Iceland review - 2015, Blaðsíða 68

66 ICELAND REVIEW
66 ICELAND REVIEW
A VOLCANO’S WHIMS
Starting on August 31, 2014, and carry-
ing on until February 27, 2015, the erup-
tion originated in one of Iceland’s largest
volcanoes, Bárðarbunga, which lies under
Vatnajökull glacier. It was preceded by a
series of violent earthquakes. “At first, while
the earthquakes were taking place under the
glacier, we were concerned about flooding
and ash fall,” reveals Sigurður, explaining:
“We tend to look at the last scenarios
we’ve experienced: Eyjafjallajökull in 2010
and Grímsvötn in 2011.” Both sub-glacial
eruptions led to extensive ash fall—which,
in the case of Eyjafjallajökull, grounded
international air traffic for days—and a
glacial outburst flood from Eyjafjallajökull
destroyed farmland.
Given the size of Bárðarbunga and the
volume and location of the glacial rivers
potentially affected by a sub-glacial erup-
tion, the worst-case scenario was devastating.
“This was the main point of discussion with
the Civil Protection Department, which
informed inhabitants of the areas likely
affected, drawing up evacuation plans,” rec-
ollects Sigurður. “We were racing to place
samplers in glacial rivers, looking for signs,
predicting where the flooding would be
the worst. When the earthquakes extended
away from the northern edge of the glacier
we were incredibly relieved, thinking: ‘this
will be another tourist eruption.’”
In March 2010, one month before
Eyjafjallajökull burst, a minor eruption
occurred in the same volcanic system on
Fimmvörðuháls, a ridge between two gla-
ciers. The spectacular lava fountains and
falls attracted a multitude of tourists on
foot, snowmobile and helicopter. In the
case of Holuhraun, the pattern of the earth-
quakes indicated that an intrusive dike was
channeling magma away from the massive
Bárðarbunga caldera in Vatnajökull and
towards an ice-free no-man’s land in the
remote northeastern highlands, which—
were it to reach the surface—would neither
cause an explosive, ash-producing eruption,
nor glacial outburst floods.
“But then we started worrying they would
attack Askja!” Sigurður says of the next
big concern. But as the earthquakes were
approaching the infamous volcano—the
mother of some gigantic past eruptions—
they stopped in the old lava field Holuhraun
where the dike reached the surface, spewing
lava from a 1.5-km (1-mile) long fissure,
shooting fire fountains as high up as 100
meters (328 feet) in the air. Impressive as
they were, it soon became clear that this
was no ‘tourist eruption’ and the scientists
weren’t about to get a break, as Sigurður
describes: “When we realized the extent
of the gas pollution, a new race started,
putting up gas, dust and precipitation mon-
itoring stations around the country and the
Icelandic Met Office developed gas distri-
bution forecasts.”
BAD OMEN OF A BLUE HAZE
In early September a bluish haze was report-
ed in East Iceland, the result of volcanic gas
released by the eruption. “When SO2 gas
interacts with hydrogen, oxygen and sun-
light in the atmosphere, sulfuric acid par-
ticles are created and a blue haze, blámóða,
appears, after which Móðuharðindin was
named,” Sigurður says in reference to the
consequence of the 1783-84 Skaftáreldar
(Laki eruption), when toxic fumes scorched
grass and killed livestock, leading to the death
of 20 percent of the Icelandic population. The
blue haze reached the stratosphere, cooling
the climate, causing failed harvests across
Europe. “It may even have contributed to
the French Revolution,” adds Sigurður. “This
made us very concerned. The gas pollution
was extreme, peaking at 21,000 µg/m3 in
Höfn,” he recollects of the condition in the
Southeast Iceland town in late October 2014.
People were advised to stay indoors on
several occasions in different locations around
Iceland. At the eruption site, SO2 levels
reached 130,000 µg/m3, and the maximum
hourly safety limit of 350 µg/m3 was repeat-
edly exceeded across Iceland. “In some places
in Europe too, Ireland and Austria,” Sigurður
points out. Other gases released by the erup-
tion were insignificant in comparison. “The
big news was the SO2 pollution,” he stresses.
Þórólfur Guðnason, senior epidemiologist at
the Directorate of Health, stated in January
2015 that cases of people falling ill after being
exposed to volcanic gases at the eruption
site had been referred to the directorate. He
also mentioned that judging by the sale of
asthma medicine and diagnosis at healthcare
centers around the country, people had suf-
fered increased symptoms from the respira-
tory organs since the eruption started. Most
such cases were reported in East Iceland.
Concerns of acid rain and snow followed.
When SO2 dissolves in water it forms sul-
furic acid. “We started taking samples from
the precipitation and found low pH values in
many different locations around the country.
The lowest value was pH 3.2 at Borgir near
Höfn, which is extremely acid. The most
ENVIRONMENT
“The thing with dust is that it acts like base, a vaccine.
When it reacts with sulfuric acid, it neutralizes it.”