## 5 Results for AOI-1
### Natural Instabilities in AOI-1
#### 5.2.2. Peatlands  
Surface movements in different peatlands in AOI-1 have been detected through the PS-InSAR approach. The best example, marked as locality 'I' in Figure 7, is a 6 km\({}^{2}\) area of cut-over raised peat located north of Galway city (Figure 15a). Some 939 PSs, of which 606 are unstable, are distributed unevenly in the peat area. The majority occur in the central, intact part of the peat ecosystem, while only a few points are located along the harvested margins. Moreover, the central part of the peatland is generally moving upward at rates of up to 8.9 mm/year (e.g., point 1), while the marginal harvested areas are subsiding by up to \(-11.6\) mm/year (e.g., point 2). A transition between the two areas represented by stable points can also be observed.  
Figure 14. Field evidence of instability at localities along the Cliffs of Moher where motion was detected by PS-InSAR. (**a**) Top of the cliff at locality ‘I’, as seen from the south. Note person for scale. (**b**) The cliff face at locality ‘I’, as seen from the north. Note the fresh debris fan at the cliff base. Washed out by the ocean waves, the fine fraction of the fresh debris slope is seen as a sediment plume in the sea adjacent to the cliff base. (**c**) The talus slope on the north flank of the Hag’s Head promontory, locality ‘I’, as seen from the west. From the base of the talus slope, the cliff extends vertically a further \(\sim\)10 m down to the sea. (**d**) The talus slope on the south flank of the Hag’s Head promontory, locality ‘I’, as seen from the east.  
While some points (e.g., at locations (1) and (2)) have linear long-term displacement trends, others (e.g., at location (3)) display fluctuations that correlate with precipitation amount (Figure 16). Wetter periods correspond to uplift, while periods of drought correspond to subsidence. For example, the 38-day interval from 03 April 2017 to 11 May 2017 had an average rainfall of 0.21 mm that corresponds to a total lowering of 6 mm detected in five consecutive dates, from 11 April 2017 to 11 May 2017. During field reconnaissance in July 2018, we noted that the harvested areas were dry with tall, re-growing vegetation. Moving towards the center of the bog, water content increased, and white moss (Sphagnum) started to appear. The water table was around 20-40 cm below the surface near the bog center, as seen in cracks. At the center of the intact bog, was observed a slight change in vegetation given by taller leaved plants.  
Surface motions were also detected in a 1 km\({}^{2}\) area of blanket peatland in west Clare (Figure 15b), marked as locality 'g' in Figure 7. Out of 358 PSs, 324 are unstable. No consistent signs of uplift (only five isolated measured points) were found in this case. Instead, this peatland is dominantly subsiding at rates of up to \(-\)16 mm/year. Field reconnaissance again revealed that the areas of highest point density corresponded to unharvested areas dominated by Sphagnum moss, where peat cover over bedrock is thin (a few tens of cm) or even absent. Formerly harvested areas are now overgrown by dense deep vegetation cover (bracken) and yielded few to no PSs.  
Figure 15: Surface movement detected by PS-InSAR in peatlands in AOI-1. (**a**) Uplift and subsidence movements occurring over a raised peatland, denoted locality ‘f’ in Figure 7. To notice the different behavior of the reported displacements time series extracted (white circle) for the (1) intact (uplift) and (2) harvested (subsidence) peat areas. (**b**) Subsidence occurring in a blanket peatland, denoted locality ‘g’ in Figure 7. The white circle marks the location of the extracted displacement time series (4).