Tidal-induced mixing and diapycnal nutrient fluxes in the Mauritanian upwelling region
Tidal-induced mixing and diapycnal nutrient fluxes in the Mauritanian upwelling region
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毛里塔尼亚上升流区域潮汐引起的混合和二重营养物通量
DOI：
10.1029/2009jc005940
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发表时间：
2010
影响因子：
--
通讯作者：
H. Bange
中科院分区：
文献类型：
--
作者：
Schafstall;M. Dengler;P. Brandt;H. Bange
毛里塔尼亚沿海地区是世界海洋中生物产量最高的上升流地区之一。在最大上升流季节进行的船上观测和短期系泊观测用于研究底浪混合过程并量化营养物质的底浪通量。观测结果表明，在大陆斜坡的大部分地区发生的近临界角有利于强烈的潮汐-地形相互作用。系泊速度观测表明存在高度非线性的内波和孔，在浮力频率附近内波谱水平明显升高。斜坡和陆架处的湍流动能耗散率由上层200米的微观结构测量确定，平均为[= 5 × 10−8W kg−1]。在靠近陆架断裂的大陆斜坡处，发现耗散率特别高，与离岸较远的耗散率相比，耗散率提高了100到1000倍。每单位体积的垂直积分耗散率在大陆坡上部最强，可达30 mW m−2。大陆架区域和公海湍流耗散率的细尺度参数化与实测耗散率的比较表明，在再现观测结果方面存在不足。混合层底部大陆坡上方的沉坡硝酸盐通量平均值为12 × 10−2μmol m−2s−1，是迄今公布的最大通量之一。然而，它们似乎只占上升流地区净群落产量的一小部分（10%至25%）。
The Mauritanian coastal area is one of the most biologically productive upwelling regions in the world ocean. Shipboard observations carried out during maximum upwelling season and short‐term moored observations are used to investigate diapycnal mixing processes and to quantify diapycnal fluxes of nutrients. The observations indicate strong tide‐topography interactions that are favored by near‐critical angles occurring on large parts of the continental slope. Moored velocity observations reveal the existence of highly nonlinear internal waves and bores and levels of internal wave spectra are strongly elevated near the buoyancy frequency. Dissipation rates of turbulent kinetic energy at the slope and shelf determined from microstructure measurements in the upper 200 m averages to ɛ = 5 × 10−8W kg−1. Particularly elevated dissipation rates were found at the continental slope close to the shelf break, being enhanced by a factor of 100 to 1000 compared to dissipation rates farther offshore. Vertically integrated dissipation rates per unit volume are strongest at the upper continental slope reaching values of up to 30 mW m−2. A comparison of fine‐scale parameterizations of turbulent dissipation rates for shelf regions and the open ocean to the measured dissipation rates indicates deficiencies in reproducing the observations. Diapycnal nitrate fluxes above the continental slope at the base of the mixed layer yielding a mean value of 12 × 10−2μmol m−2s−1are amongst the largest published to date. However, they seem to only represent a minor contribution (10% to 25%) to the net community production in the upwelling region.
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影响因子：
64.8
作者：
PINGREE, RD;MARDELL, GT;NEW, AL
通讯作者：
NEW, AL
从水文和化学领域推断出上升流区域的生产力1
DOI：
--
发表时间：
1986
期刊：
影响因子：
--
作者：
H. Minas;M. Minas;T. Packard
通讯作者：
T. Packard
影响因子：
2.3
作者：
T. Rippeth;P. Wiles;M. Palmer;J. Sharples;J. F. Tweddle
通讯作者：
T. Rippeth;P. Wiles;M. Palmer;J. Sharples;J. F. Tweddle
影响因子：
3.6
作者：
GARGETT, AE
通讯作者：
GARGETT, AE
DOI：
--
发表时间：
1985
期刊：
影响因子：
--
作者：
C. Eriksen
通讯作者：
C. Eriksen