Ash sedimentation by fingering and sediment thermals below wind-affected volcanic plumes

My PhD was part of a larger ongoing collaboration between UBC and the Université Clermont Auvergne (UCA), France. My supervisor, Dr. Mark Jellinek (UBC), is an expert in geological fluid mechanics and explosive eruption dynamics and my co-supervisor, Dr. Franck Donnadieu (UCA), is a Doppler radar specialist who has pioneered the adaptation of focused beam Doppler radar methods to the study of volcanic plumes and ash clouds. In 2020 we published a paper led by Dr. Valentin Freret-Lorgeril that studies how ash settles from ash clouds erupted from Mt. Stromboli, Italy. We find that the ambient wind enhances the formation of ash-laden fingers evolving into sediment thermals descending from the base of Strombolian ash clouds, thereby causing ash to reach the ground faster than it would if it settled individually, which is the standard model for ash settling. Our model is not limited to relatively small eruptions and can be applied to larger eruptions where the effect of a crosswind has a significant effect on the dynamics of rising ash plumes and spreading ash clouds.