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111.
A multi-subwaveform parametric retracker of the radar satellite altimetric waveform and recovery of gravity anomalies over coastal oceans 总被引:3,自引:0,他引:3
HWANG CheinWay 《中国科学:地球科学(英文版)》2010,(4)
The quality of satellite radar altimetric data is very important in studies of geodesy,geophysics,and oceanography.Over coastal oceans,altimeter waveforms are contaminated by the terrain and physical environments so that the accuracy of altimeter data is lower than that over open oceans.Here we develop a new multi-subwaveform parametric retracker(MSPR) to improve the quality of altimeter data for the recovery of gravity anomaly in coastal oceans.The least squares collocation method is used to recover the residual gravity anomaly over the coastal water from altimetric data.The waveform data records from Geosat/GM around Taiwan Island are practically retracked with MSPR.When compared with the Taiwan geoid height,the results retracked by MSPR are more accurate than those retracked by the well-known β-5-parmeter method and from the geophysical data records(GDRs).The gravity anomalies over Taiwan coastal waters are calculated from the retracked altimeter data with the least squares collocation.When we compared gravity anomalies computed using altimeter GDRs with the ship-borne gravity data over Taiwan coastal ocean,we found that the results from retracked data are more accurate than those from GDRs. 相似文献
112.
中国天文学会天文学名词审定委员会 《天文学进展》2009,27(2)
中国天文学会名词审定委员会从1985年起开始在<天文学进展>发表天文学名词的推荐译名,到2008年已公布15批共2431个名词.现再推荐第16批105个名词,其中大多数是近年出现的天文学新词.希望读者在使用过程中对译名提出改进意见. 相似文献
113.
汶川地震前后的气象异常 总被引:1,自引:0,他引:1
有研究认为局地气象异常与地震之间存在着一定的相关性,那么震惊中外的汶川大地震前后有没有气象异常呢?应用NCEP再分析资料,以1988~2007年20年间局地气象要素的平均值和标准偏差为基准,通过构建气象异常指数对2008年5月12日汶川发生的大地震前后的日平均气温、日最高气温、日最低气温、日平均降水强度和日平均气压等5项气象要素指标的异常状况进行了分析,结果表明在地震前2个月的时间内有异常状况出现,并且其变化幅度和持续时间都比较长,在地震过后这些异常并未立即消失;从5项气象要素异常空间分异来看,汶川是气象异常的中心地带,表征了汶川地震与局地气象之间存在着一定的相关性。尽管气象异常是否是地震发生的必然前兆尚待进一步考证,但出现在汶川特大地震前后的气象异常再次给我们一个提示,即气象异常与地震的关系值得深入研究。 相似文献
114.
115.
夏季台湾暖流的水文化学特性及其对东海赤潮高发区影响的初步探讨 总被引:7,自引:1,他引:6
依据2006年夏季对东海区水文化学数据的现场调查, 对台湾暖流的水文化学特性进行了初步分析, 并对台湾暖流自身的水文化学特性对东海赤潮高发区的影响进行了初步探讨。结果表明, 夏季, 台湾暖流水具有台湾海峡水和黑潮次表层涌升水两个来源, 分别构成台湾暖流的表层水和深层水。通过亚硝酸盐含量的多少能够对表层水和深层水进行明显的区分。此外, 通过对台湾暖流水文特征的分析, 发现夏季台湾暖流在浙江沿海出现的上升流给赤潮生物提供了适宜的温度。并通过对台湾暖流的营养盐含量进行分析, 发现相对于硝酸盐含量, 台湾暖流含有较高的磷酸盐浓度, 能够缓解海区“过剩氮”导致的磷限制。 相似文献
116.
通过考察全球海洋环流数值模型以及TOPEX/Poseidon海洋测高数据,得到结论:1997/1998年后的部分J2异常变化可能来自海洋环流变化导致的质量重新分布,具体地说是太平洋环流变化导致的从高纬地区向低纬地区的质量迁移. 本工作表明来自于海洋内部温盐效应的变化对J2异常变化有重要贡献,进一步证实了卫星激光测距资料所得结果的可靠性. 相似文献
117.
推导并建立了块体的两种弹性运动方程:块体的整体旋转与均匀应变方程和块体的整体旋转与线性应变方程. 应用统计学原理,使用西域、青藏和华北块体上的GPS站速度数据,对这两种弹性运动方程与刚体运动方程模拟块体站速度的无偏性和有效性进行了统计检验. 检验结果表明,块体的整体旋转与线性应变方程是描述块体运动的最优模型. 将中国大陆划分为10个块体,应用块体的整体旋转与线性应变方程和块体上的GPS站速度估计了各个块体上的旋转与应变参数,按照1°×1°的间距计算了中国大陆及周边地区上1005个点的应变参数,分析了中国大陆及周边地区应变场的基本特征. 用本文方法得到的主压应变方向与地质学方法和测震学方法得到的主压应力轴方向具有很好的一致性(华南块体除外). 相似文献
118.
LI Chunlai ZUO Wei LIU Jianjun OUYANG Ziyuan National Astronomical Observatories Chinese Academy of Sciences Beijing Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Graduate School Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(5):1090-1093
Space debris, here referring to all non-operating orbital objects, has steadily increased in number so that it has become a potential barrier to the exploration of space. The ever-increasing number of space debris pieces in space has created an increasingly threatening hazard to all on-the-orbit spacecraft, and all future space exploration activities have to be designed and operated with respect to the increasing threat posed by space debris. Generally, space debris is classified as large, medium and small debris pieces based on their sizes. The large debris piece is easily catalogued, but medium to small debris pieces are very difficult to track and also quite different in damage mechanisms from the large ones. In this paper, a scheme of chemical classification of space debris is developed. In our scheme, the first-order classification is employed to divide space debris into two groups: natural 相似文献
119.
ZUO Wei LI Chunlai OUYANG Ziyuan LIU Jianjun XU TaoNational Astronomical Observatories Chinese Academy of Sciences Beijing Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Graduate School Chinese Academy of Sciences Beijing 《《地质学报》英文版》2004,78(5):1094-1103
It is essential to build a modern information management system to store and manage data of our circumlunar explorer in order to realize the scientific objectives. It is difficult for an information system based on traditional distributed technology to communicate information and work together among heterogeneous systems in order to meet the new requirement of Internet development. XML and Web Services, because of their open standards and self-containing properties, have changed the mode of information organization and data management. Now they can provide a good solution for building an open, extendable, and compatible information management system, and facilitate interchanging and transferring of data among heterogeneous systems. On the basis of the three-tiered browse/server architectures and the Oracle 9i Database as an information storage platform, we have designed and implemented a data archiving and retrieval system for the circumlunar explorer-LUNARINFO. We have also 相似文献
120.
LIU Guoping OUYANG Ziyuan LI Chunlai LIU Jianfeng National Astronomical Observatories Chinese Academy of Sciences Beijing Peking University of Aeronautics Astronautics Beijing 《《地质学报》英文版》2004,78(5):1104-1108
The data acquisition stations and the data processing center of the Science and Application Center for Lunar and Deep-space Exploration (SACLuDE) are located at different geographical sites. They respectively have their own local networks and interconnect with each other through access to the core data network. This paper describes the clock drift in the computer and other networked devices building up the infrastructure of the above local networks. The network time variance of the stochastic model is also estimated. The poor precision of network synchronization will bring about potential hazards to the network operation and application running in the networks, which is clarified in the present paper. At the end of the paper, a cost-effective and feasible solution is proposed based on the Global Position System (GPS) and the Network Time Protocol (NTP). 相似文献