Impacts associated with aeolian remobilisation of volcanic ash: are they so different from those related to mineral dust?

FORTE, PABLO; DOMINGUEZ, L.; BONADONNA, C.; JARVIS, P.; BRAN, D.

Simposio; Blowing South: Southern Hemisphere Dust Sysmposium; 2021

Explosive volcanic eruptions typically eject large amounts of ash into the atmosphere that eventually accumulate on the Earth?s surface. However, the cycle of volcanic ash does not stop there. When specific conditions are met, ash can be remobilised by wind and re-entrained into the atmosphere for years to decades and even thousands of years after an eruption has ended. Although the occurrence of this phenomenon was reported in the first half of the 20th century, little attention has been devoted to it because of its complexity and, today, our knowledge is still incomplete. Nonetheless, the recent eruptions of Eyjafjallajökull (2010, Iceland) and Cordón Caulle (2011, Chile) volcanoes have highlighted again the impact of remobilised ash on communities and the environment, generating a renewed interest among the volcanological community. The Argentinian Patagonia is one of the three main geographical regions in the world, together with Alaska and Iceland, where this phenomenon has been reported. Remobilisation of ash associated with deposits from the eruptions of Hudson (1991), Chaitén (2008), Cordón Caulle (2011) and Calbuco (2015) volcanoes have been observed during and after the eruption. In this work, we review the impacts associated with the aeolian remobilisation of these deposits in the Argentinian Patagonia, as well as the methodologies employed to assess them. In addition, we compare these impacts with those reported in the existing literature for mineral dust in order to establish similarities and differences between them. We expect this work to promote discussion on how volcanic ash and mineral dust researchers can collaborate to raise awareness around these hazardous processes and together contribute to improving strategies to mitigate the associated impacts.