气候变化领域集成服务门户(CCPortal): Multidecadal to decadal variability in the equatorial Indian Ocean subsurface temperature and the forcing mechanisms

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DOI	10.1007/s00382-020-05185-7
	Multidecadal to decadal variability in the equatorial Indian Ocean subsurface temperature and the forcing mechanisms
	Mohapatra S.; Gnanaseelan C.; Deepa J.S.
发表日期	2020
ISSN	0930-7575
起始页码	3475
结束页码	3487
卷号	54
英文摘要	The Tropical Indian Ocean (TIO) is seen to exhibit robust warming after the 1950s. Most of the previous studies on the Indian Ocean (IO) surface and subsurface temperature focussed on long-term trends and interannual variability. The multidecadal to decadal variability in the Eastern Equatorial Indian Ocean (EEIO, 80°E–110°E, 8°S–5°N, 50-110 m) subsurface temperature is studied using reanalysis products and ocean general circulation model (OGCM) simulations. Prior to 1990s, the EEIO subsurface temperature is found to be dominated mostly by the multidecadal variability. However, since the mid-1990s, significant decadal variability is observed, something that has not been reported before. The mechanisms responsible for the observed decadal and multidecadal variability in the EEIO subsurface temperature are studied in detail. Wind forcing along the equator, and the associated ocean dynamics are found to be the major factors responsible for the EEIO subsurface temperature variability in the decadal and multidecadal time scales, emphasizing the importance of local atmospheric forcing on this variability. Alongshore winds along the Sumatra coast also contribute considerably to the decadal changes in the EEIO subsurface temperature. It is also found that the observed decadal and multidecadal changes are independent of the phase reversal of Interdecadal pacific oscillation (IPO). OGCM sensitivity experiments also suggest that the decadal variability of EEIO subsurface temperature is largely unaffected by the oceanic pathways such as Indonesian Through Flow (ITF). Hence, remote forcing through these pathways is insignificant in the TIO subsurface temperature north of 10°S as compared to the TIO wind forcing. Consistent with EEIO subsurface temperature, equatorial IO (EIO) winds also exhibit decadal variability post mid-1990s. The major contributors for the decadal variability in EIO winds are found to be the decadal variability in the Mascarene high, the low level jet, and the large scale off-equatorial circulations. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Decadal variability; Eastern equatorial Indian Ocean; Interdecadal pacific oscillation; Mascarene high; Subsurface temperature
语种	英语
scopus关键词	annual variation; atmospheric dynamics; decadal variation; general circulation model; jet; surface temperature; wind forcing; Indian Ocean
来源期刊	Climate Dynamics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/145521
作者单位	Indian Institute of Tropical Meteorology, Pune, 411008, India; Savitribai Phule Pune University, Pune, 411007, India
推荐引用方式 GB/T 7714	Mohapatra S.,Gnanaseelan C.,Deepa J.S.. Multidecadal to decadal variability in the equatorial Indian Ocean subsurface temperature and the forcing mechanisms[J],2020,54.
APA	Mohapatra S.,Gnanaseelan C.,&Deepa J.S..(2020).Multidecadal to decadal variability in the equatorial Indian Ocean subsurface temperature and the forcing mechanisms.Climate Dynamics,54.
MLA	Mohapatra S.,et al."Multidecadal to decadal variability in the equatorial Indian Ocean subsurface temperature and the forcing mechanisms".Climate Dynamics 54(2020).