处理走航式海洋多参数剖面测量系统(MVP)温度和电导率滞后效应的方法

走航式海洋多参数剖面测量系统(moving vessel profiler,MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配,MVP下放速度过快(峰值速度4 m/s)而造成非常明显的盐度尖峰现象。本研究结合Fofonoff(F)法、时间常数指数递归数字滤波(Giles and McDougall,GM)法和Grose提出的盐度尖峰订正方案,提出了一种新的方法,即MCT(match conductivity and temperature response time)法,通过对压力、温度和电导率传感器进行响应时间的匹配来减弱盐度尖峰。将SBE-9型CTD资料作为标准,发现订正后的资料与CTD盐度曲线的互相关系数为0.917,误差比订正前减小80%。对比35°N断面修正前后的盐度资料,订正后温盐跃层处出现的低盐区域消失。MVP的应用比常规海洋调查仪器CTD对于海洋现象的观测更有优势。     

多源温盐资料排重处理的一种方法

多源温盐资料存在大量重复现象,大大影响了这些资料的融合应用价值。本文根据多源温盐资料的重复现象,结合实际业务工作经验,提出了重复条件组合排重法这一模型(缩写RRM-CRC),并介绍了温盐资料排重业务化流程。利用该模型和业务流程,可以有效提高温盐资料的排重效率,在其他资料的排重处理中也有重要的借鉴意义。     

浅水多波束测深资料处理关键技术探讨

为提高浅水多波束测深资料处理成果质量,基于澳门海域浅水多波束测深资料,提出应用POS/MV大地高数据计算实时潮汐数据,探讨了浅水多波束测深资料声速校正方法.结果 表明,经过潮汐改正和声速改正后资料处理成果质量明显提高,解决了浅水多波束测深资料处理中的难题,本方法可为浅水多波束测深资料处理提供重要指导.     

A method of simultaneous analysis of wind and temperature profile data over the water surface by use of the method of least squares

Priestley’s 1959 discussion concerning the estimations of momentum flux and of heat flux from profile observations of wind and temperature, stating that the closeness of the curve fitting is deceptive, is first critically re-examined. Then a method is proposed to estimate vertical flux of momentum and heat over the water surface, from the combined data of of wind speed and temperature are assumed to have similar log-linear profiles, and the most probable profiles are determined by applying the method of least squares simultaneously to wind and temperature data. Consequently, the most probable values of vertical flux of momentum and heat may be estimated to satisfy as much as possible observed data of both wind and temperature simultaneously. The coefficient of the linear term of the log-linear profile, which is treated as an indeterminate coefficient in this method, may be determined from each observed data as a function of stability length. By tentatively applying the method to Rider’s 1954 data it is found that the coefficient shows a characteristic behavior with the stability length.     

A data processing method for MAPR hydrothermal plume turbidity data and its application in the Precious Stone Mountain hydrothermal field

Hydrothermal plume is an important constituent of seabed hydrothermal circulation and is also one of the characteristics of active hydrothermal vents. Portable Miniature Autonomous Plume Recorders （MAPR） attached to a towed deep-sea instrument was used to search for hydrothermal plumes and hydrothermal vents. We introduced the basic principle of MAPR based on deep towing technology to detect plumes, then analyzed the factors affecting the quality of the MAPR data and presented a data correction method for MAPR, including instrument location correction, noise reduction processing, system error elimination and seawater background reduction. Finally we applied the method to analyze MAPR data obtained during the Chinese DY115-21 cruise on R/VDayang Iin the “Precious Stone Mountain” hydrothermal field on the Gala-pagos Microplate. The results provided a better understanding of the distribution of the hydrothermal activ-ity in this field, indicating the presence of a new hydrothermal vent.     

A shipborne wave-recording system with digital data processing

A shipborne wave-recording system which consists of a sonic wave gauge, accelerometers, gyroscopes and a computer system is described. Signals from the measuring apparatus are fed directly into a shipborne digital computer system at a prescribed sampling rate. The time series of wave heights and the acceleration are transformed into Fourier series using an algorithm of Fast Fourier Transform. Errors contained in the observed wave heights due to ship motion are corrected in the Fourier series by using the Fourier coefficients for the vertical acceleration. Power spectra and waveforms can also be calculated in a short time with this system from Fourier coefficients. Examples of the observational results obtained in the central part of the East China Sea in 1969 are presented.     

A deep sea temperature and pressure sensor for tidal measurement

With ever increasing information being collected by the offshore continental shelf tide gauges, it became inevitable that researches into ocean tides would require instrumentation to collect tidal data in the deep oceans.This paper briefly describes the temperature and pressure sensors developed, and used by the Institute of Oceanographic Sciences (Wormley), in response to this requirement. Also described are the techniques and equipment used to calibrate these sensors.The deep sea tide gauges, each of which include two pressure and one temperature sensor, have now been operationally deployed on four occasions at pressures up to 300 bars (3000 m) providing well over 100 days of tidal data. In an international exercise to evaluate the performance of existing deep sea pressure sensors, results show that the unit described in this paper compares favourably with the other sensors. For example, the amplitude of the semi-diurnal components were within 1% of the average value, determined by all the sensors. The temperature sensor has an operational range within the limits — 1° and + 40°C and exhibiting a stability of the order 8 milli°C/month.     

A new algorithm for automatic processing of bathymetric data

A sea-floor map can be obtained from sonar data using the supplied sonar system software or one of several public domain or proprietary systems. With any of these solutions, the process of production of a sea-floor map is unnecessarily time consuming in the absence of a systematic and efficient solution to the problem of identification of erroneous data (outliers). We present an algorithm to fit bathymetric data and to automatically deal with outliers. The most important characteristics of the algorithm are: production of a triangulated map in which the local spatial resolution and the local known accuracy are dependent both on the sea-floor topography and the data noise amplitude, automatic identification of outliers, intrinsic modularity of the program suitable for a multiprocessor environment, low computing cost, and minimal operator intervention. The algorithm is described and its parameters are defined on the basis of their effect on the results. The results of the application of the algorithm to synthetic data with and without outliers demonstrate its behavior on a known "sea floor". The results of the algorithm on real data and its performances (in term of speed and fitting error) are also tested.     

基于荧光猝灭溶解氧传感器的校准方法研究

溶解氧是海洋水质监测的常规关键参数,基于荧光猝灭原理研制的溶解氧传感器具有准确度高、稳定性好和可长期在线测量等优点,已经被广泛用于海水溶解氧浓度监测.针对传感器可能发生的数据漂移和显著偏差可能造成的准确度问题,本文设计了一套专门的校准装置和校准方法.通过严格控制校准水体的温度和溶解氧浓度,测量待校准传感器和参比传感器的...     

基于LOG算子的侧扫声呐海底线检测

针对侧扫声呐数据采集的特点,提出了一种基于图像边缘检测技术中LOG算子的海底线检测新方法,用于准确检测海底线从而对侧扫声呐资料进行斜距改正。通过实验数据处理,表明该方法较传统方法具有明显的优势。     

希尔伯特谱白化方法在海洋地震资料高分辨率处理中的应用

针对海洋地震资料高分辨率宽频处理的要求, 也为了克服常规谱白化、反Q滤波等方法无法同时增强时域和频域局部细节的不足, 基于希尔伯特黄变换(HHT)的谱白化方法对海洋地震资料进行高分辨率处理应用研究。对地震记录进行固有模态分解(EMD), 得到不同尺度的IMF分量; 再利用常规谱白化方法对每个分量根据瞬时频率进行合理的振幅均衡; 将均衡后的IMF分量进行反变换重构地震记录, 从而得到高分辨地震数据。通过理论模型和实际地震资料实验, 与常规谱白化方法的对比分析, 表明该方法信号局部时频刻画能力以及相对振幅保真性优于常规方法, 同时表明此方法能够有效增强地震信号时域和频域的分辨率, 使地震剖面更为连续和清晰, 并具有较高的信噪比     

时空混合调制型偏振干涉成像光谱仪数据处理研究

研究了基于Savart偏光镜的偏振干涉成像光谱仪在时空混合调制模式下图像形成、数据分布的特点,论证了视场补偿型偏振干涉成像光谱仪更适用于单色光条件下的时空混合调制工作模式,并提出了时空混合调制模式下数据采集与处理的基本原理及其需要注意的问题与解决方法.最后,应用这种方法对实验获取的干涉图进行了数据处理,并成功复原出了光谱.     

基于遥感数据的三维温度场参数化分析方法研究

为了满足海洋研究以及海洋调查的需求,本文基于Argo剖面和海表面温度数据开发了一个新的拟合三维温度场的算法。选取西北太平洋区域作为验证算法有效的实验海区。该水域的经纬度范围设定为：30°～40°N, 140°～155°E, 水平分辨率为0.25°。深度方向为从海表到2 000 m水深,水域划分为29层。拟合算法首先将Argo温度剖面以5个深度划分为6层,分别为混合层、夹层、温跃层、过渡层、第一深层、第二深层,然后以第一猜想值和线性回归得到的海表面温度作为初始条件重构三维温度场。重构的三维温度场的剖面与原观测剖面的均方根误差较小,相关性较好,表明该算法是合理有效的。     

利用MATLAB实时处理GPS数据

利用MATLAB软件环境,现场接收并实时处理海上地球物理调查过程中的GPS定位数据,剔除原始数据中的跳点,处理定位误差。采用样条拟合对测线进行拟合光滑,绘制各步处理结果的图形,并将处理前后的航向、航速数据及由此计算出的Eotvos改正值绘制成的曲线进行比较,结果表明:由原始数据计算得到的定位误差较大,与实际船体航行的轨迹有一定差距,而用经过MATLAB处理后的数据计算得到的定位误差较小,航向、航速等与船体航行的真实航迹接近,由此计算出的Eotvos改正值的精度也达到了海上重力测量中Eotvos改正的要求,保证了地球物理数据的质量。     

一种多源DEM数据无缝拼接融合方法

针对两个存在重叠区域的多源DEM(digital elevation model)数据,经过坐标转换、高程统一、加密抽稀等初步处理后,在重叠区域内绘制一条多段重叠线并进行等间距节点插值,插值间距与DEM的网格间距一致。然后利用这些节点分别从两个DEM曲面上提取高程值,通过分析同一节点上两个DEM的高程偏差,最后分别对两个DEM重叠线缓冲区内的网格节点进行高程值调整,距离重叠线越近的网格节点,调整幅值越大,反之越小。利用本技术可实现两个DEM在重叠线处实现无缝拼接融合。     

多波束反向散射强度数据处理研究

在探讨多波束测深系统反向散射强度与海底底质类型的关系基础上,研究影响反向散射强度的各种因素,主要分析了海底地形起伏、中央波束区反射信号对反向散射强度的影响,并给出了消除这些影响的方法;将处理后的“纯”反向散射强度数据镶嵌生成海底声像图,为海底底质类型划分以及地貌解译提供了基础数据和辅助判读依据.     

模态试验中传感器优化配置的逐步削减法

讨论了模态实验中传感器的配置问题。以模态置信度MAC矩阵的最大非对角元为目标函数,利用逐步削减法得到传感器的配置,并保留结构振型矩阵的QR分解得到的自由度,提出了传感器配置必须结合优化效果和经济性两方面综合考虑。以一座具有74个可测自由度的海洋平台为算例,采用逐步削减法得到了12个最优传感器位置,并与逐步累积法进行了比较。     

基于最优插值方法的微波-红外辐射计数据融合全球海面温度网格产品

A new 0.1° gridded daily sea surface temperature(SST) data product is presented covering the years 2003–2015. It is created by fusing satellite SST data retrievals from four microwave(Wind Sat, AMSR-E, ASMR2 and HY-2 A RM)and two infrared(MODIS and AVHRR) radiometers(RMs) based on the optimum interpolation(OI) method. The effect of including HY-2 A RM SST data in the fusion product is studied, and the accuracy of the new SST product is determined by various comparisons with moored and drifting buoy measurements. An evaluation using global tropical moored buoy measurements shows that the root mean square error(RMSE) of the new gridded SST product is generally less than 0.5℃. A comparison with US National Data Buoy Center meteorological and oceanographic moored buoy observations shows that the RMSE of the new product is generally less than 0.8℃. A comparison with measurements from drifting buoys shows an RMSE of 0.52–0.69℃. Furthermore, the consistency of the new gridded SST dataset and the Remote Sensing Systems microwave-infrared SST dataset is evaluated, and the result shows that no significant inconsistency exists between these two products.     

Multimegameter-range acoustic data obtained by bottom-mountedhydrophone arrays for measurement of ocean temperature

Acoustic signals transmitted from the ATOC source on Pioneer Seamount off the coast of California have been received at various sites around the Pacific Basin since January 1996. We describe data obtained using bottom-mounted receivers, including US Navy Sound Surveillance System arrays, at ranges up to 5 Mm from the Pioneer Seamount source. Stable identifiable ray arrivals are observed in several cases, but some receiving arrays are not well suited to detecting the direct ray arrivals. At 5-Mm range, travel-time variations at tidal frequencies (about 50 ms peak to peak) agree well with predicted values, providing verification of the acoustic measurements as well as the tidal model. On the longest and northernmost acoustic paths, the time series of resolved ray travel times show an annual cycle peak-to-peak variation of about 1 s and other fluctuations caused by natural oceanic variability. An annual cycle is not evident in travel times from shorter acoustic paths in the eastern Pacific, though only one realization of the annual cycle is available. The low-pass-filtered travel times are estimated to an accuracy of about 10 ms. This travel-time uncertainty corresponds to errors in range- and depth-averaged temperature of only a few millidegrees, while the annual peak-to-peak variation in temperature averaged horizontally over the acoustic path and vertically over the upper 1 km of ocean is up to 0.5°C     

海洋水温垂直分布数据同化方法研究

以一维海洋水温模型为例,利用伴随法进行海洋观测数据同化试验,以便为水温的数值预报提供较准确的初始场.文中利用泛函的Gâteaux微分和Hilbert空间上伴随算子的概念讨论了连续的伴随模型的建立,并通过选择适当的差分格式离散伴随模型,使其保持连续时的伴随关系,同时给出了水温初始场最优化过程及相应的同化试验数值结果.