Global uniform chart datum(CD)surface construction is the basic upon which to realize various vertical datums transformation,and is of great importance for geospatial data expression under the same vertical datum.Gene...Global uniform chart datum(CD)surface construction is the basic upon which to realize various vertical datums transformation,and is of great importance for geospatial data expression under the same vertical datum.Generally,the CD level is computed by developing the function between tidal constituents’harmonic constants and time,i.e.,the lowest astronomical tide is taken as the lowest predicted tide level by adopting the major constituents over a 19-a period.The CD surface prescribed in China is the theoretical lowest tide(TLT)and is calculated using 13 tidal constituents,i.e.,short-period(Q_(1),O_(1),P_(1),K_(1),N_(2),M_(2),S_(2),K_(2),M_(4),MS_(4)and M_(6))and long-period(Sa and Ssa)tidal constituents.Although the accuracy in determining short-period tidal constituents has improved gradually,the long-period tide has not been studied thoroughly owing to nonstationary and temporal variations.Previous studies have intended to evaluate the effect of Sa and Ssa tides in the determination of the TLT level for the purpose of determining a more accurate CD surface for the China seas and adjacent waters.Here,the parameters of long-period tidal correction and long-period tidal correction rate were treated as the effect of both Sa and Ssa on the TLT,and the TOPEX/Poseidon and Jason series satellite altimetry data ranged from October 1992 to April 2022 were adopted to analyze the contribution of long-period tidal constituents.Results showed that the average long-period correction value is 10.10 cm(range from 8.57 cm to 14.98 cm),and that the average long-period tidal contribution rate is 14.56%(range from 9.09%to 23.97%)in the China seas and adjacent waters.Finally,data from 82 tide gauge station with at least a 1-a record of hourly observations were compared with satellite-derived result.We concluded that the long-period tidal contribution should not be neglected in TLT construction.Furthermore,to reduce tidal datum uncertainty,accurate extraction of long-period tidal constituents should receive closer attentions.展开更多
继在南极中山站建成我国南极首个永久性验潮站后,2012年1月在南极长城站又建成了我国南极第二个永久性验潮站。通过对长城站验潮站相关数据进行分析处理,得到了验潮基准系统的水准网平差结果和验潮仪零点标定结果,以及长城站附近海域海...继在南极中山站建成我国南极首个永久性验潮站后,2012年1月在南极长城站又建成了我国南极第二个永久性验潮站。通过对长城站验潮站相关数据进行分析处理,得到了验潮基准系统的水准网平差结果和验潮仪零点标定结果,以及长城站附近海域海洋潮汐170个分潮的调和常数,并据此进行了潮汐预报,同时分析了长城站潮汐余水位的变化特征,探讨了利用附近的Antarctic Base Prat验潮站的余水位改正长城站潮汐预报的可行性,结果表明使用Antarctic Base Prat验潮站余水位改正长城站潮汐预报,可以显著提高长城站验潮站潮汐预报的精度,余水位改正后2014时段的潮汐预报中误差为±3.42 cm,明显好于改正前的预报中误差±10.43 cm。展开更多
基金The National Natural Science Foundation of China under contract No.42104035the Basic Scientific Fund for National Public Research Institutes of China under contract No.2023Q05the Natural Science Foundation of Shandong Province under contract No.ZR2020QD087.
文摘Global uniform chart datum(CD)surface construction is the basic upon which to realize various vertical datums transformation,and is of great importance for geospatial data expression under the same vertical datum.Generally,the CD level is computed by developing the function between tidal constituents’harmonic constants and time,i.e.,the lowest astronomical tide is taken as the lowest predicted tide level by adopting the major constituents over a 19-a period.The CD surface prescribed in China is the theoretical lowest tide(TLT)and is calculated using 13 tidal constituents,i.e.,short-period(Q_(1),O_(1),P_(1),K_(1),N_(2),M_(2),S_(2),K_(2),M_(4),MS_(4)and M_(6))and long-period(Sa and Ssa)tidal constituents.Although the accuracy in determining short-period tidal constituents has improved gradually,the long-period tide has not been studied thoroughly owing to nonstationary and temporal variations.Previous studies have intended to evaluate the effect of Sa and Ssa tides in the determination of the TLT level for the purpose of determining a more accurate CD surface for the China seas and adjacent waters.Here,the parameters of long-period tidal correction and long-period tidal correction rate were treated as the effect of both Sa and Ssa on the TLT,and the TOPEX/Poseidon and Jason series satellite altimetry data ranged from October 1992 to April 2022 were adopted to analyze the contribution of long-period tidal constituents.Results showed that the average long-period correction value is 10.10 cm(range from 8.57 cm to 14.98 cm),and that the average long-period tidal contribution rate is 14.56%(range from 9.09%to 23.97%)in the China seas and adjacent waters.Finally,data from 82 tide gauge station with at least a 1-a record of hourly observations were compared with satellite-derived result.We concluded that the long-period tidal contribution should not be neglected in TLT construction.Furthermore,to reduce tidal datum uncertainty,accurate extraction of long-period tidal constituents should receive closer attentions.
文摘继在南极中山站建成我国南极首个永久性验潮站后,2012年1月在南极长城站又建成了我国南极第二个永久性验潮站。通过对长城站验潮站相关数据进行分析处理,得到了验潮基准系统的水准网平差结果和验潮仪零点标定结果,以及长城站附近海域海洋潮汐170个分潮的调和常数,并据此进行了潮汐预报,同时分析了长城站潮汐余水位的变化特征,探讨了利用附近的Antarctic Base Prat验潮站的余水位改正长城站潮汐预报的可行性,结果表明使用Antarctic Base Prat验潮站余水位改正长城站潮汐预报,可以显著提高长城站验潮站潮汐预报的精度,余水位改正后2014时段的潮汐预报中误差为±3.42 cm,明显好于改正前的预报中误差±10.43 cm。
