气候变化领域集成服务门户(CCPortal): Rectified Effects of Interannual Chlorophyll Variability on the Tropical Pacific Climate Revealed by a Hybrid Coupled Physics-Biology Model

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DOI	10.1029/2021JC017263
	Rectified Effects of Interannual Chlorophyll Variability on the Tropical Pacific Climate Revealed by a Hybrid Coupled Physics-Biology Model
	Tian F.; Zhang R.-H.; Wang X.; Zhi H.
发表日期	2021
ISSN	21699275
卷号	126 期号:6
英文摘要	El Niño-Southern Oscillation (ENSO) induces large interannual chlorophyll variability (ICV) in the tropical Pacific, which modulates shortwave penetration in the upper ocean. However, the extent to which ICV can have rectified effect (higher-frequency process impacts low-frequency climate variability (i.e., ENSO) and mean state) in the tropical Pacific remains unclear. Here, a hybrid coupled physics-biogeochemistry model with tunable coupling ocean-atmosphere intensity (α) is used to examine this rectified effect. The simulations consist of a control run in which the ICV effect is represented in the model and the other with the ICV effect being purposely excluded by only reserving the climatological chlorophyll field. Results show that the ICV effect depends on α; ENSO amplitude is reduced by 12%–40% with decreased annual mean sea surface temperature by 0.05–0.4°C in the eastern equatorial Pacific when taking α = 0.8–1.15. A stability analysis reveals that the ICV effect on ENSO exhibits two feedback loops. (a) Positive (negative) chlorophyll anomalies during La Niña (El Niño) act to increase (decrease) shortwave absorption within the mixed layer, which enhances thermodynamic damping (slightly weakening ENSO amplitude). (b) Chlorophyll anomalies modulate vertical redistribution of penetrative shortwave radiation between the mixed layer and subsurface layers; this differential heating affects ocean stratification and vertical mixing, which weakens the thermocline and Ekman feedback (predominantly weakening ENSO amplitude). Additionally, ICV exhibits asymmetric effects on ENSO evolution, with the El Niño amplitude being damped stronger than La Nina; this residual effect leads to a net cooling condition in the eastern tropical Pacific. © 2021. American Geophysical Union. All Rights Reserved.
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/186268
作者单位	Key Laboratory of Ocean Circulation and Waves, Institute of Oceanology, and Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China; Laboratory for Ocean and Climate Dynamics, Pilot National Laboratory for Marine Science and Technology, Qingdao, China; University of Chinese Academy of Sciences, Beijing, China; Center for Excellence in Quaternary Science and Global Change, Chinese Academy of Sciences, Xi’an, China; College of Global Change and Earth System Science, Beijing Normal University, Beijing, China; College of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, China
推荐引用方式 GB/T 7714	Tian F.,Zhang R.-H.,Wang X.,et al. Rectified Effects of Interannual Chlorophyll Variability on the Tropical Pacific Climate Revealed by a Hybrid Coupled Physics-Biology Model[J],2021,126(6).
APA	Tian F.,Zhang R.-H.,Wang X.,&Zhi H..(2021).Rectified Effects of Interannual Chlorophyll Variability on the Tropical Pacific Climate Revealed by a Hybrid Coupled Physics-Biology Model.Journal of Geophysical Research: Oceans,126(6).
MLA	Tian F.,et al."Rectified Effects of Interannual Chlorophyll Variability on the Tropical Pacific Climate Revealed by a Hybrid Coupled Physics-Biology Model".Journal of Geophysical Research: Oceans 126.6(2021).