Experimental observations of the movement of desert dunes using unmanned aerial vehicles

Background/Question/Methods

Desert dunes offer unique geophysical interactions, and these aeolian dominant interactions occur over a significant portion of earth surfaces. There are multiple factors that determine the direction and shape of these dunes, which include sand availability and primary wind modes throughout the year. We pursued whether the movement of desert dunes can be accurately measured using an unmanned aerial vehicle (UAV) data from a structure-from-motion. To do so, three data sets total were collected in 2018, 2019, and 2021 of the Little Sahara dunes in northwest Oklahoma. To collect the imagery, a RGB camera was attached to a DJI Phantom 4 Pro UAV and flown along a set path. Using these images, a 3D model of the dunes was created using Agisoft Metashape for each year’s data set to output a digital elevation model (DEM). After acquiring the DEMs, they were analyzed and coordinated in ArcMap. Finally, using ENVI and the add-on CosiCorr, the movement of the dunes could be estimated and shown with a vector field.

Results/Conclusions

In spite of some variance between the years, the models were able to show the displacement of the dunes as they have moved throughout the year. Preliminary data shows displacement varied between 0 to 15 centimeters with the greatest displacements occurring along the boarder of the dunes. Our data indicates the UAV imagery can increase the ease of monitoring and tracking the movement of landmasses.