气候变化领域集成服务门户(CCPortal): Ventilation Pathways for the North Pacific Oxygen Deficient Zone

CCPortal

DOI	10.1029/2018GB006149
	Ventilation Pathways for the North Pacific Oxygen Deficient Zone
	Margolskee A.; Frenzel H.; Emerson S.; Deutsch C.
发表日期	2019
ISSN	0886-6236
EISSN	1944-9224
起始页码	875
结束页码	890
卷号	33 期号:7
英文摘要	Oxygen deficient zones (ODZs) in the tropical ocean exert a profound influence on global biogeochemical cycles, but the factors that regulate their long-term structure and sensitivity to oceanic change remain poorly understood. We analyzed hydrographic observations and a high-resolution physical/biogeochemical model to diagnose the primary pathways that ventilate the tropical Pacific ODZs. Historical and recent autonomous observations reveal pronounced and widespread O2 peaks, termed secondary oxygen maxima (SOMs), within the depths of the broader O2 minimum layer, especially at the equatorward edge of both northern and southern ODZs. In the northern ODZ, Lagrangian particle tracking in an eddy-permitting numerical model simulation attributes these features to intrusions of the Northern Subsurface Countercurrent along the equatorial edge of the ODZ. Zonal subsurface jets also ventilate the poleward edge of the northern ODZ but induce a smaller O2 flux and do not yield detectable SOMs. Along the ODZ's eastern boundary, oxygenation is achieved by the seasonal cycle of upwelling of low-O2 water onto the continental shelf, followed by downwelling of O2-replenished near-surface waters back into the ODZ. Waters entering the northern Pacific ODZ originate from the extratropics in both hemispheres, but two thirds are from the Southern Hemisphere and arrive later and with a wider range of transit times. These results suggest that predicting future changes in the large Pacific ODZs will require a better understanding of the climate sensitivity of the narrow zonal jets and seasonal dynamics of coastal upwelling that supply their O2. ©2019. The Authors.
英文关键词	oxygen deficient zone; Regional Ocean Modeling System; secondary oxygen maxima; ventilation
语种	英语
scopus关键词	biogeochemical cycle; countercurrent; deep water ventilation; extratropical environment; hydrographic survey; jet flow; Lagrangian analysis; numerical model; oxygen; oxygen minimum layer; regional climate; Southern Hemisphere; tropical environment; upwelling; zonal flow; Pacific Ocean; Pacific Ocean (North)
来源期刊	Global Biogeochemical Cycles
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/129751
作者单位	School of Oceanography, University of Washington, Seattle, WA, United States; Department of Biology, University of Washington, Seattle, WA, United States
推荐引用方式 GB/T 7714	Margolskee A.,Frenzel H.,Emerson S.,et al. Ventilation Pathways for the North Pacific Oxygen Deficient Zone[J],2019,33(7).
APA	Margolskee A.,Frenzel H.,Emerson S.,&Deutsch C..(2019).Ventilation Pathways for the North Pacific Oxygen Deficient Zone.Global Biogeochemical Cycles,33(7).
MLA	Margolskee A.,et al."Ventilation Pathways for the North Pacific Oxygen Deficient Zone".Global Biogeochemical Cycles 33.7(2019).