Moored Turbulence Measurements using Pulse-Coherent Doppler Sonar
Moored Turbulence Measurements using Pulse-Coherent Doppler Sonar
复制标题
使用脉冲相干多普勒声纳进行系泊湍流测量
DOI：
10.1175/jtech-d-21-0005.1
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发表时间：
2021
影响因子：
2.2
通讯作者：
Le Bel, Deborah
中科院分区：
文献类型：
--
作者：
Zippel, Seth F.;Farrar, J. Thomas;Zappa, Christopher J.;Miller, Una;Laurent, Louis St.;Ijichi, Takashi;Weller, Robert A.;McRaven, Leah;Nylund, Sven;Le Bel, Deborah
上层海洋湍流是热量、动量和气体通过海气界面交换的核心，因此在天气和气候中起着重要作用。目前对上层海洋混合缺乏了解，常常导致模式错误地表示混合层深度和海面温度。在一定程度上，由于测量固定系泊处的湍流很困难，进展受到限制。固定系泊处可以同时测量长时间的海面通量和上层海洋分层。在这里，我们介绍了一种直接波数法测量湍流动能（TKE）耗散ratesϵfrom使用脉冲相干ADCPs长寿命系泊。我们讨论了adcp的最佳规划，用于系泊的强大机械设计，以最大化数据返回，以及数据处理技术，包括相位模糊解包裹，频谱分析和仪器响应校正。该方法被用于盐度过程上层海洋区域研究（SPURS），以收集两年的数据集。我们发现系泊导出的TKE耗散率与安装在滑翔机上的微观结构剪切探头在其两个独立的2周任务期间对O(10−8)≤λ≤O(10−5)m2s−3的估算值相比更理想。两个平台湍流估计的不一致时期与垂直温度分布的差异相吻合，这可能表明屏障层可以在1-10公里的水平尺度上实质性地调节上层海洋湍流。我们还发现，在12.5 m和7 m两个不同系泊处的耗散估计与夜间强对流期间的表面浮力通量一致，与经典边界层理论一致。
Upper-ocean turbulence is central to the exchanges of heat, momentum, and gases across the air–sea interface and therefore plays a large role in weather and climate. Current understanding of upper-ocean mixing is lacking, often leading models to misrepresent mixed layer depths and sea surface temperature. In part, progress has been limited by the difficulty of measuring turbulence from fixed moorings that can simultaneously measure surface fluxes and upper-ocean stratification over long time periods. Here we introduce a direct wavenumber method for measuring turbulent kinetic energy (TKE) dissipation ratesϵfrom long-enduring moorings using pulse-coherent ADCPs. We discuss optimal programming of the ADCPs, a robust mechanical design for use on a mooring to maximize data return, and data processing techniques including phase-ambiguity unwrapping, spectral analysis, and a correction for instrument response. The method was used in the Salinity Processes Upper-Ocean Regional Study (SPURS) to collect two year-long datasets. We find that the mooring-derived TKE dissipation rates compare favorably to estimates made nearby from a microstructure shear probe mounted to a glider during its two separate 2-week missions forO(10−8) ≤ϵ≤O(10−5) m2s−3. Periods of disagreement between turbulence estimates from the two platforms coincide with differences in vertical temperature profiles, which may indicate that barrier layers can substantially modulate upper-ocean turbulence over horizontal scales of 1–10 km. We also find that dissipation estimates from two different moorings at 12.5 and at 7 m are in agreement with the surface buoyancy flux during periods of strong nighttime convection, consistent with classic boundary layer theory.
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影响因子：
2.2
作者：
Yanwei Zhang;J. Moum
通讯作者：
Yanwei Zhang;J. Moum
影响因子：
--
作者：
A. Bogdanoff
通讯作者：
A. Bogdanoff
使用自主 Nortek 声学多普勒电流剖面仪观察精细海洋速度结构。
影响因子：
2.2
作者：
A. Shcherbina;E. D’Asaro;S. Nylund
通讯作者：
S. Nylund
单波束脉冲间相干多普勒轮廓仪的性能
影响因子：
4.1
作者：
L. Zedel;A. Hay;R. Cabrera;A. Lohrmann
通讯作者：
A. Lohrmann
影响因子：
5.2
作者：
G. Sutherland;G. Reverdin;L. Marié;B. Ward
通讯作者：
G. Sutherland;G. Reverdin;L. Marié;B. Ward