PhD Studentship: Advancing Multi-Mission Satellite Radar for Monitoring Permafrost Degradation and Erosion in a Changing Arctic

The Arctic is warming rapidly, causing widespread permafrost thaw and associated ground deformation, instability and erosion. Monitoring these changes across vast and remote Arctic regions is challenging, yet understanding how the ground responds to permafrost degradation is increasingly important for assessing environmental change and risks to infrastructure and communities. Satellite radar interferometry (InSAR) provides a powerful means of measuring ground deformation from space. However, individual satellite missions have important limitations.

Sentinel-1 operates at C-band and can lose measurement coherence over vegetated and rapidly changing surfaces, while the newly available NISAR mission provides L-band observations that can maintain greater coherence over many natural surfaces and have different sensitivity to vegetation and surface properties. The missions also have different acquisition geometries, temporal sampling and measurement uncertainties. Rather than treating these observations independently, this PhD will investigate how their complementary information can be combined to produce more complete and reliable measurements of ground deformation. The project will develop a new multi-mission InSAR framework integrating Sentinel-1 C-band and NISAR L-band observations.

Research will investigate the effects of wavelength-dependent scattering, differences in spatial and temporal sampling, viewing geometry and measurement uncertainty on the integration of observations from the two missions. Importantly, the complementary viewing geometries of the two missions, with Sentinel-1 operating in a right looking configuration and NISAR providing left-looking observations, offer an opportunity to better constrain the north–south deformation component, which is poorly resolved by either mission independently due to their near-polar orbits. New joint inversion approaches will therefore be developed to exploit these complementary geometries alongside the heterogeneous multi-frequency observations to improve estimates of temporally evolving three dimensional ground deformation. Arctic permafrost environments will provide a demanding real-world testbed for developing and evaluating these methods.

Satellite-derived deformation will be investigated in relation to active-layer thickness, permafrost degradation and progressive ground instability, including riverbank and coastal erosion. Through collaboration with Montana State University, the project will benefit from complementary geotechnical expertise and access to extensive in Engineering and Physical Sciences Research Council Doctoral Landscape Award situ active-layer-thickness observations for validation and interpretation.

The project will also offer the opportunity for a research visit to Montana State University, providing experience within an international, interdisciplinary research environment. The student will work with large Earth observation datasets and high-performance computing, including the COMET-LiCSAR processing framework and JASMIN, the UK’s data analysis facility for environmental science. The project will provide advanced training in satellite radar remote sensing, InSAR, inverse methods, scientific programming and environmental data analysis. Although demonstrated in the Arctic, the resulting multi-mission methodology will have wider potential for monitoring landslides, subsidence, volcanic deformation and other geohazards.