Proximity to active volcanoes enhances glacier velocity

Volcanic heating is predicted by theory to affect the velocity of nearby glaciers. However, conclusive studies on a large scale are lacking. Here, we conduct a global comparison of the velocities of glaciers near active volcanoes (i.e. within 5 km) and those located elsewhere (> 5 km from an active volcano). Our findings show that, when considered over an annual scale (e.g. 2017-2018) and controlling for other factors, glaciers near volcanoes flow 46% faster than those located elsewhere (based on median values). This finding strongly suggests that volcanic heating impacts glacier velocity at a global scale, and supports the idea that glacier velocity monitoring could be a valuable indirect tool to help volcano monitoring and eruption prediction, particularly where volcanic heating (and therefore subglacial melt) intensifies months or years prior to eruptions.