Helgi Arnar:
Mt. Tongariro vent
Helgi Arnar:
Ash-coated
Helgi Arnar:
Choosing good sampling spot
Helgi Arnar:
Volcanic ash
Helgi Arnar:
Volcanic ash from Mt. Tongariro
Helgi Arnar:
Winter is here
Helgi Arnar:
White Island eruption 2012