海洋模式中表示大尺度环流和对流是必不可少的。该提案还假设，随着全球变暖，流出的羽流将a)更多地受到格陵兰西部风的影响，减少融化水进入拉布拉多海中部的输送，或b)增加流动的不稳定性和空间变异性，从而增加进入拉布拉多海中部的输送。卫星观测和模型模拟将量化后一种假设的两种可能结果的相对重要性，以及融化水对冬季对流的影响。这项工作是合理的，因为需要代表格陵兰东部的冰下排放，而不是西部格陵兰陆地终止冰川的地面输入。作为更广泛的影响，该项目将部分支持一名研究生和一名研究科学家。作为佐治亚州长期生态研究的一部分，PIS将为数学和科学教师组织一个为期一天的关于气候过程的研讨会。这一奖项反映了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。

项目成果

Greenland Subglacial Discharge as a Driver of Hotspots of Increasing Coastal Chlorophyll Since the Early 2000s

自 2000 年代初以来，格陵兰岛冰下放电是沿海叶绿素增加热点的驱动因素

• DOI: 10.1029/2022gl102689
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Oliver, Hilde;Slater, Donald;Carroll, Dustin;Wood, Michael;Morlighem, Mathieu;Hopwood, Mark J.
• 通讯作者: Hopwood, Mark J.