The Thermohaline Modes of the Global Ocean
The Thermohaline Modes of the Global Ocean
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DOI：
10.1175/jpo-d-19-0120.1
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发表时间：
2019-09
影响因子：
3.5
通讯作者：
Etienne Pauthenet;F. Roquet;G. Madec;J. Sallée;D. Nerini
中科院分区：
文献类型：
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作者：
Etienne Pauthenet;F. Roquet;G. Madec;J. Sallée;D. Nerini
使用多元函数主成分分析 (FPCA)，将海洋的前 2000 米温盐结构统计分解为垂直温盐模式。该方法应用于每月等密度和混合层海洋气候学（MIMOC）。前三种模式占联合温度和盐度 (T-S) 方差的 92%，这产生了令人惊讶的良好降维效果。第一个模态（方差为 69%）与温跃层深度相关并描绘了副热带环流。第二种模态（18%）主要由盐度驱动，主要表现出北太平洋和大西洋盆地与南大洋绕极地咸水深水区之间的不对称性。第三种模式（5%）识别低盐度和高盐度的中间水域，与上层海洋的淡水输入共同变化。前三种模态定义的空间中海洋的表示提供了全球温盐结构的简单可视化，该结构引人注目地强调了南大洋在将水团连接和分配到其他盆地方面的作用。垂直温盐模式为模型和观测数据比较提供了方便的框架。这是通过将重复的太平洋剖面 P16 与来自实时地转海洋学阵列 (ARGO) 全球剖面浮标阵列的剖面投影到气候学 MIMOC 定义的模式上来说明的。这些温盐模式具有水团识别和热量和盐含量稳健分析的潜力。
The first 2000 m of the global thermohaline structure of the ocean are statistically decomposed into vertical thermohaline modes, using a multivariate functional principal component analysis (FPCA). This method is applied on the Monthly Isopycnal and Mixed-Layer Ocean Climatology (MIMOC). The first three modes account for 92% of the joint temperature and salinity (T–S) variance, which yields a surprisingly good reduction of dimensionality. The first mode (69% of the variance) is related to the thermocline depth and delineates the subtropical gyres. The second mode (18%) is mostly driven by salinity and mainly displays the asymmetry between the North Pacific and Atlantic basins and the salty circumpolar deep waters in the Southern Ocean. The third mode (5%) identifies the low- and high-salinity intermediate waters, covarying with the freshwater inputs of the upper ocean. The representation of the ocean in the space defined by the first three modes offers a simple visualization of the global thermohaline structure that strikingly emphasizes the role of the Southern Ocean in linking and distributing water masses to the other basins. The vertical thermohaline modes offer a convenient framework for model and observation data comparison. This is illustrated by projecting the repeated Pacific section P16 together with profiles from the Array for Real-Time Geostrophic Oceanography (ARGO) global array of profiling floats on the modes defined with the climatology MIMOC. These thermohaline modes have a potential for water mass identification and robust analysis of heat and salt content.