...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Physical Oceanography >On Sverdrup Discontinuities and Vortices in the Southwest Indian Ocean
【24h】

On Sverdrup Discontinuities and Vortices in the Southwest Indian Ocean

机译：关于西南印度洋的白ver间断和涡旋

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The southwest Indian Ocean is distinguished by discontinuities in the wind-driven Sverdrup circulation. These connect the northern and southern tips of Madagascar with Africa and the southern tip of Africa with South America. In an analytical barotropic model with a flat bottom, the discontinuities produce intense westward jets. Those off the northern tip of Madagascar and the southern tip of Africa are always present, while the strength of that off southern Madagascar depends on the position of the zero curl line in the Indian Ocean (the jet is strong if the line intersects Madagascar but weak if the line is north of the island). All three jets are barotropically unstable by the Rayleigh-Kuo criterion. The authors studied the development of the instability using a primitive equation model, with a flat bottom and realistic coastlines. The model produced westward jets at the three sites and these became unstable after several weeks, generating 200-300-km scale eddies. The eddies generated west of Madagascar are in accord with observations and with previous numerical studies. The model's Agulhas eddies are similar in size to the observed eddies, both the anticy-clonic rings and the cyclones that form to the west of the tip of South Africa. However, the model's Agulhas does not retroflect, most likely because of its lack of stratification and topography, and so cannot capture pinching-off events. It is noteworthy nevertheless that a retroflection is not required to produce eddies here.
机译：西南印度洋的特点是风力驱动的Sverdrup循环不连续。这些将马达加斯加的北端和南端与非洲相连，将非洲的南端与南美相连。在具有平坦底部的解析正压模型中，间断点产生强烈的向西射流。马达加斯加北端和非洲南端始终存在，而马达加斯加南部的强度取决于印度洋零卷曲线的位置（如果该线与马达加斯加相交，则射流较强，但较弱如果线在岛的北部）。根据瑞利-考标准，这三个喷流都处于正压不稳定状态。作者使用具有平坦底部和逼真的海岸线的原始方程模型研究了不稳定性的发展。该模型在三个地点产生了向西的喷射流，几周后变得不稳定，产生了200-300公里的涡流。马达加斯加以西产生的涡流与观测值和先前的数值研究一致。该模型的Agulhas涡流的大小与观察到的涡流相似，包括反周期阵圈和形成于南非尖端西侧的旋风。但是，该模型的Agulhas不会后退，这很可能是因为它缺乏分层和地形，因此无法捕获挤压事件。但是，值得注意的是，此处不需要涡旋来产生涡流。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号