Monitoring Dutch Peatland Subsidence Using InSAR – First Results

Actively monitoring ground motion is of the highest importance in The Netherlands, a country inwhich many of its regions lie below sea level. Water tables in the country have been managedfor centuries by using a system of dams, dikes and canals through which excess water can bepumped away to allow for the prevention of flooding, and for the reclamation of submerged land.However, the effects of centuries of active water management in the region have resulted insignificant land subsidence, and its effects are being felt as it is becoming a significant threat tothe future of the country as sea levels continue to rise [1].This has created the need to monitor land surface motion at large spatial scales with frequenttemporal sampling. While InSAR is a promising candidate for such a task, the technique oftensuffers from drastic losses of signal quality in the spring and summer months when used toproduce time series observations of peatlands. This significantly limits the effectiveness ofInSAR as a tool to monitor peatland surface dynamics [2,3,4].We present the preliminary results of peatland surface motion using a novel InSAR processingmethod which is designed to overcome the issues which have prevented its application overnorthern peatlands in the past [5]. This work is the first large scale analysis of the Dutch GreenHeart region made with InSAR, providing land surface motion time series data at the parcelscale for a 2000 km2 region with sub-weekly sampling over the period Jan. 2015 to Oct. 2023.Our presentation will briefly outline the results, validation efforts and the various challengesinvolved.References[1] G. Erkens, M. J. van der Meulen, and H. Middelkoop, “Double Trouble: Subsidence and CO2 Respiration Due to1,000 Years of Dutch Coastal Peatlands Cultivation,” Hydrogeology Journal, vol. 24, no. 3, pp. 551–568, 2016.[2] Y. Morishita and R. F. Hanssen, “Temporal decorrelation in L-, C-, and X-band satellite radar interferometry forpasture on drained peat soils,” IEEE Transactions on Geoscience and Remote Sensing, vol. 53, no. 2, pp. 1096–1104, 2015.[3] Y. Morishita and R. F. Hanssen, “Deformation parameter estimation in low coherence areas using a multisatelliteInSAR approach,” IEEE Transactions on Geoscience and Remote Sensing, vol. 53, no. 8, pp. 4275–4283, 2015.[4] L. Alshammari, D. J. Large, D. S. Boyd, A. Sowter, R. Anderson, R. Andersen, and S. Marsh, “Long-term peatlandcondition assessment via surface motion monitoring using the ISBAS DInSAR technique over the flow country,Scotland,” Remote Sensing, vol. 10, no. 7, 2018.[5] P. Conroy, S. A. N. van Diepen, F. J. van Leijen, and R. F. Hanssen, “Bridging loss-of-lock in InSAR time series ofdistributed scatterers,” IEEE Transactions on Geoscience and Remote Sensing, vol. 61, pp. 1–11, 2023