共查询到10条相似文献,搜索用时 93 毫秒
1.
2.
Akihiko Morimoto 《Journal of Oceanography》2009,65(4):477-485
The magnitude and geographical distribution of the error in the Archiving, Validation and Interpretation of Satellite Oceanographic
data (AVISO) altimetry data associated with tidal correction around Asian marginal seas has been revealed. The errors were
evaluated by harmonic analysis of the AVISO corrected sea surface heights data (CorSSH). Errors of more than 15 cm of tidal
correction were recognized in the western and northern parts of the Yellow Sea, Celebes Sea, Kuril Islands, and the northwestern
part of the Okhotsk Sea. It was found that the CorSSH and sea level anomaly (SLA) data downloaded from the AVISO are not available
for direct use in those marginal seas. To reduce the tidal correction error, the harmonic constants calculated from the latest
tide model and regional tide model were applied as the tidal correction of the Altimetry data. The tidal errors in the Yellow
Sea and the northwestern part of the Okhotsk Sea were reduced by approximately 20 cm and 10 cm, respectively. Root mean square
differences between the harmonic constants derived from tide models and those derived from altimetry data were calculated.
The root mean square differences were large in the Yellow and the Okhotsk Seas. Root sum squares for four principal tidal
constituents in the Yellow and East China Seas and Okhotsk Sea were 7.72 cm and 8.36 cm, respectively. 相似文献
3.
随着卫星高度计资料的不断丰富,通过对卫星高度计所得潮汐调和常数进行插值或拟合得到潮汐同潮图成为可能。本文拟对T/P(TOPEX/POSEIDON)、Jason-1和Jason-2卫星高度计数据进行分析,得到南海区域星下观测点处四个主要分潮(M2、S2、K1和O1分潮)的调和常数,进而利用双调和样条插值方法对其进行插值,获取南海同潮图。首先,以1992~2016年T/P和Jason卫星高度计所得海面高度数据为基础,利用调和分析方法计算了南海星下观测点处M2、S2、K1和O1四个主要分潮的调和常数,并与40个验潮站数据进行了对比,最大矢量均差为4.99cm,说明分析所得调和常数与利用验潮站资料提取的调和常数的误差较小。进而采用双调和样条插值方法对星下点调和常数进行插值,得到了南海四个主要分潮的同潮图,所得结果与全球潮汐模型TPXO7.2模式结果的矢量均差分别为4.69、2.46、3.13和2.42 cm,与141个验潮站处观测结果的矢量均差分别为22.59、10.26、10.24和8.51 cm。此外,插值所得四个主要分潮的无潮点位置与前人研究结果相近。上述实验结果表明:利用双调和样条插值方法对卫星高度计所得调和常数进行插值能够获取较为准确的同潮图。 相似文献
4.
5.
Distribution of 9 Principal Tidal Constituents and Tide Prediction for the East China Sea 总被引:5,自引:0,他引:5
QIAN Chengchun 《中国海洋工程》2000,14(4):541-548
By use of the hydrodynamic model,the harmonic constants of 8 principal tidal constituents(Q_1,O_1,P_1,K_1,N_2,M_2,S_2andK_2)are obtained for the East China Sea,and the harmonic constant ofS_a is calculated by two-dimensional interpolation.The calculated results agree well with the observed dataaround the sea.The harmonic constants can be used to predict the tide in the East China Sea.The cotidalcharts of the 9 tidal constituents reveal their distribution. 相似文献
6.
The scarcity of tide gauges in a global scale and the variability of the tidal levels along contiguous coasts mainly due to changing hydrographic conditions make the determination of tidal levels, especially of the Mean Sea Level, not an easy task. Determination of such levels with a precision of about 10 cm, necessary for most coastal engineering works, is usually based on records of temporary tide gauges or on geomorphological techniques. In this paper we present an alternative approach permitting to accurately identify tidal levels with a precision suitable for civil engineering applications based on biological observations on rocky shores, including breakwaters and quays. More specifically, we present evidence that the biological zonation, i.e. the distribution of coastal species in well-defined sub-horizontal belts, is practically insensitive to seasonal and other small-scale fluctuations of the sea level and is clearly related to certain levels, mostly the Mean Low Water (MLW). This approach, somewhat similar to what has been used in the past (for instance for the determination of the geodetic vertical datum in the Republic of Venice, Italy, till approximately AD 1800), permits direct determination of the Mean Sea Level or of other tidal levels on the basis of biological observations without statistical analyses of tide-gauge records with an accuracy of 5–10 cm, especially in microtidal, low-energy coasts. 相似文献
7.
《African Journal of Marine Science》2013,35(3):321-330
A review is provided of the African sea level dataset, which is limited not only in size, especially given the great length of the African coastline, but also in quality. The review is undertaken primarily from Permanent Service for Mean Sea Level (PSMSL) and Global Sea Level Observing System (GLOSS) perspectives, but the conclusions on the need for major new investments in sea level infrastructure are undoubtedly the same as would be arrived at through any other approach. Stations to be installed as part of the Ocean Data and Information Network for Africa (ODINAfrica) programme are described and a survey of currently existing and planned sea level stations in Africa is presented, together with information on where data for existing stations may be found. 相似文献
8.
The constant and harmonic parts of the global ocean tide are modeled by up to nine major tidal constituents, namely, S2, M2,
N2, K1, P1, O1, Mf, Mm, and Ssa. Our computations start with the Fourier sine and cosine series expansion for the tidal constituents,
including the constant Mean Sea Level (MSL). Although the frequencies of the tidal constituents are considered known, the
coefficients of the sine and cosine functions are assumed to be unknown. Subsequently, the coefficients of the sine and cosine
functions, as well as the constant part of the Fourier expansion, were expanded into spherical harmonics up to degree and
order n, where n corresponds to the number of linearly independent spherical harmonic base functions needed to model the tidal constituents,
determined via independent columns of the Gram matrix. The unknown coefficients of the spherical harmonic expansions are computed
using sea level observations within cycles #1–#350 of the TOPEX/Poseidon satellite altimetry over 11 years of its mission.
A set of orthonormal base functions was generated for the marine areas covered by TOPEX/Poseidon observations from the spherical
harmonics using a Gram-Schmidt orthogonalization process. These were used for modeling the dominant tidal constituents. The
computed models based on orthonormal base functions for the nine tidal constituents and the constant part of the Fourier expansion,
were tested numerically for their validity and accuracy, proving centimeter accuracy. 相似文献
9.
长江口海图深度基准面换算关系研究 总被引:10,自引:0,他引:10
长江口不同时期的海图采用的深度基准面不一样 ,为充分利用诸多历史海图资料 ,需要了解历史海图深度基准面之间的关系。本文介绍了海图理论深度基准面 (前苏联弗拉基米斯基的低潮面 )的推算方法 ,用Matlab语言实现了对海图理论深度基准面的人机交互式计算。利用 1977年实测潮位资料计算获得的调和常数 ,计算了长江口 10个验潮站的深度基准面 ,探讨了不同深度基准面之间的换算关系 相似文献
10.
In this paper, tidal data of 19 years were analysed to obtain the harmonic constants of 472 constituents; yearly variations of the harmonic constants of some constituents for 19 years were also examined.We have also derived the formulae of response analysis by using another approach, and calculated 161 response weights of astronomical tides, solar radiational tides and nonlinear tides for 10 stations. Some significant results were obtained. 相似文献