Reports that the formidable Katla volcano is gearing up for an imminent eruption were premature, says a leading geophysicist. RÚV reports that a recent publication co-authored by Cambridge-educated (and Iceland-raised) volcanologist Evgenia Ilyinskaya identifies Katla as a “a globally important source of atmospheric carbon dioxide (CO2).” Although some have concluded from this discovery that Katla is signaling an imminent eruption, however, Magnús Tumi Guðmundsson, a professor in geophysics at the University of Iceland, says that the only conclusion that can be drawn is that more research is needed in order to know what the carbon emissions actually signify.
There is no way to know if Katla’s significant CO2 emissions indicate that it’s about to erupt because there’s no existing data to show whether those emission levels are normal for the volcano, Magnús wrote in a post on Facebook, and nor is it known how long they’ve been going on. “Even more unclear is whether these massive emissions are directly connected to an underground magma chamber, or what [Katla's] connection to the magma chamber in the volcano is. It’s possible that Katla works as a kind of vent or exhaust channel for gasses that are emitted from magma deep under the southern part of the volcano belt.”
It bears noting that the original article itself makes no claims that Katla is about to erupt. Rather, “Globally significant CO2 emissions from Katla, a subglacial volcano in Iceland,” which was published in the journal Geophysical Research Letters last week, states that although researchers understand volcanoes to be “a key natural source of atmospheric CO2," the current "estimates of the total global amount of CO2 that volcanoes emit are based on only a small number of active volcanoes.” As such, Evgenia and her colleagues conducted “high‐precision airborne measurements and atmospheric dispersion modelling” and were thus able to show that “Katla, a highly hazardous subglacial volcano which last erupted 100 years ago, is one of the largest volcanic sources of CO2 on Earth, releasing up to 5% of total global volcanic emissions.”
The “remarkable measurements” in the article “show that there’s still a lot we don’t know about volcanic activity and the characteristics of specific volcanoes,” wrote Magnús. “As the authors of the article point out, the conclusions call for more thorough measurements. It is, for instance, important to know whether the emissions are constant, or connected to a particular time of year. It’s possible that more measurements will shed new light on Katla’s behavior and could in this way help us further improve monitoring and risk assessment. More measurements are the only way to make a reliable assessment of the volcano’s total emissions.”
Once those measurements are in hand, says Magnús, scientists will need to reassess “what the numbers tell us about the magma under Katla and what lessons can be learned from them.”
The original article—and a “plain language summary” of its findings—is available (in English) here.