顾及SLEL的GNSS垂向坐标时间序列非线性变化研究OA

To address the significant nonlinear variations in GNSS vertical coordinate time series caused by environmental loading,this study selected 103 continuous GNSS stations in Europe from 2013 to 2023 and,in addition to the conventional corrections for hydrological loading,non-tidal atmospheric loading,and non-tidal oceanic loading,further introduced sea level loading as a global mass-conservation term to systematically investigate its correction effect on vertical coordinate time series.Annual and semi-annual signals were estimated using the least-squares method,and the correction performance was evaluated in terms of amplitude reduction rates and RMS variations.The results show that the three conventional environmental loading components reduce the mean annual amplitude by 49.39%and the mean semi-annual amplitude by 13.12%.After further introducing sea level loading,the annual and semi-annual amplitudes are additionally reduced by 6.37%and 2.17%,respectively.Although this actual calculation sea level loading does not lead to an obvious improvement in RMS,it can further explain the periodic variations in GNSS vertical coordinate time series.Incorporating sea level loading into environmental loading corrections helps provide a more complete characterization of the nonlinear variations in GNSS vertical coordinate time series.