气候变化领域集成服务门户(CCPortal): Deep Eddy Kinetic Energy in the Tropical Pacific From Lagrangian Floats

CCPortal

DOI	10.1029/2020JC016313
	Deep Eddy Kinetic Energy in the Tropical Pacific From Lagrangian Floats
	Delpech A.; Cravatte S.; Marin F.; Ménesguen C.; Morel Y.
发表日期	2020
ISSN	21699275
卷号	125 期号:8
英文摘要	At the ocean surface, satellite observations have shown evidence of a large spectrum of waves at low latitudes. However, very little is known about the existence and properties of the deep variability. Most of the subsurface observations rely on localized measurements, which do not allow for a global estimation of this variability. In this study, we use velocity estimates, provided by Argo float drifts at 1,000 m, to analyze the spatial and temporal distribution of the deep eddy kinetic energy (EKE) and its spectral signature with an unprecedented time and space coverage. In the tropical Pacific, high EKE is found along the equator, at the western boundary and poleward of 7°N. EKE meridional distribution is also found to vary at the scale of the meridionally alternating mean zonal jets: it is higher inside eastward currents. We develop an original statistical scale analysis to determine the temporal and spatial scale dependence of this deep EKE footprint. We show the presence of periodic features whose characteristics are compatible with theoretical equatorial waves dispersion relations. Annual and semiannual Rossby waves are observed at the equator, as well as ∼30-day Yanai waves, consistent with surface tropical instability waves. The location and intensification of these waves match the downward energy propagation predicted by ray tracing linear theory. Short-scale variability (with ∼70-day periods and 500-km wavelength) has also been detected poleward of 7°N. The generation mechanisms of this variability are discussed, as well as its potential importance for the mean circulation. © 2020. American Geophysical Union. All Rights Reserved.
英文关键词	Argo floats; deep ocean; eddy kinetic energy; equatorial and tropical ocean; equatorial waves
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/186738
作者单位	LEGOS (Laboratoire d'Etudes en Géophysique et Océanographie Spatiales), Université de Toulouse, CNES, CNRS, IRD, Toulouse, France; LOPS (Laboratoire d'Océanographie Physique et Spatiale), Université de Bretagne Occidentale, Ifremer, CNRS, IRD, Brest, France
推荐引用方式 GB/T 7714	Delpech A.,Cravatte S.,Marin F.,et al. Deep Eddy Kinetic Energy in the Tropical Pacific From Lagrangian Floats[J],2020,125(8).
APA	Delpech A.,Cravatte S.,Marin F.,Ménesguen C.,&Morel Y..(2020).Deep Eddy Kinetic Energy in the Tropical Pacific From Lagrangian Floats.Journal of Geophysical Research: Oceans,125(8).
MLA	Delpech A.,et al."Deep Eddy Kinetic Energy in the Tropical Pacific From Lagrangian Floats".Journal of Geophysical Research: Oceans 125.8(2020).