###### Abstract  
Reservoir bank landslides are a frequent phenomenon, and the stability of these landslides is affected by two essential factors: rainfall and reservoir level changes. Studying the response patterns of reservoir bank landslide movements to these variables is crucial in preventing their occurrence and mitigating their effects. To this end, this study employed 103 European Space Agency (ESA) Copernicus Sentinel-1 images and the SBAS-InSAR (small baseline subset interferometric synthetic aperture radar) technique to obtain a time series of the Guobu slope deformation from September 2015 to December 2019. The Guobu slope showed significant toppling damage. The satellite line of sight (LOS) detected a maximum subsidence rate of \(-447\) mm/y (the negative sign indicates movement away from the satellite, i.e., subsidence) in the upper section of the slope. Subsequently, three wavelet tools were used to quantitatively analyze the effect of rainfall and reservoir water level on the deformation of the Guobu slope. The results demonstrate a positive correlation between rainfall and the deformation of the Guobu slope. Moreover, the deformation lags behind the rainfall by approximately 70 days. In contrast, the reservoir water level and the deformation of the Guobu slope exhibit an inverse relationship. The deformation of the leading edge of the slope body lags behind the reservoir level by approximately 19 days, while the middle and upper sections of the slope body, which have the most significant rate of variability, lag by about 80 days. Among these factors, rainfall plays a dominant role in the deformation of the Guobu slope, while reservoir levels play a synergistic role. The findings of this study highlight the importance of monitoring and understanding the impact of changes in rainfall and reservoir water levels on the stability of reservoir bank landslides. This understanding is crucial in preventing the occurrence of such landslides and minimizing their impact. The use of remote sensing techniques, together with wavelet analysis, enables the accurate and timely monitoring of the deformation of the Guobu slope, providing valuable insights for disaster warnings and disaster prevention and reduction efforts. SBAS-InSAR; time series deformation; rainfall; reservoir water level; wavelet analysis +
Footnote †: journal:  
Reservoir began filling in 2003, the reservoir water level has been raised from 69 m to 175 m ASL (above sea level), and the water level has fluctuated annually between about 145 and 175 m ASL from 2008 to the present, during which a large number of landslides have been induced, such as the Qianjiangping landslide [7], the Shuping landslide [8] and the Muyubao landslide [9]. There have been 4429 geological hazards in the TGRA from Yichang to Jiangjin along the Yangtze River. Among them, 4256 were landslides and rock avalanches, with a total volume of about 4.24 billion m\({}^{3}\)[10]. Meanwhile, many scholars have found good agreement between the slow movement of landslides and seasonal rainfall [11; 12; 13; 14]. Therefore, detecting and monitoring the moving bank slopes, evaluating the magnitude of bank slope movement, and analyzing the internal relationship between landslide movement and hydrological factors are of great significance to ensuring the safe operation of hydropower projects. Landslide deformation is the most intuitive and effective means of characterization of the evolution of landslides, and reveals the inherent risk of landslides [12]. Therefore, monitoring surface deformation can provide critical information for detecting potential geological hazards such as landslides. Interferometry Synthetic Aperture Radar (InSAR) is an emerging technology for regional surface monitoring.