| 09 Mar 2026
SPAMS10: InSAR-derived soil motion parameters to model relative peat surface elevation changes
Abstract. Peat subsidence poses a significant challenge to long-term land and environmental stability. Field monitoring with extensometers reveals variability in relative surface elevation changes, which are then modeled using simple parameterization for the motion of soils (SPAMS). To extend the spatial scale of monitoring, Interferometric Synthetic Aperture Radar (InSAR) time series are used. InSAR-derived SPAMS parameters provide meaningful displacement models that can describe peat subsidence and dynamics with a limited set of parameters. In this study, we publish the SPAMS10 dataset, which includes both physical and statistical parameters, along with additional contextual information at the parcel level. This dataset promotes data sharing among stakeholders, shifting products from InSAR-based relative elevation estimates to InSAR-derived displacement model parameters. These parameters enable detailed and reproducible analyses of peat subsidence. The dataset is available through the 4TU.ResearchData repository: https://doi.org/10.4121/dfbe9109-d058-4a64-a5b4-1cc9d9a5f836 (Lumban-Gaol et al., 2025) and is distributed under a Creative Commons Attribution 4.0 International (CC BY 4.0) license.
Comments pasted here and in attached PDF
REVIEW - Earth System Science Data
Title: SPAMS10: InSAR-derived soil motion parameters to model relative peat surface elevation changes
Author(s): Yustisi Lumban-Gaol and Ramon Hanssen
MS No.: essd-2026-143, MS type: Data description article
General comments
Overall, the paper presents a useful data set and the methods by which the data are generated are well described. This is well structured and laid out in a logical fashion. There are, however, several general areas where the paper could be improved:
Specific comments
Title – I would recommend including the word ‘dataset’ alongside SPAMS10, so it is clear this is the data and not the SPAMS model. This is the practice throughout the majority of the paper so I would also do it here. I was initially confused whether this was the data or the model.
L1 – What is meant by ‘environmental stability’ this is a very vague term please say something more specific.
L5 – Make it clear why it is ‘SPAMS10’ – 10 parameters.
L6 – please state clear what you mean by physical and statistical parameters and contextual information. This is too descriptive and does not tell us anything.
L6 – What is meant by ‘parcel’ – this is not clear at this stage in the paper so should be given context (adda few words in brackets?).
L8 – You state ‘These parameters enable detailed and reproducible analyses of peat subsidence.’ You need to give some statistics of the actual data and some error estimates (reproducibility) to support this statement. Inclusion of quantitative results would better illustrate the utility of the dataset.
L16 – Conclude this sentence with some suitable references.
L16-18 - Link the specific references to the particular challenges don’t just list at the end of the sentence.
L33-35 - Add references to support this statement.
L37 – You define SPAMS10 in terms of 10 parameters yet on L5 you say there were “a limited set of parameters”. Ten parameters do not appear to be a limited set – can you word this better. Or do you really mean there are three main parameters and one constant (integration time). I think this could be better explained and worded.
L41-42 – It is unclear how you arrived at an integration time of 69 days and why it is so ‘constant’. Some physical explanation of this is needed.
L47 – 49 - How realistic is the “ assumption that conditions such as soil stratigraphy, groundwater management, and land use remain constant over time”. Do you mean over the 7 years of the data? If you described the field area better (see earlier comments) then you would be in a stronger position to justify this assumption.
L51 – Define an ‘agricultural parcel’ – do you mean a field or unit of similar land use? Also see earlier comments about the description of the field area.
Figure 1 - How representative is one extensometer site at the eastern margin of the study area. You should address this point in the text to assure readers it is representative.
L85 - You state “while the displacement signals are assumed to be correlated in time with limited spatial correlation”. Why do you assume limited spatial correlation - this is not always the case with subsidence over wide areas? How can you justify this assumption?
L88-89 – See earlier comments - define ‘parcel’ and provide some statistics on the size distribution of these parcels.
L92-93 - It is stated ” In peatlands, we assume that surface elevation changes are driven by environmental (meteorological) conditions.” – If this is the case then give some context for the seven-year period over which subsidence was measured.
L103-104 - You provide some insights into the agriculture of the area (ploughing events) but because you have not provided a fuller description of the area these events are hard to contextualise.
L134-135 - You say “ We group parcels by soil type and water table zone and include only grassland parcels. The contextual grouping reduces the number of segments, thereby aiming to reduce segment shift noise. The group is formed if there are at least 15 and no more than 50 parcels. “ This fundamentally affects the dataset but the background to this is not really explained in detail or justified. By how much are the segments are reduced? Why are only grassland parcels included? How are the group limits (15-50) determined?
L162-167 - The results and data could be much better explained. See suggestions above.
Figure 2 (page 8) – Add additional information to the Figure caption. Plots (a) and (b) explain scaling factor vales. Also state whether the data shown in the Figure is averaged over the 7-year observation period?
Figure 3 (Page 9) – Explain why the length of record differs for the extensometer period compared to the whole data series and why there are no recent observations 2022-2023. It is also stated in the caption “ InSAR-based relative elevation estimates
(red dots), and the SPAMS model (blue line) showing similar agreement levels” but this should be quantified.
Technical corrections
L51 – You do not need to say, ‘see Figure 1.’ You can just bracket it (Figure1).
L114 (bottom of page 5) – You provide one footnote. This is the only one in the document and is at odds with the general style. You should remove it and add the relevant text to the main body of the paper.
L270 – ‘Van Asselen@ should be ‘van Asselen’
L273 – Subscripts for CO2 and CH4