The Influence of the Madden–Julian Oscillation on Tropical Cyclone Activity in the Fiji Region
The Influence of the Madden–Julian Oscillation on Tropical Cyclone Activity in the Fiji Region
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DOI：
10.1175/2009jcli3316.1
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发表时间：
2010-02
影响因子：
4.9
通讯作者：
S. Chand;K. Walsh
中科院分区：
文献类型：
--
作者：
S. Chand;K. Walsh
Abstract This study examines the modulation of tropical cyclone (TC) activity by the Madden–Julian oscillation (MJO) in the Fiji, Samoa, and Tonga regions (FST region), using Joint Typhoon Warning Center best-track cyclone data and the MJO index developed by Wheeler and Hendon. Results suggest strong MJO–TC relationships in the FST region. The TC genesis patterns are significantly altered over the FST region with approximately 5 times more cyclones forming in the active phase than in the inactive phase of the MJO. This modulation is further strengthened during El Nino periods. The large-scale environmental conditions (i.e., low-level relative vorticity, upper-level divergence, and vertical wind shear) associated with TC genesis show a distinct patterns of variability for the active and inactive MJO phases. The MJO also has a significant effect on hurricane category and combined gale and storm category cyclones in the FST region. The occurrences of both these cyclone categories are increased in the active ...
