平均海面传递方法的比较与选择

给出了常用平均海面传递方法的假设条件.以中国沿岸典型验潮站为例,统计不同同步时长下各传递方法的精度.统计分析表明,同步时长在7d内时应慎用回归分析法;最小二乘拟合法的假设条件缺乏相关的理论支持,只适用于潮差变化较小的区域;同步改正法在同步7d时基本能保证极值误差在10cm内,而同步15d与同步30d的精度相当,能达到厘米级.基于分析结果给出了传递方法的选择建议,为提高中短期验潮站的平均海面确定精度提供了依据.     

2013年《海洋测绘》论文综述

针对2013年《海洋测绘》刊载的论文情况,从海洋测绘学科发展角度,通过对各专业论文发表情况的统计分析,对海洋测量、遥感影像处理、海图制图等专业的发展现状,进行了归纳总结和简要评述。旨在为广大测绘工作者提供参考。     

A preliminary investigation on the scaling behaviour of rainfall observed in two different climates

Abstract

The problem of transformation of rainfall data from one scale to another has been gaining considerable importance in recent years. Though the application of the concept of fractal theory, in the studies conducted thus far, nearly unanimously points at the possibility of such a transformation, the suitability of the theory to the highly variable rainfall in time and space has very often been questioned. A preliminary attempt is made herein to address this issue by investigating the existence of temporal scaling behaviour in rainfall data observed in two different climatic regions: (a) a subtropical climatic region (Leaf River basin, Mississippi, USA) and (b) an equatorial climatic region (Singapore). Rainfall data of three different resolutions, six-hourly, daily, and weekly, observed over a period of 25 years, are investigated. A mono- or simple-scaling method (box dimension method) is employed. The results achieved for the different data sets clearly indicate the existence of temporal scaling in rainfall observed in the two regions, an encouraging news on the suitability of fractal theory in understanding and modelling the rainfall process. However, the insufficiency of a single dimension to characterize the rainfall behaviour is realized, as the dimension depends on the rainfall intensity level, which, in turn, may be related to the rainfall generating mechanisms. A comparison of the box-dimension results obtained for data of different resolutions, from each of the regions, seems to indicate a possible connection between them, a prospect of tremendous practical importance. Another interesting observation is the similarity between the box dimension results obtained for rainfall data from Leaf River basin and Singapore, but this is also clearly related to the intensity level. The dependence of the dimension on the intensity threshold suggests the use of a multi-dimensional fractal approach, where the process is characterized by more than one dimension (or a dimension function) instead of one single dimension. On the basis of the present results, some potential areas for further study are identified.     

晚新生代金沙江形成时代与过程研究

在多次的野外考察和充分的室内分析的基础上,对金沙江地区河谷层状地貌系列和断陷盆地相关沉积进行了分析,系统地研究了金沙江自晚新生代以来的形成和演化。晚新生代金沙江水系的形成和演化经历了四个阶段：①３．４０ＭａＢ．Ｐ之前,为高原面形成期间的古水系阶段;②３．４０～２．００±０．２０ＭａＢ．Ｐ,为金沙江水系孕育阶段;③２．００±０．２０～１．５４±０．１７８ＭａＢ．Ｐ,为金沙江水系调整阶段;④１．５４±０．１７８ＭａＢ．Ｐ以来为现代金沙江水系形成与发展阶段     

The hydrographic features of the ocean region around the Ryukyu Islands during summer of 1997

IwnODUCTIONTheECSandthePacificOceanareseparaedbytheRyUkyUIs1andshavingthreermnPasSagesforwaerexchangbebeenthesetWowateboies.TheKewshioenterstheECS~ghthestraiteastofTaiwanIslandandflowsbacktothePacificOceantboghTugalaStrait.TheOkinawIsland-MiyakoIslandstralt(KeanTrench,withdepth>1opm)allowalopqUanityofwaerexchangebetweentheECSandthePacifico-cean(YUanandPan,l994).InvestigationdatashowsthatthehydIDgraPhicfeatUresoftheoceanregionarOUntheRyukyUIslandsareverycomPlicated.Somcold…     

南极普里兹湾及其邻近海域的水文结构特征和底层水的来源

利用中国第九次南大洋考察中南极普里兹湾及其邻近海域的CTD资料,分析研究了调查海域的水文结构特征及其该区南极底层水(AABW)的来源.研究结果表明,在研究海域,深水洋区近表层流由西向东流,而在普里兹湾内存在一个气旋型涡.水文结构中最明显的海洋学特征是:(1)绕极深层水(CDW)的涌升现象明显,涌升最强的位置是麦克罗伯逊地以北海域,最明显的深度是50～200m层,暖水涌升将冬季冷水分隔成南北两部分,并在其中形成孤立的暖水块;(2)陆缘水边界明显,这是绕极深层水与南极冷水之间形成的锋面,一般处在次表层水中,大致位于64°～66°S之间;(3)存在着双跃层结构.观测期间,普里兹湾以北探水海域存在着南极底层水,其来源可能有二:一为当地形成,二为源于威德尔海和罗斯海.     

Hydrographic Structure and Transport of Intermediate Water in the Kuroshio Region off the Boso Peninsula, Japan

Hydrographic structure and transport of intermediate water were observed in the Kuroshio region south of Japan, focusing on the 26.6–27.5σ_θ density in six cruises from May 1998 through September 2001. In the section off the Boso Peninsula where the Kuroshio exfoliates eastward, the intermediate water was clearly clustered into three groups meridionally composed of the coastal water, the Kuroshio water and the offshore water. Compared with the Kuroshio water characterized by warm, salty water transported by the Kuroshio, the coastal and offshore waters significantly degenerated due to mixing with cold, fresh waters originated from the subarctic region: the former was affected by alongshore spread of the coastal Oyashio and the latter by direct intrusion of the new North Pacific Intermediate Water (NPIW) into the southern side of the Kuroshio current axis. Particularly the offshore water showed higher apparent oxygen utilization (AOU) in layers deeper than 26.9σ_θ while it showed lower AOU in layers shallower than 26.9σ_θ, which indicated that colder, fresher and higher AOU water was distributed on the southeastern side of the Kuroshio in deeper layers. In May 1998, the Oyashio-Kuroshio mixing ratio was estimated to be typically 2:8 for the offshore water on the assumption of isopycnal mixing. Moreover, northeastward volume transport of the Kuroshio water was obtained from geostrophic velocity fields adjusted to lowered acoustic Doppler current profiler (LADCP) data to yield 6.1 Sv at 26.6–26.9σ_θ and 11.8 Sv at 26.9–27.5 σ_θ. This revised version was published online in July 2006 with corrections to the Cover Date.     

S-101电子海图产品规范解析

针对S-101电子海图产品规范尚未发布正式版本的现状,该文介绍了S-57数字海道测量数据传输标准发展的局限性与S-100海道测量数据模型的体系结构特点,探讨了S-101标准中的详细内容,对S-101标准中要素描述目录、复合属性、信息类型、不依比例尺变化要素、曲线等新的要素和特征进行了分析,并对S-101标准的发展进行了展望。     

基于分形维的底质分类

概述了目前主要的基于侧扫声纳图像的海底分类方法,重点介绍了分形维在侧扫声图海底分类中的应用及图像分形维的几种估计方法,包括Peleg法、微分盒计数、移位微分盒计数和标准差盒计数法,并给出利用上述方法获得的三种典型底质侧扫声图的分形维计算结果。