Intrusion of warm Bering/Chukchi waters onto the shelf in the western Beaufort Sea
Intrusion of warm Bering/Chukchi waters onto the shelf in the western Beaufort Sea
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温暖的白令/楚科奇海水侵入波弗特海西部的陆架
DOI：
10.1029/2008jc004870
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发表时间：
2008
影响因子：
--
通讯作者：
R. Potter
中科院分区：
文献类型：
--
作者：
S. Okkonen;C. Ashjian;R. Campbell;W. Maslowski;Jaclyn L. Clement;R. Potter
根据2005-2007年8月中旬至9月中旬在阿拉斯加巴罗附近获得的高分辨率水文、声学多普勒海流剖面仪测量的海流和卫星测量的海面温度图像，描述了夏末阿拉斯加海岸流（ACC）带着温暖的白令海/楚科奇水域通过巴罗峡谷的路径上的风驱动变化。数值模拟用于为这些观测资料提供一个多年代际的背景。确定了四种广义的风况和相关的环流状态。当风向偏东或东南偏东时，ACC急流相对较强，沿巴罗峡谷南侧靠近陆架断裂。这些东风驱使大陆架内部洋流沿着阿拉斯加波弗特海岸向西北移动，在那里它们反对从巴罗峡谷向东侵入大陆架的温水。由于这些东风促使波弗特陆架上的海平面下降，并沿着波弗特斜坡上涌，ACC急流必然会变得更弱、更宽，并在离开巴罗峡谷时从波弗特陆架断裂向海移动。来自东北风促使ACC从巴罗峡谷的南侧分离，并沿着南侧形成一个峡谷上行流，部分由波弗特大陆架西部的水供给。当风弱或来自西南方向时，来自巴罗峡谷的温暖的白令海峡/楚科奇水域侵入波弗特西部大陆架。
[1] Wind-driven changes in the path of warm Bering/Chukchi waters carried by the Alaska Coastal Current (ACC) through Barrow Canyon during late summer are described from high-resolution hydrography, acoustic Doppler current profiler–measured currents, and satellite-measured sea surface temperature imagery acquired from mid-August to mid-September 2005–2007 near Barrow, Alaska. Numerical simulations are used to provide a multidecadal context for these observational data. Four generalized wind regimes and associated circulation states are identified. When winds are from the east or east-southeast, the ACC jet tends to be relatively strong and flows adjacent to the shelf break along the southern flank of Barrow Canyon. These easterly winds drive inner shelf currents northwestward along the Alaskan Beaufort coast where they oppose significant eastward intrusions of warm water from Barrow Canyon onto the shelf. Because these easterly winds promote sea level set down over the Beaufort shelf and upwelling along the Beaufort slope, the ACC jet necessarily becomes weaker, broader, and displaced seaward from the Beaufort shelf break upon exiting Barrow Canyon. Winds from the northeast promote separation of the ACC from the southern flank of Barrow Canyon and establish an up-canyon current along the southern flank that is fed in part by waters from the western Beaufort shelf. When winds are weak or from the southwest, warm Bering/Chukchi waters from Barrow Canyon intrude onto the western Beaufort shelf.