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Monitoring Slow-moving Landslides Using Satellite Radar and Open-source Tools (2025)

We investigate a slow-moving landslide in southern Taiwan using satellite radar data. By applying a technique called Persistent Scatterer Interferometry (PSI), we can detect very small ground movements over time with millimeter-level precision. Using five years of satellite observations (2018–2023), we find that the slope is moving slowly—only a few millimeters per year in both horizontal and vertical directions. We confirm these results with field measurements. Our study shows that combining satellite monitoring with open-source tools provides an effective and low-cost way to track landslides, helping improve hazard assessment and early warning in mountainous areas.

Assessing Decadal Sediment Erosion Rates: Insights from Improved DEMs of Differencing (2024)

This study examines sediment erosion in Taiwan's Zhoukou River Basin over the past 30 years, focusing on the impact of extreme rainfall. Traditional methods measure erosion over different time scales, but we used a unique approach for decade-long calculations with global and regional digital elevation models (DEMs). Our new method, applying Fourier analysis, reduces vertical bias in DEMs. Spectral analysis helps correct vertical offsets. Erosion rates calculated through DEMs of Difference (DoD) show a significant drop in sediment export from 1990-2010 to 2011-2020 due to reduced extreme rainfall. The denudation rate decreased from 14.19 mm/yr to 10.46 mm/yr in the Zhoukou River Basin. Our method effectively estimates sediment transport rates using underutilized DEMs.

Tracking Slow Landslide Movements with Optimized MTInSAR Workflow (2023)

This study focuses on detecting and monitoring slow-moving landslides in Taiwan using a sophisticated radar technique. Identifying over 2500 pre-existing landslides is crucial for assessing their activity, especially before typhoon seasons. The proposed method, "multi-snap2stamps," effectively analyzes nine slow-moving landslides, revealing seasonal patterns in two sites and accelerated movement in one. The study showcases the potential of the method for large-scale landslide detection and monitoring.

Tatun Volcanic System: Thermal Patterns and Earthquake Correlation (2023)

Satellite-detected land surface temperature (LST) and seismic records are used to study the volcanic activity of Tatun Volcanic Group. Analyzing four decades of LST and three decades of earthquake magnitude data reveals a correlation between LST trends and energy released from volcanic earthquakes, validating the connection between surface temperatures and volcanic activity.

Satellite Study: Thermal Patterns at Kueishantao Volcano, Taiwan (2023)

This research investigates the geothermal state of Kueishantao (KST) volcano in Taiwan using satellite-observed land surface temperature (LST). Analyzing LST anomalies from 1999 to 2022, the study reveals increasing temperatures in the southeast, correlating with potential magma reservoirs. The non-linear thermal pattern suggests dynamic subsurface activity, providing insights for geothermal resource management.

Tectonic Uplift in Fansipan and Tule Mountains, Northern Vietnam (2022)

The high elevations of Fansipan and Tule mountain ranges in northern Vietnam, adjacent to the Red River Fault, are influenced by active fault systems. Field and DEM data, along with geomorphic analyses, reveal potential normal and strike-slip faults, suggesting recent movements dominated by strike-slip and normal faulting. Extensional tectonics, particularly isostatic rebound, are proposed mechanisms for sustaining mountain elevations despite monsoon-driven weathering.

Seasonal Surface Fluctuation of a Slow-moving Landslide Detected by Multitemporal Interferometry (MTI) on the Huafan University Campus, Northern Taiwan (2021)

A long-term landslide on the Huafan University campus in Taiwan, observed since 1990, lacks reliable monitoring data post-2018 due to equipment maintenance issues. This study employs multitemporal interferometry (MTI) using Sentinel-1 SAR images from 2014–2019 to monitor the landslide. MTI reveals consistent slow-moving areas with previous studies, indicating gravity-induced deformation and seasonal surface fluctuations linked to precipitation. This technique compensates for the lack of data and aids in evaluating and monitoring landslides for potential early warnings.

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(M. Sc. Thesis) Improving Geologic Maps with LiDAR DEM: Yuli Coastal Range (2021)

(Master thesis, 2021: Chao, Po-Lien) Using high-resolution DEM derived from LiDAR in Taiwan's Coastal Range, this study overcame challenges in geologic mapping caused by dense vegetation and steep terrain. The mapping method successfully identified features in both igneous and sedimentary rock, revealing new structures like shear zones, faults, and monoclines. The results, including a 1:50000 geologic map and profiles, showcase the potential of this approach for geological studies and engineering applications.