Area and volume quantification of Arctic thaw slumps using time-series of digital elevation models

Vast areas of the Arctic host ice-rich permafrost, which is becoming increasingly vulnerable to terrain-altering thermokarst in a warming climate. Among the most rapid and dramatic changes are retrogressive thaw slumps. These slumps evolve by a retreat of the slump headwall during the summer months, making their change visible by comparing digital elevation models over time. In this study we use digital elevation models generated from single-pass radar TanDEM-X observations to derive volume and area change rates for retrogressive thaw slumps. At least three observations in the timespan from 2011 to 2017 are available with a spatial resolution of about 12 meter and a height sensitivity of about 0.5-2 meter. Our study regions include regions in Northern Canada (Peel Plateau/Richardson Mountains, Mackenzie River Delta Uplands, Ellesmere Island), Alaska (Noatak Valley) and Siberia (Yamal, Gydan, Taymyr, Chukotka) covering an area of 220.000 km2 with a total number of 1853 thaw slumps.In this presentation we will focus on the area and volume change rate probability density functions of the mapped thaw slumps in these study areas. For landslides in temperate climate zones the area and volume change probability density function typically follow a distribution that can be characterized by three quantities: A rollover point defined as the peak in the distribution, a cutoff-point indicating the transition to a power law scaling for large landslides and the exponential beta coefficient of this power law. Here we will show that thaw slumps across the arctic follow indeed such a distribution and that the obtained values for the rollover, cutoff and beta coefficient can be used to distinguish between regions. Furthermore we will elaborate on possible reason why arctic thaw slumps can be described by such probability density functions as well as analyzing the differences between regions. This characterization can be useful to further improve our understanding of thaw slump initiation, the investigation of the drivers of their evolution as well as for modeling future thaw slump activity.

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Delineating northern peatlands using Sentinel-1 time series and terrain indices from local and regional digital elevation models

Remote Sensing of Environment ◽

10.1016/j.rse.2019.111252 ◽

2019 ◽

Vol 231 ◽

pp. 111252 ◽

Cited By ~ 5

Author(s):

Martin Karlson ◽

Magnus Gålfalk ◽

Patrick Crill ◽

Philippe Bousquet ◽

Marielle Saunois ◽

...

Keyword(s):

Time Series ◽

Digital Elevation Models ◽

Digital Elevation ◽

Northern Peatlands ◽

Terrain Indices

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Detection of seasonal cycles of erosion processes in a black marl gully from a time series of high-resolution digital elevation models (DEMs)

Earth Surface Dynamics ◽

10.5194/esurf-4-781-2016 ◽

2016 ◽

Vol 4 (4) ◽

pp. 781-798 ◽

Cited By ~ 10

Author(s):

Jacques Bechet ◽

Julien Duc ◽

Alexandre Loye ◽

Michel Jaboyedoff ◽

Nicolle Mathys ◽

...

Keyword(s):

Time Series ◽

High Resolution ◽

Digital Elevation Models ◽

Slope Angle ◽

Laser Scanner ◽

Research Station ◽

Runoff Generation ◽

Erosion Processes ◽

Antecedent Precipitation ◽

Digital Elevation

Abstract. The Roubine catchment located in the experimental research station of Draix-Bléone (south French Alps) is situated in Callovo-Oxfordian black marls, a lithology particularly prone to erosion and weathering processes. For 30 years, this small watershed (0.13 ha) has been monitored for analysing hillslope processes on the scale of elementary gullies. Since 2007, surface changes have been monitored by comparing high-resolution digital elevation models (HRDEMs) produced from terrestrial laser scanner (TLS). The objectives are (1) to detect and (2) to quantify the sediment production and the evolution of the gully morphology in terms of sediment availability/transport capacity vs. rainfall and runoff generation. Time series of TLS observations have been acquired periodically based on the seasonal runoff activity with a very high point cloud density ensuring a resolution of the digital elevation model (DEM) on the centimetre scale. The topographic changes over a time span of 2 years are analysed. Quantitative analyses of the seasonal erosion activity and of the sediment fluxes show and confirm that during winter, loose regolith is created by mechanical weathering, and it is eroded and accumulates in the rills and gullies. Because of limited rainfall intensity in spring, part of the material is transported in the main gullies, which are assumed to be a transport-limited erosion system. In the late spring and summer the rainfall intensities increase, allowing the regolith, weathered and accumulated in the gullies and rills during the earlier seasons, to be washed out. Later in the year the catchment acts as a sediment-limited system because no more loose regolith is available. One interesting result is the fact that in the gullies the erosion–deposition processes are more active around the slope angle value of 35°, which probably indicates a behaviour close to dry granular material. It is also observed that there exist thresholds for the rainfall events that are able to trigger significant erosion; they are above 9 mm rainfall or of an intensity of more than 1 mm min−1, values which can vary if antecedent precipitation is significant within the last 5 days.This study improves knowledge of the spatial distribution of erosion seasonality in badlands and demonstrates the potential of careful 3-D high-resolution topography using TLS to improve the understanding of erosive processes.

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Decennial Geomorphic Transport From Archived Time Series Digital Elevation Models: A Cookbook for Tropical and Alpine Environments

IEEE Geoscience and Remote Sensing Magazine ◽

10.1109/mgrs.2021.3121370 ◽

2021 ◽

pp. 2-17

Author(s):

Antoine Lucas ◽

Gayer Eric

Keyword(s):

Time Series ◽

Digital Elevation Models ◽

Digital Elevation ◽

Alpine Environments

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Comparison of Gridded DEMs by Buffering

Remote Sensing ◽

10.3390/rs13153002 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3002

Author(s):

Francisco Javier Ariza-López ◽

Juan Francisco Reinoso-Gordo

Keyword(s):

Quality Control ◽

Complex Analysis ◽

Accuracy Assessment ◽

Digital Elevation Models ◽

Distribution Functions ◽

Control Techniques ◽

Digital Elevation ◽

Quality Control Techniques ◽

Area And Volume

Comparing two digital elevation models (DEMs), S1 (reference) and S2 (product), in order to get the S2 quality, has usually been performed on sampled points. However, it seems more natural, as we propose, comparing both DEMs using 2.5D surfaces: applying a buffer to S1 (single buffer method, SBM) or to both S1 and S2 (double buffer method, DBM). The SBM and DBM approaches have been used in lines accuracy assessment and, in this paper, we generalize them to a DEM surface, so that more area of the S2 surface (in the case of the SBM), or the area and volume (in the case of the DBM) that are involved, more similarly are S1 and S2. The results obtained show that across both methods, SBM recognizes the presence of outliers and vertical bias while DBM allows a richer and more complex analysis based on voxel intersection. Both methods facilitate creating observed distribution functions that eliminate the need for the hypothesis of normality on discrepancies and allow the application of quality control techniques based on proportions. We consider that the SBM is more suitable when the S1 accuracy is much greater than that of S2 and DBM is preferred when the accuracy of S1 and S2 are approximately equal.

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