Spatio-temporal evolution of aeolian sand patterns in the Boulenouar Region, Mauritania: Insights from InSAR coherence and K-means Analysis

This study combines Interferometric Synthetic Aperture Radar (InSAR) techniques with Sentinel-1B data and NASA's MERRA-2 reanalysis meteorological data to monitor the annual spatiotemporal evolution of aeolian processes in the arid region of Boulenouar, northwest Mauritania. Analysis of 31 SAR images acquired between February 2020 and February 2021 identifies three key areas affected by wind activity: a vast field of mobile barkhan dunes, the town of Boulenouar, and the surrounding road and rail infrastructure. Unsupervised k-means classification of coherence images shows that 19.4\% of the dunes are highly active. The study indicates an annual erosion rate of 3.84\% to the north and west, accompanied by a sedimentation rate of 15.56\% along transport axes and around Boulenouar. Correlated with NASA meteorological data, the analysis shows that wind activity is most intense in spring and summer. This study highlights the potential of coupling Sentinel-1 InSAR data with meteorological data to finely map wind dynamics in desert environments.