A quick response of the equatorial ocean to Antarctic sea ice/salinity anomalies
A quick response of the equatorial ocean to Antarctic sea ice/salinity anomalies
复制标题
赤道海洋对南极海冰/盐度异常的快速响应
DOI：
10.1029/2005jc003061
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发表时间：
2006
影响因子：
--
通讯作者：
J. Schröter
中科院分区：
文献类型：
--
作者：
V. Ivchenko;V. Zalesny;M. Drinkwater;J. Schröter
赤道海洋对高纬度南大洋发生的过程作出快速反应的潜在机制已得到研究。在德雷克海峡纬度的南大洋，有一个纬向无界的“通道”，即南极绕极流带（ACCB）。研究表明，在像ACCB这样的多连通区域，南大洋海冰覆盖/盐度分布异常产生的信号能够以快速移动的正压罗斯贝波的形式以波状方式传播。研究表明，在德雷克海峡附近引发的扰动会产生一个罗斯贝波，该波仅在几天内就能横穿太平洋。这个信号在太平洋西边界反射，并产生一个向赤道传播的沿岸被困开尔文波。由此产生的温度异常沿着西部海岸线向北移动，直至赤道附近，并且其振幅随时间增加。赤道太平洋西部边缘的异常随后开始作为一个被困赤道波沿着赤道向东传播。大约2 - 3个月后，该波到达东海岸，反射并产生沿岸被困波，该波沿着两个半球的海岸线向北和向南传播。这一过程被认为是温带海洋能够在赤道海洋中引发异常的一种可能的直接机制。
The potential mechanisms for a quick response of the equatorial ocean to processes occurring in the high-latitude Southern Ocean have been investigated. In the Southern Ocean at the Drake Passage latitudes, there is an zonally unbounded “channel”, the Antarctic Circumpolar Current Belt (ACCB). It is demonstrated that in a multiconnected domain such as the ACCB, signals generated by anomalies in the Southern Ocean sea ice cover/salinity distribution can propagate in a wave-like manner in the form of fast moving barotropic Rossby waves. A disturbance induced near the Drake Passage is demonstrated to generate a Rossby wave that propagates across the Pacific in only a few days. This signal is reflected at the western boundary of the Pacific and generates an equatorward propagating coastally trapped Kelvin wave. The resulting temperature anomaly moves northward along the western coastline up to the vicinity of the equator and increases in amplitude over time. The anomaly in the western edge of equatorial Pacific then begins to propagate eastward along the equator as a trapped equatorial wave. After about 2–3 months this wave reaches the eastern coast, reflects, and generates the coastal trapped wave, which propagates north and south along the coastline in both hemispheres. This process is suggested as one possible direct mechanism by which the extratropical ocean can induce anomalies in the equatorial ocean.