气候变化领域集成服务门户(CCPortal): Subtropical-tropical pathways of spiciness anomalies and their impact on equatorial Pacific temperature

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DOI	10.1007/s00382-020-05524-8
	Subtropical-tropical pathways of spiciness anomalies and their impact on equatorial Pacific temperature
	Zeller M.; McGregor S.; van Sebille E.; Capotondi A.; Spence P.
发表日期	2021
ISSN	0930-7575
卷号	56 期号:2021-03-04
英文摘要	Understanding mechanisms of tropical Pacific decadal variability (TPDV) is of high importance for differentiating between natural climate variability and human induced climate change as this region sustains strong global teleconnections. Here, we use an ocean general circulation model along with a Lagrangian tracer simulator to investigate the advection of density compensated temperature anomalies (“spiciness mechanism”) as a potential contributor to TPDV during the 1980–2016 period. Consistent with observations, we find the primary regions of spiciness generation in the eastern subtropics of each hemisphere. Our results indicate that 75% of the equatorial subsurface water originates in the subtropics, of which two thirds come from the Southern hemisphere. We further show two prominent cases where remotely generated spiciness anomalies are advected to the equatorial Pacific, impacting subsurface temperature. The relative contribution of Northern versus Southern Hemisphere prominence and/or interior versus western boundary pathways depends on the specific event. The anomalously warm case largely results from advection via the Southern hemisphere interior (65%), while the anomalously cold case largely results from advection via the Northern hemisphere western boundary (48%). The relatively slow travel times from the subtropics to the equator (> 4 years) suggests that these spiciness anomalies underpin a potentially predictable contribution to TPDV. However, not all decadal peaks in equatorial spiciness can be explained by remotely generated spiciness anomalies. In those cases, we propose that spiciness anomalies are generated in the equatorial zone through changes in the proportion of Northern/Southern hemisphere source waters due to their different mean spiciness distribution. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
英文关键词	Decadal variability; Ocean spiciness; Tropical Pacific
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/183400
作者单位	School of Earth, Atmosphere and Environment, Monash University, Melbourne, Australia; GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany; Institute for Marine and Atmospheric Research, Utrecht University, Utrecht, Netherlands; Physical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, United States; School of Geosciences, University of Sydney, Sydney, Australia
推荐引用方式 GB/T 7714	Zeller M.,McGregor S.,van Sebille E.,et al. Subtropical-tropical pathways of spiciness anomalies and their impact on equatorial Pacific temperature[J],2021,56(2021-03-04).
APA	Zeller M.,McGregor S.,van Sebille E.,Capotondi A.,&Spence P..(2021).Subtropical-tropical pathways of spiciness anomalies and their impact on equatorial Pacific temperature.Climate Dynamics,56(2021-03-04).
MLA	Zeller M.,et al."Subtropical-tropical pathways of spiciness anomalies and their impact on equatorial Pacific temperature".Climate Dynamics 56.2021-03-04(2021).