The Role of Topographically Induced Vortices in Tropical Cyclone Formation over the Indian Ocean
The Role of Topographically Induced Vortices in Tropical Cyclone Formation over the Indian Ocean
复制标题
地形引起的涡旋在印度洋热带气旋形成中的作用
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
Richard K. Taft
中科院分区：
文献类型：
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作者：
Caitlin M. Fine;Richard H. Johnson;P. Ciesielski;Richard K. Taft
摘要本文研究了苏门答腊及其附近地形特征在印度洋热带气旋形成过程中的作用。苏门答腊岛、马来半岛和爪哇都有多山的地形，在典型的环境分层下，这些地形部分阻挡了低层水流。对于偏东的低空气流，这些地形特征经常产生背风涡，其中一些随后从苏门答腊岛的南北端脱落并向西移动，然后向下游越过印度洋。由于苏门答腊横跨赤道，从大约6°N向6°S向西北-东南方向延伸，背风涡旋虽然反向旋转，但都是气旋性的。因此，它们可以作为初始扰动，最终有助于在IO上形成TC。此外，撞击苏门答腊岛的低空、赤道西风气流通常也会被阻挡和发散，有时会在印度洋上空形成气旋环流，主要是在该岛的南端附近。数据来自最近的两个…
AbstractThe role of Sumatra and adjacent topographic features in tropical cyclone (TC) formation over the Indian Ocean (IO) is investigated. Sumatra, as well as the Malay Peninsula and Java, have mountainous terrain that partially blocks low-level flow under typical environmental stratification. For easterly low-level flow, these terrain features often produce lee vortices, some of which subsequently shed and move westward from the northern and southern tips of Sumatra and thence downstream over the IO. Since Sumatra straddles the equator, extending in a northwest–southeast direction from approximately 6°N to 6°S, the lee vortices, while counter-rotating, are both cyclonic. Hence, they can serve as initial disturbances that eventually contribute to TC formation over the IO. In addition, low-level, equatorial westerly flow impinging on Sumatra is also typically blocked and diverges, at times contributing to cyclonic circulations over the IO, primarily near the southern end of the island.Data from two recen...