Volcanoes, the Internet, and the Public's Role in
Science, How the 2010 Eruption of Eyjafjallajökull was the First 21st Century
Eruption
Erik Klemetti (Department
of Geosciences, Denison University, Granville, Ohio, USA)
Ohio State University at Newark Geology Club
presentation
16 November 2010
Will
be talking about Eyjafjallajökull Volcano. Seemingly unpronounceable, but
“Eye-jah-fyah-la-yo-kul”, or “eye-jah” for short. Some consider the “ll”
to be pronounced as “tl” in Icelandic, however.
In
the pre-internet age, information about geologic events was filtered through
the media only before it got into the public’s hands.
Now,
information dissemination routes are very complex - the media is almost
excluded now.
The
public is now closer to events - information can be determined more quickly and
more directly.
But,
there’s much more info. to sort through.
In
2008, Erik Klemetti started a new volcanoes web log (“blog”) called Eruptions.
Pre-2008
volcano web logs weren’t written by geologists. Klemetti decided there
was a place for a geologist-written volcano web log. Eruptions
gets ~150,000 hits a month. During the Iceland volcanic eruption, Eruptions
got ~700,000 hits a month.
Klemetti
uses the web log to dispel idiotic ideas in the media, and uses it to get
people talking about volcanoes.
https://www.galaxyzoo.org/- an astronomy
website that uses “crowdsourcing” to get science done.
Earlier
this year (2010), an impact was observed on Jupiter - it was recorded by an
amateur - no professional astronomers saw it.
Crowdsourcing
can also be used to get information about volcanic activity.
Iceland
- it’s a weird place. It’s in the middle of the North Atlantic
Ocean. Locals eat rotting shark. The Mid-Atlantic Ridge runs right
through Iceland. Two tectonic plates are spreading apart through the
island. There’s also a mantle plume (hotspot) at Iceland.
This results in subsurface melting and magma generation - lots of volcanoes
occur on Iceland. Icelandic volcanoes include Hekla, Krafla, Katia, Laki,
Grimsvötn, etc.
Laki’s
1783 eruption is one of the biggest in history. More basaltic lava was
erupted from Laki than has been erupted anywhere in quite some time.
Erupted volcanic gases from Laki resulted in noticeable climate change for a
while.
Eyjafjallajökull
is named for the icecap atop the volcano. Glacial ice fills the
caldera. Under the glacial ice are vents from the old volcano.
1821-1823
was the last Eyjafjallajökull eruption - it was explosive (VEI 2). There
are tens to hundreds of VEI 2 explosive eruptions every year, globally.
1612
- Eyjafjallajökull had a VEI 2 explosive eruption.
920
A.D. - Eyjafjallajökull had a VEI 3 explosive eruption on its northwestern
flank.
Eyjafjallajökull
is not really regarded as very active, compared with other Icelandic volcanoes
such as Hekla. Eyjafjallajökull was not high up on the list of volcanoes
that people thought would probably erupt.
So,
it was surprising to many that Eyjafjallajökull erupted - it caught people
off-guard.
March
4, 2010 - Eyjafjallajökull inflation was noted, plus seismicity at 10 km below
the surface.
The
Iceland Meteorological Office (IMO) said that the activity was not going
to lead to an eruption.
Many,
many volcanoes inflate and deflate and have earthquakes all the time with no
eruption - this is why the IMO said that.
Amateur
geophone observations - earthquakes were getting more shallow through time.
An
amateur did predict an Eyjafjallajökull eruption - posted 5 March 2010 on the Eruptions
web log.
20
March 2010 - 16 days after the IMO said nothing will happen, an
Eyjafjallajökull eruption began. People saw a glow from the glacier and
noted ash falling near the glacier. This was the start of a fissure
eruption east of Eyjafjallajökull. Amateurs reported on web logs well
before the media got involved.
Earthquakes
had happened under Eyjafjallajökull, but the eruption happened well to
the east of the volcano, between it and the next volcano eastward.
So
the earliest phase of the 2010 Eyjafjallajökull eruption was along the
Fimmvördulháls Fissure. Lava was erupting into snowpack - got some
phreatomagmatic eruptions. The lava flows received many close visitors -
close examination was relatively safe.
31
March 2010 - a second fissure appeared 11 days after the first fissure appeared
- it was perpendicular to the first. The new fissure was visible on
webcams - the new eruption could’ve been observed from the initial moment on
live video.
12
April 2010 - the IMO said the eruption was winding down.
13
April 2010 - the Icelandic media reported that the Eyjafjallajökull was over.
Late
13 April 2010 - lots of new shallow earthquakes were noted under the volcano,
not under the fissure. Water discharge levels in a river draining from
the volcano were observed to be quickly rising at night - that shouldn’t
happen.
Late
13 April 2010 - a new eruption started under the icecap, it’s being realized by
people.
So,
in 24 hours, there was a complete turn-around in people’s perceptions about
Eyjafjallajökull activity.
Eyjafjallajökull
goes explosive.
This
phase of the eruption occurred at the caldera center, at the main
glacier/icecap.
An
ash plume went 8 to 10 to 15 km high in the atmosphere.
Why
explosive volcanism now? Two factors behind this:
1)
higher silica content to the magma/lava - now 47-58% SiO2 - more
viscous, so gas pressures increase beyond the strength of the rock, resulting
in explosive shattering of the rock - ash eruption.
2)
more lava interaction with water - the lava erupted under the glacier, instead
of under snow, resulting in the generation of much water, which mixes with
lava, resulting in steam explosions that shatter rock - ash eruption.
Eyjafjallajökull
changed from having a quiet eruption to an explosive eruption.
Eyjafjallajökull
ash - Klemetti got boxes of it sent to Denison. Early ash was
dark-colored - less silicic.
Eyjafjallajökull
ash was a mix of fragmented volcanic glass and volcanic minerals (feldspar,
pyroxene, magnetite, oxides, etc.)
Jet
engines and ash just don’t mix.
If
ash gets into an airplane engine, the ash melts and surfaces get coated with
glass - bad for the engine.
Even
dilute ash (ash you can’t even see) can cause stalled jet engines.
Planes
need to fly below volcanic ash clouds in order to restart engines.
This is opposite to the normal tendency of pilots to fly over clouds.
“The
Ash that Ate Europe”
Klemetti
thinks it was correct to shut down flights in Europe - why take the
chances? There have been no ash-airplane disasters yet, but. . .
Airlines
claimed a $200 million dollar loss a day during the shutdown.
It’s
remarkable that a small eruption shut down European flights for a week.
Europe
and North Africa were affected for quite some time. That was early in the
2010 Eyjafjallajökull eruption history.
Summer
2010 - Eyjafjallajökull hasn’t done anything.
Now
- Eyjafjallajökull is quiet.
Internet
response to the eruption - Erik Klemetti’s web log has a hit peak when the
fissure eruption started, followed by a huge hit peak during the airspace closure.
From
15 to 24 March 2010, the Eruptions web log had 1.22 million hits.
The
media’s Katla-mongering: Katla has relatively frequent eruptions, so it’s a
coincidence that Katla erupts close in time to the infrequent Eyjafjallajökull
eruptions. The media likes dramatic stories, so they will force
connections that don’t exist. Ex: Haiti and Chile earthquakes -
the Earth is becoming unstable! Ex: the Merapi eruption and the
coincident large earthquake in Indonesia.
Volcanologists don’t make predictions -
they provide probabilities.