地表质量负载对格陵兰岛区域GPS站点坐标时序特征的影响

选取ITRF2008框架下格陵兰岛区域12个GPS站2013年1月-2016年12月期间的日解坐标时间序列作为研究对象，并利用极大似然估计分析地表质量负载改正前后各站点的噪声特性、速度场及周期项振幅。结果表明：站点最优噪声模型主要为白噪声+幂律噪声与白噪声+闪烁噪声，地表质量负载形变修正GPS坐标时序后，明显增加U方向闪烁噪声的成分，平均降低其速度约0.36 mm/a，对水平方向影响较小；同时分别降低高程方向44.1%、14.2%的1 a项、0.5 a项振幅，相反，却增加了水平方向的周期项振幅。

The effect of surface mass loading on coordinate time series characteristics of GPS stations in Greenland region

Based on the daily coordinate time series of 12 GPS stations situated in the Greenland with the time span of period from January 2013 to December 2016 under the framework of ITRF2008,and the noise characteristics, velocity field and periodic term amplitude of each GPS coordinate time series before and after surface mass loading correction are analyzed by maximum likelihood estimation.The results show that the optimal noise model of most GPS coordinate time series is white noise+power law noise and white noise + flicker noise.After correcting GPS coordinate time series by surface mass loading deformation, the flicker noise in the up components is obviously increased,and the average velocity is reduced by about 0.36 mm/a. Compared with the vertical components, the surface mass loading correction has relatively minor effects on the horizontal components. At the same time, the amplitudes of the annual and semi-annual signals in the up componentsare reduced by 44.1% and 14.2% respectively.Whereas, the amplitudes of periodic terms in the horizontal components are increased.