DOI: 10.1002/2017GB005829
论文题名: Oxygen Saturation Surrounding Deep Water Formation Events in the Labrador Sea From Argo-O2 Data
作者: Wolf M.K. ; Hamme R.C. ; Gilbert D. ; Yashayaev I. ; Thierry V.
刊名: Global Biogeochemical Cycles
ISSN: 0886-6236
EISSN: 1944-9224
出版年: 2018
卷: 32, 期: 4 语种: 英语
英文关键词: Argo
; atmospheric convection
; deep water
; disequilibrium
; dissolved oxygen
; gas exchange
; parameterization
; prediction
; saturation
; thermohaline structure
; winter
; Atlantic Ocean
; Labrador Sea
学科: Argo
; convection
; deep water formation
; Labrador Sea
; oxygen saturation
中文摘要: Deep water formation supplies oxygen-rich water to the deep sea, spreading throughout the ocean by means of the global thermohaline circulation. Models suggest that dissolved gases in newly formed deep water do not come to equilibrium with the atmosphere. However, direct measurements during wintertime convection are scarce, and the controls over the extent of these disequilibria are poorly quantified. Here we show that, when convection reached deeper than 800 m, oxygen in the Labrador Sea was consistently undersaturated at −6.1% to −7.6% at the end of convection. Deeper convection resulted in greater undersaturation, while convection ending later in the year resulted in values closer to equilibrium, from which we produce a predictive relationship. We use dissolved oxygen data from six profiling Argo floats in the Labrador Sea between 2003 and 2016, allowing direct observations of wintertime convection. Three of the six optode oxygen sensors displayed substantial average in situ drift of −3.03 μmol O2 kg−1 yr−1 (−0.94% O2 yr−1), which we corrected to stable deepwater oxygen values from repeat ship surveys. Observations of low oxygen intrusions during restratification and a simple mixing calculation demonstrate that lateral processes act to lower the oxygen inventory of the central Labrador Sea. This suggests that the Labrador Sea is a net sink for atmospheric oxygen, but uncertainties in parameterizing gas exchange limit our ability to quantify the net uptake. Our results constrain the oxygen concentration of newly formed Labrador Sea Water and allow more precise estimates of oxygen utilization and nutrient regeneration in this water mass. ©2018. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160238
Appears in Collections: 气候变化与战略
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作者单位: School of Earth and Ocean Sciences, University of Victoria, Victoria, BC, Canada; Maurice-Lamontagne Institute, Fisheries and Oceans Canada, Mont-Joli, QC, Canada; Bedford Institute of Oceanography, Fisheries and Oceans Canada, Dartmouth, NS, Canada; Ifremer, Laboratoire d'Océanographie Physique et Spatiale, Plouzané, France
Recommended Citation:
Wolf M.K.,Hamme R.C.,Gilbert D.,et al. Oxygen Saturation Surrounding Deep Water Formation Events in the Labrador Sea From Argo-O2 Data[J]. Global Biogeochemical Cycles,2018-01-01,32(4)