潮汐调和常数的变化趋势研究

潮汐调和常数具有随时间变化的特性,以某一长期验潮站44年的观测数据为样本,研究分析了在短期、中期和长期观测时段下潮汐调和常数的变化规律,计算出各分潮调和常数的平均值、最大互差及中误差的变化量级。研究表明,较短时间的观测资料得出的各分潮调和常数存在着较大的变动误差,但随着观测时间的增长,其误差量级呈逐渐减小并且逐步稳定的变化趋势。建议采用调和常数计算理论最低潮面时,宜选定19年作为观测周期,以消除分潮调和常数的误差影响,满足高精度海洋测深基准面的稳定和统一。

Study on the Variety Trend of Tidal Harmonic Constants

Tidal harmonic constant has time-varying characteristics.Based on the 44-years-observation-data of one long-term tidal station,this paper analyzed variation rule of tidal harmonic constants,figured out their average,observation error,maximum mutual error and the mean error of sub-tidal harmonic constant.It shown that the sub-tidal harmonic constant derived from shorter observational data contained a big change error,but with the observation time increased,the error magnitude was gradually reduced,showed a gradual steady trend.This paper proposed to select 19 years as the observation period to calculate the Lowest Normal Low Water,in order to eliminate the error effects of sub-tidal harmonic constants and to meet the stability and unity of highprecision bathymetry datum.