气候变化领域集成服务门户(CCPortal): Variability of Dissolved Oxygen in the Bottom Layer of the Southern Senegalese Shelf

CCPortal

DOI	10.1029/2020JC016854
	Variability of Dissolved Oxygen in the Bottom Layer of the Southern Senegalese Shelf
	Tall A.W.; Machu E.; Echevin V.; Capet X.; Pietri A.; Corréa K.; Sall S.M.; Lazar A.
发表日期	2021
ISSN	21699275
卷号	126 期号:5
英文摘要	The observation station “Melax” was deployed in 2015 on the wide and shallow south Senegalese shelf to study the ocean dynamics, air-sea interactions, and dissolved oxygen (DO) cycle. Data from February 2015 to August 2016 were used to study the main physical processes affecting the variability of DO in the bottom layer (∼30 m depth) on time scales ranging from tidal to seasonal. Between November and May, wind-driven upwelling provides phytoplankton enrichment of the surface layers and brings cold, salty, and depleted DO on the shelf. Water properties at Melax vary depending on the source waters located at the shelf edge. The DO concentration changes between the shelf edge and Melax are broadly consistent with the inferred respiration rates estimated in previous studies. In contrast, the monsoon season (July–October) is characterized by weak westerly winds and northward currents. Bottom waters are warmer, fresher, and more oxygenated. The slower circulation in this period allows a stronger decoupling between the water properties of the waters observed at Melax and those of the source waters. Stratification strengthening near the bottom layer inhibits vertical mixing and induces strong high-frequency variability in properties caused by internal tide-generated waves. Intense upwelling events can deepen the mixed layer and intermittently transform the bottom layer waters (locally or remotely). Relaxation events associated with current reversals significantly modify their properties. Coastal trapped waves constitute a distant forcing that can act year-round, impacting both shelf waters and source regions. © 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/186335
作者单位	Laboratoire de Physique de l'Atmosphère et de l'Océan Siméon Fongang, Université Cheikh Anta DIOP de Dakar, Ecole Supérieure Polytechnique, Dakar, Senegal; Université de Bretagne Occidentale, CNRS, IRD, Ifremer, Laboratoire d'Océanographie Physique et Spatiale (LOPS), IUEM, Brest, France; LOCEAN-IPSL, IRD/CNRS/Sorbonne Université (UPMC)/MNHN, UMR 7159, Paris, France; Instituto del Mar del Peru (IMARPE), Esquina General Gamarra y Valle, Callao, Peru
推荐引用方式 GB/T 7714	Tall A.W.,Machu E.,Echevin V.,et al. Variability of Dissolved Oxygen in the Bottom Layer of the Southern Senegalese Shelf[J],2021,126(5).
APA	Tall A.W..,Machu E..,Echevin V..,Capet X..,Pietri A..,...&Lazar A..(2021).Variability of Dissolved Oxygen in the Bottom Layer of the Southern Senegalese Shelf.Journal of Geophysical Research: Oceans,126(5).
MLA	Tall A.W.,et al."Variability of Dissolved Oxygen in the Bottom Layer of the Southern Senegalese Shelf".Journal of Geophysical Research: Oceans 126.5(2021).