The 2011 eruption of a 20-km-high volcanic plume from Grímsvötn Volcano, Iceland, led to the closure of northern European airspace. Geodetic measurements from the volcano reveal a correlation between plume height, surface deformation and magma-chamber pressure, implying that volcanic plume behaviour can be predicted before eruption onset. The image shows the Grímsvötn volcanic plume on 21 May 2011, at an altitude of about 10,000 feet and within an hour of the start of the eruption. The aircraft is a 4-seat Piper Cherokee Warrior.
Article p214; News & Views p168
IMAGE: OLAFUR SIGURJONSSON
COVER DESIGN: DAVID SHAND