A New Methodology for Incorporating Tide Gauge Data in Sea Surface Topography Models   总被引：1，自引：0，他引：1  

J. C. Iliffe  M. K. Ziebart  J. F. Turner 《Marine Geodesy》2007,30(4):271-296

As part of the Vertical Offshore Reference Frames (VORF) project sponsored by the U. K. Hydrographic Office, a new model for Sea Surface Topography (SST) around the British Isles has been developed. For offshore areas (greater than 30 km from the coast), this model is largely derived from satellite altimetry. However, its accuracy and level of detail have been enhanced in coastal areas by the inclusion of not only the 60 PSMSL tide gauges with long-term records around the coasts of the United Kingdom and Ireland but also some 385 gauges established at different epochs and for different observation spans by the U. K. Admiralty. All tide gauge data were brought into a common reference frame by a combination of datum models and direct GPS observations, but a more significant challenge was to bring all short-term sea level observations to an unbiased value at a common epoch. This was achieved through developing a spatial-temporal correlation model for the variations in mean sea level around the British Isles, which in turn meant that gauges with long-term observation spans could be used as control points to improve the accuracy of Admiralty gauges. It is demonstrated that the latter can contribute point observations of mean sea level (MSL) with a precision of 0.078 m. A combination of least squares collocation and interpolation was developed to merge the coastal point and offshore gridded data sets, with particular algorithms having to be developed for different configurations of coastal topology. The resulting model of sea surface topography is shown to present a smooth transition from inshore coastal areas to offshore zones. Further benefits of the techniques developed include an enhanced methodology for detecting datum discontinuities at permanent tide gauges.  相似文献   

Unintended and perverse consequences of ignoring linkages in fisheries systems     

Degnbol  Poul; McCay  Bonnie J. 《ICES Journal of Marine Science》2007,64(4):793-797

  相似文献   

Assessing the population size of the European storm petrel (Hydrobates pelagicus) using spatial autocorrelation between counts from segments of criss-cross ship transects     

van der Meer  Jaap; Leopold  Mardik F. 《ICES Journal of Marine Science》1995,52(5):809-818

  相似文献   

On the geologic structure of the Explora Escarpment (Weddell Sea,Antarctica) revealed by satellite and Shipboard data evaluation     

Ute Christina Herzfeld  Arnold L. Brodscholl 《Marine Geophysical Researches》1994,16(5):325-345

Bathymetric, gravity, and magnetic data from Antarctic expeditions with RV POLARSTERN and satellite altimeter data from the Geosat Geodetic Mission are analysed using methods from geostatistics and geophysical inverse theory.The Explora Escarpment represents the edge between the Antarctic Continental Shelf and the Weddell Abyssal Plain. It is an important link in the reconstruction of Gondwana breakup, but a feature as large as the 2000 m deep Wegener Canyon was only discovered in 1984, when extensive bathymetric, gravimetric, and magnetic surveys with RV POLARSTERN began.Geostatistics, the theory of regionalized variables, is applied to integrate dense surveys of Wegener Canyon and sparse observations in adjacent areas into maps with full coverage of the 230 km by 330 km area at 10°–20° W/70°–72° S. The resultant highresolution bathymetric and gravity maps reveal detailed structures of the Explora Escarpment. Using geophysical inversion, the gravity terrain effect is calculated. Satellite data are used for their better coverage, but have much lower resolution. Nevertheless, the structures of Wegener Canyon and other more prominent features appear with surprisingly good correlation also in the Geosat altimeter data. While it was initially supposed that Wegener Canyon is purely an erosional structure, the magnetic map now provides evidence of the canyon's tectonic origin.  相似文献   

Modelling morphological processes in the vicinity of shore-parallel breakwaters     

Julio A. Zyserman  Hakeem K. Johnson 《Coastal Engineering》2002,45(3-4)

  相似文献   

State Estimation of the North Pacific Ocean by a Four-Dimensional Variational Data Assimilation Experiment   总被引：1，自引：0，他引：1  

Toshiyuki Awaji  Shuhei Masuda  Yoichi Ishikawa  Nozomi Sugiura  Takahiro Toyoda  Tomohiro Nakamura 《Journal of Oceanography》2003,59(6):931-943

A four-dimensional variational data assimilation system has been applied to an experiment to describe the dynamic state of the North Pacific Ocean. A synthesis of available observational records and a sophisticated ocean general circulation model produces a dynamically consistent dataset, which, in contrast to the nudging approach, provides realistic features of the seasonally-varying ocean circulation with no artificial sources/sinks for temperature and salinity fields. This new dataset enables us to estimate heat and water mass transports in addition to the qualification of water mass formation and movement processes. A sensitivity experiment on our assimilation system reveals that the origin of the North Pacific Intermediate Water can be traced back to the Sea of Okhotsk and the Bering Sea in the subarctic region and to the subtropical Kuroshio region further south. These results demonstrate that our data assimilation system is a very powerful tool for the identification and characterization of ocean variabilities and for our understanding of the dynamic state of ocean circulation. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

基于GIS数据仓库的激光单分子海洋油气化探数据可视化处理          下载免费PDF全文

李谷祺  杨作升  刘?? 展  张?? 勇  初晓璐 《海洋科学》2007,31(2):13-16

采用基于地理信息系统(GIS)的数据仓库技术,以激光单分子海洋油气化探数据处理与评价作为数据仓库主题,实现了激光单分子海洋油气化探数据的可视化处理。将可视化处理分为4个步骤:数据预处理、异常背景分析、异常分析、异常综合评价;使用MAPX、DELPHI等软件研制开发了相应的可视化软件模块。通过对渤海湾盆地某测区实测的甲苯化探数据的处理,验证了所开发技术的实用性。  相似文献   

渤海区域地质信息管理系统数据库设计方案   总被引：1，自引：0，他引：1  

张勇  杨作升  刘展  乔淑卿 《海岸工程》2002,21(4):1-5

数据库是GIS的基础。以渤海区域地质信息管理系统数据库为例，阐述了基于GIS的海洋地学管理信息系统中数据库的组织方法，及所包括空间数据库与属性数据库数据分类、分层方案，命名及编码规则，以及二者之间的联接。  相似文献   

GeoSwath相干多波束系统原始数据的解析     

许可求  张叶春  王平 《热带海洋学报》2007,26(4):37-42

通过分析GeoAcoustics公司的GeoSwath相干多波束系统的二进制原始文件结构,使用VC 6.0设计出各传感器字段的数据结构,并编程实现相干多波束数据的提取和图形可视化。该技术方法对于GeoSwath系统多波束数据的提取和分析处理有参考意义。  相似文献   

Spatial Variation in the Structure of Kelp Forest Communities Along a Wave Exposure Gradient     

Christopher  Harrold  James  Watanabe Susan  Lisin 《Marine Ecology》1988,9(2):131-156

Abstract. Four sites were sampled in kelp (Macrocysiis pyrifera) forests occupying rocky bottom habitats along a wave exposure gradient in central California. Consistent betwecn-site differences were found in the three major structural elements - the surface canopy, the undcrstory assemblage, and the ground cover/turf assemblage - of kelp forest communities. Macrocysiis pyrifera was found at all four sites. Nereucyslis tuelkeana only at the most exposed site. The understory kelps Laminaria setchellii and Pterygopltora californica were also characteristic of exposed sites. Articulated coralline algae were more abundant at exposed sites than protected, while fleshy red algae showed the opposite pattern. All four study sites were located along 8.5 km of coastline, and thus were assumed to have available to them the same species pool for colonization. The substrate composition was the same and the amount of unconsolidated substrate was similar at all four sites. We suggest that exposure to wave-generated water motion, through its influence on the surface canopy and therefore on the amount of light reaching the bottom, is responsible for these between-site differences.  相似文献