When Eyjafjallajökull erupted in 2010 it caused widescale
travel chaos as most European air space was closed for
several weeks due to ash dispersal. Following this there is
now worry that Katla will erupt, as throughout historical
records each eruption at Eyjafjallajökull has been followed
by an eruption at Katla within a few years. Katla eruptions
tend to be at least 10 times more powerful than the
Eyjafjallajökull 2010 eruption. Katla usually erupts twice per
century but has not erupted since 1918, further fuelling fear
that Katla will erupt soon.
However, little is known about what influenced the
behaviour of the 1918 Katla eruption. It produced a 14 km
high plume which blanketed half of Iceland in ash. What was
controlling the ash production; volatiles or magma-water
interaction? Where was the magma stored prior to eruption?
How quickly did it rise to the surface? The eruption also
produced a massive flood. The peak discharge rate, at
300,000 m3 s-1
, was greater than that of the Amazon, and was
reached within just a few hours. How did the eruption
manage to generate so much meltwater, so quickly?
These are some of the questions, we hope to answer. To
help us, we will use, amongst other resources, the lessons
learnt from my PhD. This investigated the role of volatiles in
determining the explosivity of subglacial rhyolitic volcanism
at Torfajökull.
By answering these questions, we can potentially shed
light on how the next (imminent?) eruption of Katla will
behave, how much warning we will have and when the most
hazardous periods will be.