In the vast expanse of Angola, a groundbreaking study led by Dr. Andreas Braun from the Institute of Geography at the University of Tübingen is reshaping our understanding of digital elevation models (DEMs) derived from Synthetic Aperture Radar (SAR) interferometry. As the energy sector increasingly relies on precise topographical data for exploration and infrastructure development, Braun’s research offers critical insights into the role of temporal baselines in DEM accuracy, with significant implications for commercial applications.
The study, published in the *Geoscientific Instrumentation, Methods and Data Systems* (translated as *Geoscientific Instruments, Methods and Data Systems*), evaluates the vertical accuracy of DEMs generated from interferometric image pairs acquired during the calibration phase of the upcoming Sentinel-1C satellite, set to launch in late 2025. By analyzing image pairs with temporal baselines of 1, 6, and 12 days, Braun and his team have uncovered crucial data that could revolutionize how the energy sector approaches topographic mapping.
“Our findings indicate that the temporal baseline between SAR image acquisitions plays a pivotal role in the accuracy of DEMs,” Braun explains. “The 1-day pair showed remarkable accuracy with an RMSE of approximately 14.7 meters, while the 6-day pair exhibited moderate degradation with an RMSE of about 16.4 meters. However, the 12-day pair experienced a pronounced loss of accuracy, with an RMSE of approximately 49.4 meters, primarily due to coherence loss in vegetated areas.”
This research is particularly relevant for the energy sector, where precise elevation data is essential for site selection, pipeline routing, and environmental impact assessments. “Accurate DEMs are the backbone of many geospatial applications, from hydrological modeling to environmental monitoring,” Braun notes. “Understanding the limitations and capabilities of SAR interferometry is crucial for optimizing these models and ensuring reliable data for commercial applications.”
The study also highlights the challenges posed by different land cover types and slopes. Coherence and elevation error distributions revealed clear dependencies, with lower performance in forested and steep terrain. “These findings should be regarded as indicative due to the limited number of suitable image pairs during the calibration phase,” Braun cautions. “However, this early assessment provides an important reference point for future Sentinel-1A/C DEM generation studies, informing both methodological refinement and application planning in SAR-based topographic mapping.”
As the energy sector continues to evolve, the insights from Braun’s research could shape the development of more accurate and reliable DEMs, ultimately enhancing the efficiency and sustainability of energy projects. “This research is a stepping stone towards better understanding the nuances of SAR interferometry,” Braun concludes. “It’s an exciting time for the field, and we’re eager to see how these findings will influence future developments.”
With the launch of Sentinel-1C on the horizon, the energy sector can look forward to more precise and reliable topographical data, thanks to the pioneering work of Dr. Andreas Braun and his team. As the industry continues to push the boundaries of exploration and infrastructure development, the role of SAR interferometry in providing accurate DEMs cannot be overstated. This research not only highlights the importance of temporal baselines but also paves the way for future advancements in the field, ensuring that the energy sector has the tools it needs to navigate the complexities of the natural landscape with greater precision and confidence.