地表温度变化对GNSS连续运行基准站垂向形变影响研究

Research on Influence of Surface Temperature Change on VerticalDeformation of GNSS Continuously Operating Reference Station

利用实测地表温度数据,计算温度变化对GNSS基准站观测墩和基岩垂向形变的影响;联合大气负荷变化,综合分析温度变化对基准站垂向形变的影响规律。以新疆GNSS连续运行基准站数据为例,结果表明,温度变化对新疆GNSS连续运行基准站垂向影响的年周期项振幅为1.4~2.1 mm,半周年振幅为0.01~0.33 mm,周年项振幅占主要部分;垂向时间序列变化扣除温度变化影响后,RMS值平均减小0.55 mm,精度提高约9%;温度变化与大气负荷变化对垂向形变影响的趋势基本一致,呈现上半年增加、下半年下降,扣除两项影响后精度提高约13%。研究表明,温度和大气负荷变化均为基准站垂向位移周期性变化的重要影响因素。

We use measured surface temperature data to calculate the vertical deformation effect of temperature change on pillar and bedrock of GNSS reference station.Combining with the atmospheric load change,the influence of temperature change on vertical deformation of reference station is comprehensive analyzed.We use Xinjiang GNSS continuously operating reference station data as an example,the results show that the annual impact of temperature change on Xinjiang GNSS continuously operating reference station is 1.4-2.1 mm,and the half-annual amplitude is 0.01-0.33 mm.The annual amplitude accounts for the majority.When the vertical time series change minus the effect of temperature change,the average RMS value is reduced by 0.55 mm,and the accuracy is improved by about 9%.The effect of temperature change and atmospheric load on the vertical deformation is basically same,showing an increase in the first half of the year and a decrease in second half.At the same time,when the two effects are deducted,the accuracy is improved by about 13%.The research in this paper shows that the changes in temperature and atmospheric load are very important factors for the periodic displacement of reference station.