Freshwater composition of the waters off southeast Greenland and their link to the Arctic Ocean
Freshwater composition of the waters off southeast Greenland and their link to the Arctic Ocean
复制标题
格陵兰岛东南部海域的淡水组成及其与北冰洋的联系
DOI：
10.1029/2008jc004808
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发表时间：
2009
影响因子：
--
通讯作者：
J. Ólafsson
中科院分区：
文献类型：
--
作者：
D. Sutherland;R. Pickart;E. Jones;K. Azetsu;A. J. Eert;J. Ólafsson
[1]淡水组成的沃茨的东南格陵兰陆架和斜坡上使用一组高分辨率的断面占领2004年夏天，其中包括水文，流速，营养和化学示踪测量。营养盐和示踪剂数据被用来量化的太平洋水，海冰融化，大气降水存在于东格陵兰电流（EGC）和东格陵兰沿岸流（EGCC）的上层的分数。EGC/EGCC系统主导了该地区的环流，并强烈影响了观测到的三种淡水类型的分布。海冰融化和大气降水量在海面上增强，反映了它们的来源，并且从丹麦海峡到Cape Farewell向南以及向滨增加。在EGCC的次表层中发现了相当大一部分太平洋水，这支持了这样一种观点，即这个内大陆架分支直接与EGC相连，从而与北冰洋相连。利用一组历史断面，研究了1984 - 2004年丹麦海峡附近EGC和EGCC中太平洋水含量的变化。1990年代后期，太平洋水的比例大幅增加，随后在2002年和2004年降至较低水平，反映了先前报告的弗拉姆海峡太平洋水含量的减少。这种变化被发现与北极涛动指数，滞后了9年，表明北冰洋环流模式带来了不同量的太平洋水通过EGC/EGCC北大西洋显着相关。
[1] The freshwater composition of waters on the southeast Greenland shelf and slope are described using a set of high-resolution transects occupied in summer 2004, which included hydrographic, velocity, nutrient, and chemical tracer measurements. The nutrient and tracer data are used to quantify the fractions of Pacific Water, sea ice melt, and meteoric water present in the upper layers of the East Greenland Current (EGC) and East Greenland Coastal Current (EGCC). The EGC/EGCC system dominates the circulation of this region and strongly influences the observed distribution of the three freshwater types. Sea ice melt and meteoric water fractions are surface intensified, reflecting their sources, and generally increase southward from Denmark Strait to Cape Farewell, as well as shoreward. Significant fractions of Pacific Water are found in the subsurface layers of the EGCC, supporting the idea that this inner shelf branch is directly linked to the EGC and thus to the Arctic Ocean. A set of historical sections is examined to investigate the variability of Pacific Water content in the EGC and EGCC from 1984 to 2004 in the vicinity of Denmark Strait. The fraction of Pacific Water increased substantially in the late 1990s and subsequently declined to low levels in 2002 and 2004, mirroring the reduction in Pacific Water content reported previously at Fram Strait. This variability is found to correlate significantly with the Arctic Oscillation index, lagged by 9 years, suggesting that the Arctic Ocean circulation patterns bring varying amounts of Pacific Water to the North Atlantic via the EGC/EGCC.