Land Ice Freshwater Budget of the Arctic and North Atlantic Oceans: 1. Data, Methods, and Results.
Land Ice Freshwater Budget of the Arctic and North Atlantic Oceans: 1. Data, Methods, and Results.
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DOI：
10.1002/2017jc013605
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发表时间：
2018-03
期刊：
影响因子：
--
通讯作者：
Noel B
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文献类型：
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作者：
Bamber JL;Tedstone AJ;King MD;Howat IM;Enderlin EM;van den Broeke MR;Noel B
北极和次极地北大西洋的淡水收支一直在变化，主要原因是河流径流增加，海冰减少和北极陆地冰融化加剧。自20世纪90年代中期以来，后一部分经历了显著的增长。我们使用卫星观测的冰川流速和区域气候模型相结合，以重建1958-2016年期间格陵兰冰盖和北极冰川和冰盖的陆地冰淡水通量。到2016年，累计淡水通量异常超过6，300 ± 316 km 3。这大约是之前一项分析的估计值的两倍，该分析不包括格陵兰岛以外的冰川和冰盖，并且只延续到2010年。从2010年起，总淡水通量约为1，300 km 3/yr，相当于0.04 Sv，约占同期北极总径流量的40%。并非所有这些通量都将到达深对流或北极和亚北极海域。然而，我们注意到，最大的淡水通量异常，按海盆分组，位于巴芬湾和戴维斯海峡。陆冰淡水通量表现出很强的季节性循环，夏季的数值通常是年平均值的5倍左右。这对于理解这些通量对峡湾环流、分层和海岸沃茨的地球化学和营养物质输送的影响是很重要的。淡水在巴芬湾已经积累了20年，淡水异常量已经达到6 300 km 3，是沿海水域不稳定营养物质的重要来源。
The freshwater budget of the Arctic and sub‐polar North Atlantic Oceans has been changing due, primarily, to increased river runoff, declining sea ice and enhanced melting of Arctic land ice. Since the mid‐1990s this latter component has experienced a pronounced increase. We use a combination of satellite observations of glacier flow speed and regional climate modeling to reconstruct the land ice freshwater flux from the Greenland ice sheet and Arctic glaciers and ice caps for the period 1958–2016. The cumulative freshwater flux anomaly exceeded 6,300 ± 316 km3 by 2016. This is roughly twice the estimate of a previous analysis that did not include glaciers and ice caps outside of Greenland and which extended only to 2010. From 2010 onward, the total freshwater flux is about 1,300 km3/yr, equivalent to 0.04 Sv, which is roughly 40% of the estimated total runoff to the Arctic for the same time period. Not all of this flux will reach areas of deep convection or Arctic and Sub‐Arctic seas. We note, however, that the largest freshwater flux anomalies, grouped by ocean basin, are located in Baffin Bay and Davis Strait. The land ice freshwater flux displays a strong seasonal cycle with summer time values typically around five times larger than the annual mean. This will be important for understanding the impact of these fluxes on fjord circulation, stratification, and the biogeochemistry of, and nutrient delivery to, coastal waters. Freshwater has been accumulating in Baffin Bay for 20 years The freshwater anomaly has reached 6,300 km3 Important source of labile nutrients to coastal water