1. Nordic Volcanological Centre (NordVulk), Institute of Earth Sciences, University of Iceland, Reykjavik, Iceland;
2. Department of Geology, Lund University, Lund, Sweden;
3. Alfred Wegener Institute (AWI), Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany;
4. Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway