IMCLASS – A USER-TAILORED MACHINE LEARNING IMAGE CLASSIFICATION CHAIN FOR CHANGE DETECTION OR LANDCOVER MAPPING

The recent calving of the Astrolabe glacier in November 2021 presents an opportunity to better understand the processes leading to ice fracturing. Optical satellite imagery is used to retrieve the calving cycle of the glacier ice tongue and to measure the ice velocity and strain rates in order to document fracture evolution. We observed that the presence of sea ice for consecutive years has favored the glacier extension but failed to inhibit the growth of fractures that accelerated in June 2021.

Landslides and flash floods are rainfall-induced processes that often co-occur and interact, generally very quickly. In mountainous cloud-covered environments, determining when these processes occur remains challenging. We propose a regional methodology using open-access satellite radar images that allow for the timing of landslide and flash floods events, in the contrasting landscapes of tropical Africa, with an accuracy of up to a few days. The methodology shows potential for transferability.

Rockfall simulations are often performed to make sure infrastructure is safe. For that purpose, rockfall trajectory data are needed to calibrate the simulation models. In this paper, an affordable, flexible, and efficient trajectory reconstruction method is proposed. The method is tested by reconstructing trajectories from a full-scale rockfall experiment involving 2670 kg rocks and a flexible barrier. The results highlight improvements in precision and accuracy of the proposed method.

Natural disasters such as landslides and rock falls are mostly difficult to study because of the impossibility of making in situ measurements due to their destructive nature and spontaneous occurrence. Seismology is able to record the occurrence of such events from a distance and in real time. In this study, we show that using a machine learning approach, the mass and velocity of rockfalls can be estimated from the seismic signal they generate.

Seismic sources generated by the deformation of unstable slopes are diverse in terms of signal properties and mechanisms. Standardized catalogues of landslide endogenous seismicity can help understanding the physical processes controlling slope dynamics. We propose a generic typology of seismic sources based on the analysis of signals recorded at various instrumented slopes. We demonstrate that the seismic signals present similar features at different sites and discuss their mechanical sources.