Significant salinity increase in subsurface waters of the South China Sea during 2016–2017

The South China Sea(SCS) is the largest semi-enclosed marginal sea in the North Pacific. Salinity changes in the SCS play an important role in regional and global ocean circulation and the hydrological cycle. However, there are few studies on salinity changes over the SCS due to lack of high-quality and long-term observations. In the past decade, the deployment of floats from the Argo program in the SCS and their accumulated temperature and salinity profiles have made it possible for us to examine salinity changes over the entire basin. In this study,salinity changes were investigated with Argo and underwater glider temperature and salinity observations and gridded temperature–salinity objective analyses(UK Met Office Hadley Centre EN4.2.1 objective analysis and China Argo Real-time Data Center BOA_Argo). The results indicated that the subsurface water in the entire SCS became significantly saltier during 2016–2017. The most significant salinity increase was found during 2016 in the northeastern SCS. The subsurface water in the northeastern SCS exhibited a salinity maximum above 35, which was recorded by three Argo floats during 2015–2016. Such high salinity water was rarely observed and reported prior to the Argo era. Average salinity of 2016–2017 along the 25.5σ_θ–23.5σ_θ isopycnal surfaces in the whole SCS is 0.014-0.130 higher than the climatology. Increases in subsurface salinity started from the northeastern SCS and extended southwestward gradually. Moreover, the subsurface salinity changes, especially in the northern SCS,exhibited a semiannual lead behind the subsurface Luzon Strait transport. Further analysis indicated that the predominance of advection, driven by subsurface Luzon Strait transport, led to salinification along the western boundary of the SCS. In other parts of the SCS, negative wind stress curl trends tended to preserve the high salinity characteristics of the subsurface water.     

The upper ocean response to tropical cyclones in the northwestern Pacific analyzed with Argo data

A large number of autonomous profiling floats deployed in global oceans have provided abundant temperature and salinity profiles of the upper ocean. Many floats occasionally profile observations during the passage of tropical cyclones. These in-situ observations are valuable and useful in studying the ocean’s response to tropical cyclones, which are rarely observed due to harsh weather conditions. In this paper, the upper ocean response to the tropical cyclones in the northwestern Pacific during 2000–2005 is analyzed and discussed based on the data from Argo profiling floats. Results suggest that the passage of tropical cyclones caused the deepening of mixed layer depth (MLD), cooling of mixed layer temperature (MLT), and freshening of mixed layer salinity (MLS). The change in MLT is negatively correlated to wind speed. The cooling of the MLT extended for 50–150 km on the right side of the cyclone track. The change of MLS is almost symmetrical in distribution on both sides of the track, and the change of MLD is negatively correlated to pre-cyclone initial MLD.     

利用Argo资料研究2001-2004年期间西北太平洋海洋上层对热带气旋的响应

利用Argo剖面浮标观测资料,对2001-2004年11月期间西北太平洋热带气旋经过后海洋上层的响应作了分析研究.结果显示,热带气旋经过后,55.6%的观测剖面其混合层深度会加深,范围在0-60m,并且在气旋过后5d内更为明显;由于混合加剧,大约有77.8%的观测剖面其混合层温度会下降,最多达5℃;61.1%的混合层盐度会下降,平均降盐约0.12;表层流速增大的占54%,平均增大30cm·s,表层流速的变化与风速的大小呈正相关,相关系数仅为0.06;混合层内温度变化与热带气旋风速呈负相关,相关系数为-0.15;混合层温度下降有明显的右偏现象,在气旋路径右侧50-150km处,温度下降尤为明显,而混合层盐度在气旋路径两侧的变化基本呈对称状分布;混合层深度在气旋路径右侧加深更为明显,在右侧100 150km范围内达到最大;混合层深度的变化与气旋经过前混合层的初始深度呈明显的负相关,相关系数达-0.42.     

智慧海洋国际共享应用平台发展趋势及其对策建议

当前,我国正在全面开展智慧海洋建设,各种新研发观测平台不断涌现,但是围绕智慧海洋的信息化建设仍显落后,在数据管理、质量控制方法和系统开发等方面与发达国家仍存在较大差距。文章通过分析国内外海洋共享应用平台的发展趋势及其特点,从数据管理方法、质量控制和系统设计开发等多个方面找出差距所在。研究表明,与国外相比,国内存在共享平台业务化运行不多的问题,为实现数据的规范化,并给出尽快制定针对不同观测平台数据管理规范、加强数据质量控制方法研究、加强具备专业知识的系统设计人才培养等建议。     

AUTOSAL8400B型实验室盐度计及其应用

AUTOSAL 84 0 0 B型实验室盐度计是一种高精度的测量海水电导率 (换算盐度 )的仪器 ,其测量精度可达到± 0 .0 0 2 psu,被广泛应用于海洋环境测量以及现场和实验室仪器定标等领域。它的高精度测量特性在深海大洋中显得尤其重要。本文将详细介绍该盐度计的性能 ,以及操作步骤和使用技巧等 ,以便充分展示和发挥该盐度计的作用     

全球Argo实时海洋观测网全面建成

文中较详尽地介绍了全球Argo实时海洋观测网建设现状,以及Argo资料在相关领域应用研究中所取得的成果,揭示了Argo资料广阔的应用研究前景。但要实现国际Argo计划的最终目标,尚需各参与国不遗余力。