Editorial Foreword

Cold and arid regions cover the majority of the earth surface. Cold regions are characterized by low temperatures, whereas arid regions are lack of water, thus some unique landscapes such as glacier, frozen ground, desert and oasis are formed and developed under the particular physical, chemical and biological processes in these regions. These raise a series of scientific questions to be solved urgently in relation to the ecosystem productivity, biodiversity, stability and living environments of these     

评估滨海湿地应对海平面上升的脆弱性的研究范式

滨海湿地是海陆交界的生态过渡带,也是对气候变化极为敏感的、脆弱的生态系统,海平面上升对全球滨海湿地构成了严重威胁.为了精确预测未来海平面加速上升背景下滨海湿地的变化趋势,有必要深入开展滨海湿地应对海平面上升的脆弱性评估研究.概述了评估滨海湿地应对海平面上升的脆弱性的研究范式,评估过程包括4个步骤:确定滨海湿地的高程资本...     

A New Sensitivity Analysis Approach Using Conditional Nonlinear Optimal Perturbations and Its Preliminary Application

Simulations and predictions using numerical models show considerable uncertainties, and parameter uncertainty is one of the most important sources. It is impractical to improve the simulation and prediction abilities by reducing the uncertainties of all parameters. Therefore, identifying the sensitive parameters or parameter combinations is crucial. This study proposes a novel approach: conditional nonlinear optimal perturbations sensitivity analysis(CNOPSA) method. The CNOPSA method fully consi...     

叠前深度域偏移成像技术及其应用

根据“西部煤炭资源高精度三维地震勘探技术”项目中对国内外各种深度域偏移成像方法和特点的调研成果．对各类深度域成像的算法和特点进行了总结,指出不同深度域成像算法选取原则主要依据构造复杂程度和横向速度变化情况。结合克希霍夫叠前三维深度域偏移模块说明深度域偏移原理和工作流程,并以实例说明叠前深度域成像能够解决因第四系地层厚度剧烈变化造成的下覆煤层赋存形态被扭曲、深度误差大、断层平面位置不准确等问题。该实例中,叠前深度域成像划分的煤层深度比时间域偏移剖面解释结果向下移动40多m,钻探结果证实其解释的煤层深度和断层位置比较准确。     

空间内插方法比较

空间内插可以分为几何方法、统计方法、空间统计方法、函数方法、随机模拟方法、物理模型模拟方法和综合方法。介绍了每一种方法的适用范围、算法和优缺点。指出没有绝对最优的空间内插方法,必须对数据进行空间探索分析,根据数据的特点,选择最优方法;同时,应对内插结果做严格的检验。开发通用空间内插软件、智能化内插以及加强相关基础研究将是空间内插研究的重点。     

Numerical study for specifying the major origin of low salinity water associated with <Emphasis Type="Italic">Chattonella</Emphasis> (Raphidophyceae) blooms in Tachibana Bay,Japan

In both 2009 and 2010, massive Chattonella blooms occurred in Tachibana Bay. Observation results show that high cell densities of Chattonella were distributed in the central area of Tachibana Bay with low salinity water. Model results indicate that the low salinity water originated from the Ariake Sea and intruded into Tachibana Bay during the northerly or weak winds. It is suggested that low salinity water was mainly discharged from the northern area of the Ariake Sea. Northerly wind enhanced the horizontal advection of the low salinity water intruding into Tachibana Bay originating from the northern area of the Ariake Sea.     

S-101与S-57分类编码对比分析(一):要素

地理要素的分类编码是人类认知地理信息世界的成果,也是人类对地理信息世界再认知的入口和关键。在海洋地理信息领域,S-101数据标准即将替代现行S-57 ENC标准,分类编码方案也将会相应改变。先对S-57到S-101的要素变化内容进行整体描述,再从地理要素、元要素、新增类型等三方面内容,对新旧两套分类编码中的要素内容进行对比分析,可为涉海人员消化吸收新标准提供一定的参考。     

声源定位算法的精度分析

针对国家靶场测量落点坐标测试手段存在局限性的问题,该文提出基于时延估计的声源定位算法,给出影响该算法定位精度的几个因素和传感器阵列的几种布站方式,并对各种布站方式的定位误差进行了仿真计算,通过仿真分析了在不同的布站方式下声波的传播速度误差和时间差测量误差对定位精度的影响。结果表明:采用声波定位技术测量落点坐标精度可满足指标要求;合理布设传感器阵列能够提高定位精度。     

Seasonal Variability in Circulation Pattern and Residence Time of Suo-Nada

The development and evolution of the persistent counterclockwise circulation in Suo-Nada have been studied in detail using a three-dimensional numerical model. The realistic circulation has been reproduced from the monthly climatological fields of salinity, temperature along the open boundary, wind, heat flux and buoyancy input from twenty-two major rivers surrounding the basin. The seasonal variation of fresh-water discharge from the rivers proved to be the most important forcing mechanism driving the circulation. The expansion and contraction of coastal low salinity water well corresponded with the development of counterclockwise circulation from spring to summer and dissipation from autumn to winter. The circulation was found to be vertically homogenous and quasi-barotropic. However, confined along the coastal zone is an estuarine flow (i.e., oppositely directed currents in the upper and lower layers) whose horizontal dimension conforms to the period of maximum buoyancy flux from the rivers. This indicates that the flow pattern in Suo-Nada can be separated into two distinct regions where the relative dominance of estuarine circulation plays a significant role. Furthermore, the monthly water exchange capacity for autonomous purification of the basin has been evaluated from the average residence time of conservative material based on the calculated current field. It is demonstrated that the kinetic energy of the basin is directly responsible in promoting water exchange in Suo-Nada. This revised version was published online in August 2006 with corrections to the Cover Date.