气候变化领域集成服务门户(CCPortal): Tropical cyclone landfalls south of the Tropic of Capricorn; southwest Indian Ocean

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DOI	10.3354/cr01575
	Tropical cyclone landfalls south of the Tropic of Capricorn; southwest Indian Ocean
	Pillay M.T.; Fitchett J.M.
发表日期	2019
ISSN	0936-577X
起始页码	23
结束页码	37
卷号	79 期号:1
英文摘要	Common perception holds that tropical cyclones occur exclusively within the latitudinal range of 5° to 20° S. However, a few storms have been recorded poleward of this range each decade over the past half century. This study explores tropical cyclone occurrence south of the Tropic of Capricorn in the southwest Indian Ocean (SWIO; defined as 0°-30° S; African East coast up to 110° E). Using observational tropical cyclone and climate data, the small subset of storms making landfall in the region were examined in detail. The records indicate a decrease in storm frequency, while intensity has increased over the study period (1950-2015). Sea surface temperature (SST) reveals the interaction and influence of surface thermodynamics on tropical cyclone trajectory. Zonal wind at the 500 mb level indicates a modulation on track morphology following genesis, and may be responsible for recurving tracks. A decadal variability is observed for landfall location, which is currently in a low-amplitude southward component. SST is significantly related to storm intensity, while the Dipole Mean Index (DMI) and Southern Annular Mode (SAM) are related to and coincide with the highest landfall years. The Multivariate El Niño Southern Oscillation Index (MEI) is related to recurving track trajectories, while DMI and SAM may influence latitudinal and longitudinal track trajectories. These findings are important in understanding recent changes in tropical cyclone dynamics in the southwest Indian Ocean, particularly as the range of storm occurrence has expanded under climate warming. © Inter-Research 2019.
英文关键词	Climate variability; Climatology; Southwest Indian Ocean; Tropic of Capricorn; Tropical cyclone
语种	英语
scopus关键词	climatology; decadal variation; El Nino-Southern Oscillation; frequency analysis; multivariate analysis; perception; sea surface temperature; storm track; thermodynamics; tropical cyclone; zonal wind; Indian Ocean
来源期刊	Climate Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146918
作者单位	School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, 2050, South Africa
推荐引用方式 GB/T 7714	Pillay M.T.,Fitchett J.M.. Tropical cyclone landfalls south of the Tropic of Capricorn; southwest Indian Ocean[J],2019,79(1).
APA	Pillay M.T.,&Fitchett J.M..(2019).Tropical cyclone landfalls south of the Tropic of Capricorn; southwest Indian Ocean.Climate Research,79(1).
MLA	Pillay M.T.,et al."Tropical cyclone landfalls south of the Tropic of Capricorn; southwest Indian Ocean".Climate Research 79.1(2019).