Near-surface recirculation over Georges Bank
Near-surface recirculation over Georges Bank
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DOI：
10.1016/s0967-0645(96)00052-5
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发表时间：
1996-01-01
影响因子：
3
通讯作者：
Beardsley, RC
中科院分区：
文献类型：
--
作者：
Limeburner, R;Beardsley, RC
1988年冬末和1989年春，在缅因州湾西部的大南海峡北方发射了卫星跟踪的漂流器，其中心位于近地表（5 m）和季节性温跃层（50 m）以下，以调查作为南海峡海洋生产力试验（SCOPEX）一部分的区域环流。许多近地表的漂流物被夹带在乔治银行的顺时针环流中，在分层季节，有8个漂流物在银行周围总共绕了16圈。这8条漂流物的平均回流周期为48 d，平均绕岸流速为12 cm s（-1）。漂流物资料中没有明确的证据表明，在分层季节，岸边顺时针环流的强度随时间而增加。平均而言，这些漂流物（i）沿着一条相对狭窄的路径围绕银行，除了在银行的东端，在那里观察到三条首选路径，（ii）在银行的北方和南方汉克移动最快，（iii）没有进入3500 km（2）的核心区域，中心位于北纬41度17 '，西经68度00'，在河岸地形中心西南约30 lan处，（iv）在11月底停止环绕河岸，部分原因是强风事件似乎将漂流者赶出了河岸。奇怪的是，没有一个近地表的漂流物从乔治浅滩的南翼移动到新英格兰大陆架上，这可能是因为气流沿着外大陆架的连续性;相反，环绕浅滩的漂流物倾向于沿着沿着南岸离开浅滩。没有一个中心在50米处装有锥管的漂流物似乎在乔治浅滩周围重新循环。版权所有（C）1996 Elsevier Science Ltd.
Satellite-tracked drifters with drogues centered near-surface (5 m) and below the seasonal thermocline (50 m) were launched during late winter and spring of 1988 and 1989 in the northern Great South Channel in the western Gulf of Maine to investigate the regional circulation as part of the South Channel Ocean Productivity Experiment (SCOPEX). Many of the near-surface drifters became entrained in the clockwise gyre over Georges Bank, and eight drifters made a total of 16 complete circuits around the bank during the stratified season. The average recirculation period of these eight drifters was 48 days, and the average drifter speed around the bank was 12 cm s(-1). There is no clear evidence from the drifter data that the strength of the clockwise gyre over the bank increased with time during the stratified season. On average, these drifters (i) followed a relatively narrow path around the bank, except over the eastern end of the bank where three preferred paths were observed, (ii) moved fastest over the northern and southern hanks of the bank, (iii) did not enter a core area of 3500 km(2) centered at 41 degrees 17'N, 68 degrees 00'W, approximately 30 lan southwest of the topographic center of the bank, and (iv) stopped circling the bank by the end of November, due in part to strong wind events that appeared to drive drifters off the bank. Curiously, none of the near-surface drifters moved from the southern flank of Georges Bank onto the New England shelf as might be expected from continuity of flow along the outer shelf; instead, the drifters that circled the bank tended to move off the bank along its southern hank. None of the drifters with drogues centered at 50 m appeared to recirculate around Georges Bank. Copyright (C) 1996 Elsevier Science Ltd.