The South Pacific Subtropical Mode Water in the Tasman Sea

From the synopical CTD sections in the WOCE PR11 repeated cruises, the South Pacific Subtropical Mode Water (SPSTMW) has been identified in the region of the Tasman Front Extension (TFE) around 29?S to the east of Australia. In the depth range of 150-250 m, the SPSTMW appears as a thermostad with vertical temperature gradient lower than 1.6℃(100 m)-1 and a tem- perature range of 16.5-19.5℃ and as a pycnostad with PV lower than 2×10-10 m-1 s-1 and a potential density range of 25.4-26.0 kg m-3. Like the subtropical mode waters in the North Atlantic and North Pacific, the formation of the SPSTMW is associated with the convective mixing during the austral wintertime as manifested from the time series of the Argo floats. And cold water entrains into the mixed layer with the deepening mixed layer from September to the middle of October. During the wintertime formation process, mesoscale eddies prevailing in the TFE region play an important role in the SPSTMW formation, and have a great effect on the SPSTMW distribution in the next year. The deeper (shallower) mixed layer in wintertime, consistent with the depressed (uplifted) permanent thermocline, is formed by the anticyclonic (cyclonic) eddies, and the substantial mode water thicker than 50 m is mainly found in the region of the anticyclonic eddies where the permanent thermocline is deeper than 450 m.     

水面无线自组网装备研发与水动力学监测应用研究

应用窄带物联网技术,研发了一种能够快速构建半径100 km的水面无线网络,并通过投放大量抛弃式带北斗定位的微型浮标,动态采集水动力学数据.该技术能够解决采用传统海洋水动力学监测利用锚泊式大型浮标,固定在一个位置上采集数据的方法成本高、数据精细化程度不够的问题.由大量的海洋试验和研究证明,该方法在泥沙沉积、漂浮垃圾追踪、...     

A nested pre-operational model for the Egyptian shelf zone: Model configuration and validation/calibration

We explored the variability of the Egyptian shelf zone circulation connected to atmospheric forcing by means of a numerical simulation of the general circulation. A high resolution model grid was used at 1/60° horizontal resolution and 25 sigma layers. The simulation was carried out using the most recent version of the Princeton Ocean Model (POM). The initialised model was run the whole year of 2006 using the analysis forcing data for the same year obtained from ECMWF and MFS (Mediterranean Forecasting System, Pinardi et al., 2003). The model skills were evaluated by means of the root mean square error (RMSE) and correlations. The Egyptian Shelf Model (EGYSHM) simulation suggests the presence of an Egyptian Shelf Slope Current (ESSC), which is flowing eastward at different depths in the domain. We found that the maximum velocity of the ESSC [0.25 m/s] is located near the continental slope during the summer time, while in winter the velocity of ESSC is weaker [0.12 m/s] in the same location. The ESSC appears to be directly affected by Mersa-Matruh gyre system. EGYSHM reproduced the main region circulation patterns, especially after adding the Nile River outflow. We found that wind stress is crucial to force the circulation of the Egyptian shelf zone. EGYSHM SST was significantly correlated to satellite SST in all months at a 95% confidence limit, with a maximum of 0.9743 which was obtained in May 2006. The RMSE between EGYSHM and Argo floats salinity data was about 0.09. We compared our results with satellite altimetry to verify the positions and shapes of mesoscale features.     

TOPEX/Poseidon and Jason-1: Absolute Calibration in Bass Strait, Australia

Updated absolute calibration results from Bass Strait, Australia, are presented for the TOPEX/Poseidon (T/P) and Jason-1 altimeter missions. Data from an oceanographic mooring array and coastal tide gauge have been used in addition to the previously described episodic GPS buoy deployments. The results represent a significant improvement in absolute bias estimates for the Bass Strait site. The extended methodology has allowed comparison between the altimeter and in situ data on a cycle-by-cycle basis over the duration of the dedicated calibration phase (formation flight period) of the Jason-1 mission. In addition, it has allowed absolute bias results to be extended to include all cycles since the T/P launch, and all Jason-1 data up to cycle 60. Updated estimates and formal 1-sigma uncertainties of the absolute bias computed throughout the formation flight period are 0 ± 14 mm for T/P and +152 + 13 mm for Jason-1 (for the GDR POE orbits). When JPL GPS orbits are used for cycles 1 to 60, the Jason-1 bias estimate is 131 mm, virtually identical to the NASA estimate from the Harvest Platform off California calculated with the GPS orbits and not significantly different to the CNES estimate from Corsica. The inference of geographically correlated errors in the GDR POE orbits (estimated to be approximately 17 mm at Bass Strait) highlights the importance of maintaining globally distributed verification sites and makes it clear that further work is required to improve our understanding of the Jason-1 instrument and algorithm behavior.     

OSB-1型近海测波浮标网岸站数据处理系统

本文报道OSB-1型近海测波浮标网岸站数据处理系统。介绍了将APPLEⅠPlUS微机用于该系统的设计思想和实现方法。同时还给出系统框图、各功能模块逻辑流程图以及波谱分析程序框图。对该系统的使用情况也作了简要的叙述。笔者以汇编语言为基础,采用模块化技术编制的应用软件包,使该微机数据处理的速度得到提高并减少了所需要的内存容量,满足了浮标网对岸站数据处理系统的有关要求,得到较好的应用。     

棉兰老岛以东反气旋涡的Argo观测研究

报道了2003年1月至10月期间,由布放于西北太平洋中的Argo剖面浮标捕获的位于棉兰老岛以东海域的反气旋涡。该涡中心位于8.7°N、127.6°E附近,距大陆坡不远,沿等深线走向呈椭圆形分布。其长轴(NW-SE)约200km,短轴(NE-SW)长约120km。Argo浮标的漂移轨迹及其在表层及1 500db层的漂移速度场表明,该反气旋涡位于温跃层以下,中层海洋特征。在1 500db层上,涡的外围平均切向速度为11.9—14.0cm.s-1,旋转周期约为40d。温、盐度断面分布表明,该反气旋涡内的温盐结构非常复杂,可能与源自南、北半球的中层水团在涡旋内交汇并发生变性有关。     

JBY1-1型波浪浮标检定装置

在国家海洋局支持下，国家海洋标准计量中心成功研制了JBY1-1型波浪浮标检定装置。该装置填补了我国波浪浮标检定领域的空白，在波高、波周期等主要技术性能上优于欧美发达国家同类设备。本文详细介绍了该装置的结构、组成、主要技术指标，关键技术及实际应用情况等。     

定位浮标在波浪中的动态响应

定位浮标是为满足水下蛙人部队定位要求而设计的。定位浮标的升沉和横摇运动对海水中换能器阵的水声定位精度影响较大，而使定位浮标产生这两种振荡的主要激励源是波浪。在不考虑流和风对浮标作用的前提下，以规则波作为激励源，研究了定位浮标在波浪激励下的两种运动模型，然后用计算机对横摇和升沉运动模型进行了仿真，最后从运动模型出发提出了减少浮标振幅的有效办法，这对定位浮标结构设计有重要意义。     

Numerical study on the reverse drift force of floating BBDB wave energy absorbers

The motions and time-mean horizontal drift forces of floating backward-bent duct buoy wave energy absorbers in regular waves are calculated taking account of the oscillating surface-pressure due to the pressure drop in the air chamber above the oscillating water column within the scope of the linear wave theory. The present numerical results show that the time-mean drift forces of backward-bent duct buoys are in the reverse direction of propagation of the incident waves over specific frequency ranges as found by McCormick through his experimental work. The drift force has been calculated by the near-field method. A brief discussion on Maruo’s formula which shows that the time-mean drift force must be in the direction of propagation of the incident waves, has also been presented.     

一种增设于Waverider测波仪的数据自记系统

本文介绍一种用MCS-51单片微机作为控制器,用大容量静态RAM作为存储器,以纯电子线路组成硬件线路,配合相应的控制软件,联合构成稳定可靠、低功耗的自记式波浪数据采集系统。该系统增设在Waverider浮标(67780系列)中,使之成为自记与遥测并存的双制式测波浮标,海上实地投放使用已获得成功.