基于GPS-IR的复杂寒区地表冻融状态监测研究

Surface Freezing-thawing Monitoring in Complex Cold Region Based on GPS-IR

针对复杂寒区地表冻融状态情况,基于GPS-IR(Global Positioning System-Interference Reflectometry)技术进行地表冻融状态监测精度研究。采用2017—2022年PBO(The Plate Boundary Observatory)GPS站点数据,结合SNOTEL气象站地表实测数据,充分考虑了复杂寒区地表积雪深度、土壤湿度和地表冻融状态对GPS(Global Positioning System)多路径观测值的影响,基于GPS-IR技术利用卫星反射信号来进行地表冻融状态监测。结果表明:在积雪深度和土壤湿度时间序列平稳的状态下,GPS-IR技术的冻融监测精度为90.63%,积雪深度和土壤湿度的波动都会导致监测精度下降。实验表明GPS-IR技术的监测精度会受到积雪深度和土壤湿度的影响,在地球物理参数小范围变化的情况下监测精度较好,对地表冻融状态响应敏感,是一种有效监测复杂寒区冻融特性的有效手段。

According to the situation of surface freezing-thawing state in complex cold regions,we studied the monitoring accuracy of surface freezing-thawing state based on GPS-IR technology.We used PBO GPS site data from 2017 to 2022 and SNOTEL meteorological in-situ data,considering the effects of snow depth,soil moisture and surface freezing-thawing process on GPS multipath observables,and based on GPS-IR technology,used the satellite reflected signal to monitor surface freezing-thawing status.The results indicate that the retrieval accuracy is 90.63%when the time series of snow depth and soil moisture keep stable,while the fluctuations of snow depth and soil moisture will both decrease the final retrieval accuracy.The soil freezing-thawing process detection is sensitive to the geophysical parameters,and can achieve a good accuracy as the other influence factors keep in a small variation range.