气候变化领域集成服务门户(CCPortal): Back-to-Back Occurrence of Tropical Cyclones in the Arabian Sea During October

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DOI	10.1029/2019JC015836
	Back-to-Back Occurrence of Tropical Cyclones in the Arabian Sea During October–November 2015: Causes and Responses
	Roy Chowdhury R.; Prasanna Kumar S.; Narvekar J.; Chakraborty A.
发表日期	2020
ISSN	21699275
卷号	125 期号:6
英文摘要	In the Arabian Sea, two extremely severe cyclonic storms occurred back to back during October–November 2015. Using a suite of ocean and atmospheric data, we examined the upper ocean responses of tropical cyclones Chapala and Megh, the latter originated immediately after the dissipation of the former. Cyclones Chapala and Megh cooled the sea surface by 1.5°C and 1.0°C, respectively, which was also captured by Bio-Argo float in the vicinity of their tracks. The cyclone-induced chlorophyll a enhancement was 6 and 2 times respectively from their precyclone value of 0.36 and 0.30 mg/m3, while the net primary productivity showed an increase of 5.8 and 1.7 times respectively from the precyclone values of 496.26 and 518.63 mg C/m2/day after the passage of Chapala and Megh. The CO2 flux showed a sixfold and twofold increase respectively compared to the precyclone value of 2.69–3.58 and 6.78 mmol/m2/day. We show that the anomalous co-occurrence of the positive phase of Indian Ocean Dipole and the strong El Niño supported large-scale warming in the western Arabian Sea. Subsequent altered Walker circulation played a decisive role in the preconditioning of both atmosphere and ocean, which led to a situation congenial for cyclogenesis. What triggered the formation of the cyclone Chapala was the arrival of eastward-propagating atmospheric convection associated with the Madden-Julian oscillation. The generation of the second cyclone Megh within 8 days appears to be associated with the oceanic Rossby wave that led to an increase in the upper ocean heat content by deepening the 26°C isotherm in the vicinity of the origin of cyclones. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	CO2 outgassing; Indian Ocean Dipole; Madden-Julian oscillation; Net primary productivity; Rossby wave; SST cooling
语种	英语
来源期刊	Journal of Geophysical Research: Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/186845
作者单位	Centre for Oceans, Rivers, Atmosphere and Land Sciences, Indian Institute of Technology Kharagpur, Kharagpur, India; CSIR—National Institute of Oceanography, Dona Paula, Goa, India
推荐引用方式 GB/T 7714	Roy Chowdhury R.,Prasanna Kumar S.,Narvekar J.,等. Back-to-Back Occurrence of Tropical Cyclones in the Arabian Sea During October–November 2015: Causes and Responses[J],2020,125(6).
APA	Roy Chowdhury R.,Prasanna Kumar S.,Narvekar J.,&Chakraborty A..(2020).Back-to-Back Occurrence of Tropical Cyclones in the Arabian Sea During October–November 2015: Causes and Responses.Journal of Geophysical Research: Oceans,125(6).
MLA	Roy Chowdhury R.,et al."Back-to-Back Occurrence of Tropical Cyclones in the Arabian Sea During October–November 2015: Causes and Responses".Journal of Geophysical Research: Oceans 125.6(2020).