Winter Water Formation in Coastal Polynyas of the Eastern Chukchi Shelf: Pacific and Atlantic Influences
Winter Water Formation in Coastal Polynyas of the Eastern Chukchi Shelf: Pacific and Atlantic Influences
复制标题
DOI：
10.1029/2017jc013307
复制
发表时间：
2018-08-01
影响因子：
3.6
通讯作者：
Tamura, Takeshi
中科院分区：
文献类型：
--
作者：
Hirano, Daisuke;Fukamachi, Yasushi;Tamura, Takeshi
利用来自系泊、大气再分析、卫星衍生的海冰生成 (SIP) 和数值示踪剂实验的数据，对阿拉斯加海岸楚科奇大陆架东部（即所谓的巴罗峡谷通道）的阿拉斯加沿海冬季水 (ACWW) 的水特性和形成过程进行了检查。沿着这条路径，太平洋冬季水（PWW）可以通过 SIP 进行改造以生产 ACWW，同时在沿海冰间湖中生产冷的咸水间湖水，温暖的大西洋水（AW）上涌，并在陆架上进行混合过程。形成了三种不同类型的 ACWW：(i) AW 和 PWW 的混合物，(ii) AW 和冰间湖水的混合物，以及 (iii) 高盐冰间湖水。东北风与波弗特高压和阿留申低压之间的南北气压梯度相关，是巴罗沿海冰间湖 (BCP) 冰间湖 SIP 事件和 AW 上升流的常见触发因素。由于东北风的双重影响，BCP 中的 PWW 修改过程比楚科奇冰间湖其他地方发生的更为复杂。 AW 上升流对 ACWW 形成的影响在 BCP 中最为突出，通常集中在沿海地区。所有类型的 ACWW 基本上都随着楚科奇斜坡流和/或波弗特环流向西或西北输送，最终有助于维持低盐斜层，特别是在楚科奇边境、北风山脊和加拿大盆地南部。即使在北冰洋的太平洋部分，ACWW 特性也受到大西洋起源和太平洋起源水域的强烈影响。
Water properties and formation processes of Alaskan Coastal Winter Water (ACWW) over the eastern Chukchi shelf along the Alaska coast, the so-called Barrow Canyon pathway, are examined using data from moorings, atmospheric reanalysis, satellite-derived sea-ice production (SIP), and a numerical tracer experiment. Along this pathway, Pacific Winter Water (PWW) can be modified to produce ACWW through SIP accompanied by production of cold, saline polynya water in the coastal polynyas, upwelling of warm Atlantic Water (AW), and mixing processes on the shelf. Three different types of ACWW are formed: (i) a mixture of AW and PWW, (ii) a mixture of AW and polynya water, and (iii) hypersaline polynya water. The northeasterly winds, correlated with the north-south atmospheric pressure gradient between Beaufort High and Aleutian Low, are common triggers of polynya SIP episodes and AW upwelling in the Barrow Coastal Polynya (BCP). Due to the dual impact of northeasterly winds, PWW modification processes in the BCP are more complicated than what occurs elsewhere in the Chukchi Polynya. The impact of AW upwelling on the ACWW formation is most prominent in the BCP, usually centered along the coast. All types of ACWW are thought to be basically transported westward or northwestward with the Chukchi slope current and/or Beaufort Gyre and finally contribute to maintenance of the lower halocline layer especially over the Chukchi Borderland, Northwind Ridge, and southern Canada Basin. Even in the Pacific sector of the Arctic Ocean, ACWW properties are strongly influenced by both Atlantic-origin and Pacific-origin waters.