New research from the University of Nottingham and Peatland Action has highlighted how satellites can be used to predict an area's landslide susceptibility.
The research team used interferometric synthetic aperture radar (InSAR) - a monitoring technique which uses radar imagery to measure ground movement - to improve the assessment of peat landslide susceptibility at 20 peatland sites across Scotland.
The technique helps by allowing the production of maps at a national scale to feed into restoration projects, providing surface motion data and allowing sites to be reviewed after restoration to see how it has affected their susceptibility to landslides.
Peat landslides - slides, flows and bog bursts - are a significant natural hazard particularly associated with areas of blanket peat where steeper slopes, complex topography and generally higher rates of landscape erosion are more likely to lead to peat instability.
Evaluating peat landslide susceptibility is made particularly difficult for a number of reasons, including a lack of information on local variations in the thickness of peat, poorly characterised geotechnical properties, and the unknown and complex internal structure and hydrology of the peat.
Current geotechnical approaches to landslide susceptibility assessment are complex, intensive and can be expensive to deploy at a large scale.
Although peat landslides are rare in Scotland, it's important to consider the risks when planning any peatland restoration project, with this new research helping with these plans.
The study, led by Professor David J Large from Nottingham's Department of Chemical and Environmental Engineering, looked at peatland sites across Scotland, from Shetland to Dumfries and Galloway.
The research – which uses satellite Earth observation data and was first tested over three large peat landslides in Ireland – found that there's a greater chance of movement in areas of natural drainage in the peat.
The study also established that a high range of 'bog breathing' – or up and down motion in the peat – doesn't indicate that a landslide will definitely occur. However, it does indicate areas that may be more susceptible to landslide.
Our method is ideal for rapidly screening large areas to identify where best to undertake more expensive geotechnical investigations. Potential application included not only peatland restoration but also wind energy developments on peat."
Following the study, Peatland ACTION will be looking in more detail at any areas identified as having 'very high' motion.
This study will also help to establish whether Earth observation data should be incorporated into peat landslide risk assessment procedures.
