Publications des scientifiques de l'IRD

Cabre A., Rémy Dominique, Aguilar G., Carretier Sébastien, Riquelme R. (2020). Mapping rainstorm erosion associated with an individual storm from InSAR coherence loss validated by field evidence for the Atacama Desert. Earth Surface Processes and Landforms, 45 (9), 2091-2106. ISSN 0197-9337.

Titre du document
Mapping rainstorm erosion associated with an individual storm from InSAR coherence loss validated by field evidence for the Atacama Desert
Année de publication
2020
Type de document
Article référencé dans le Web of Science WOS:000529658900001
Auteurs
Cabre A., Rémy Dominique, Aguilar G., Carretier Sébastien, Riquelme R.
Source
Earth Surface Processes and Landforms, 2020, 45 (9), 2091-2106 ISSN 0197-9337
Extreme high-magnitude and low-frequency storm events in arid zones provide the necessary runoff to entrain sediments from source areas and therefore dictate the linkages between hillslopes and channels. Nevertheless, the erosive impact of large storms remains difficult to predict. Most of the uncertainty lies in the lack of topographic change maps associated with single hydro-meteorological events. Consequently, event-based erosion models are poorly constrained and their extrapolation over long time periods remains uncertain. In this study, a 15-month Sentinel-1A coherence time series, optical and field data are used to map the spatial patterns of erosion after the 5-day storm occurred on March 2015, in the Atacama Desert. The coherence change detection (CCD) analysis suggests that temporal loss of coherence is related to variations in soil moisture, while permanent loss of coherence is related to modification of soil texture by erosion and sedimentation. Importantly, permanent loss of coherence is more apparent on gentle rather than steeper slopes, likely reflecting differences in regolith cover and thickness. These findings can contradict the landscape models predicting higher erosion on steeper hillslopes. The CCD technique represents a promising tool for analysing and modelling sediment connectivity in arid areas, giving a clear picture of the relation between sediment sources and sink pathways.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Géologie et formations superficielles [064] ; Pédologie [068]
Description Géographique
CHILI ; ATACAMA
Localisation
Fonds IRD [F B010079035]
Identifiant IRD
fdi:010079035
Contact