Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1002/2017GL074169 |
How important are diapycnal mixing and geothermal heating for the deep circulation of the Western Mediterranean? | |
Ferron, B.1; Aubertot, P. Bouruet2; Cuypers, Y.2; Schroeder, K.3; Borghini, M.4 | |
2017-08-16 | |
发表期刊 | GEOPHYSICAL RESEARCH LETTERS |
ISSN | 0094-8276 |
EISSN | 1944-8007 |
出版年 | 2017 |
卷号 | 44期号:15 |
文章类型 | Article |
语种 | 英语 |
国家 | France; Italy |
英文摘要 | The dissipation rate of turbulent kinetic energy epsilon and the associated diapycnal turbulent mixing is inferred from a set of microstructure observations collected over several cruises from year 2012 to 2014. The geographical distribution of epsilon highlights several regions of enhanced levels of turbulence ranging from 10(-9) to 10(-6) W kg(-1): the Sicily Channel, the Corsica Channel, and the Ligurian Sea. Elsewhere, epsilon was small, often below 10(-10) W kg(-1). Below 1300 m, geothermal heating provides three-fold more buoyancy than small-scale turbulence. Geothermal heating and turbulent diffusion provide enough buoyancy to balance 15% to 50% of a mean yearly deep water formation rate of 0.9 to 0.3 sverdrup (10(6) m(3)/s), respectively. The remaining part has to eventually overflow through the Strait of Gibraltar. Plain Language Summary During the winter season in the western Mediterranean, an invisible river transports dense waters formed at the surface by cold winds down to the ocean bottom at a rate sixfold larger than the Amazon River discharge. This winter flow increases the volume of dense waters present at depth. However, two mechanisms supply buoyancy and erode the volume of dense waters. One is heat coming from the seafloor and is called geothermal heating. The other is heat coming from the surface and is powered by natural fluid turbulence, in the same way as producing turbulence with a teaspoon mixes milk and tea vertically. Here we use historical data of geothermal heating and observations collected in 2012-2014 that measure for the first time the intensity of the oceanic turbulence to diagnose whether the winter volume increase of dense water at depth can be balanced by heat coming from the surface and the seafloor. Observations suggest that geothermal heating is threefold more efficient than oceanic turbulence in bringing heat to the dense waters at depth. But the addition of heat by both oceanic turbulence and geothermal heating is not strong enough to erode the import of winter dense water at depth. |
领域 | 气候变化 |
收录类别 | SCI-E |
WOS记录号 | WOS:000408379000033 |
WOS关键词 | WATER FORMATION ; SEA ; OCEAN ; VARIABILITY ; CONVECTION ; DEPTH ; PARAMETERIZATION ; MICROSTRUCTURE ; DISSIPATION ; TURBULENCE |
WOS类目 | Geosciences, Multidisciplinary |
WOS研究方向 | Geology |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/28217 |
专题 | 气候变化 |
作者单位 | 1.Univ Brest, CNRS, IFREMER, IRD,Lab Oceanog Phys & Spatiale,IUEM, Brest, France; 2.Univ Paris 06, Sorbonne Univ, LOCEAN, IPSL,UPMC,CNRS,IRD,MNHN, Paris, France; 3.CNR ISMAR Arsenale, Venice, Italy; 4.CNR ISMAR, Sede Di La Spezia, Pozzuolo Di Ler, Italy |
推荐引用方式 GB/T 7714 | Ferron, B.,Aubertot, P. Bouruet,Cuypers, Y.,et al. How important are diapycnal mixing and geothermal heating for the deep circulation of the Western Mediterranean?[J]. GEOPHYSICAL RESEARCH LETTERS,2017,44(15). |
APA | Ferron, B.,Aubertot, P. Bouruet,Cuypers, Y.,Schroeder, K.,&Borghini, M..(2017).How important are diapycnal mixing and geothermal heating for the deep circulation of the Western Mediterranean?.GEOPHYSICAL RESEARCH LETTERS,44(15). |
MLA | Ferron, B.,et al."How important are diapycnal mixing and geothermal heating for the deep circulation of the Western Mediterranean?".GEOPHYSICAL RESEARCH LETTERS 44.15(2017). |
条目包含的文件 | 条目无相关文件。 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论