“Since the last eruption of the Hekla volcano in southern Iceland in 2000, the ground has been steadily rising here,” Páll Einarsson, geophysicist and professor emeritus told Morgunblaðið. He added that already in 2006 inflation was as high as before the eruption in 2000. It can be said that since then the volcano is ready to erupt.
However, there are no visible signs of this. “Hekla shows no signs of an impending eruption until just before it occurs” Says Páll. “That’s what makes her so dangerous.”
The pressure causing inflation seems to originate at a depth of 15–20 km. “This is where magma probably accumulates” Says Páll. “And that’s where it seems to come from in the recent eruptions. This is suggested by soil deformation measurements. The area that is inflated by Hekla is about 30 km in diameter. “
Hekla once erupted on average twice every hundred years. A major eruption occurred in 1947, followed by an unexpected eruption in 1970. Subsequent outbreaks occurred in 1980, 1991, and 2000, the latter being fairly small. Scientists used to think that the longer the pause between eruptions, the greater the force of the blast, but Páll says this rule is not without exceptions.
Before Hekla’s last eruption, signs of an eruption appeared 79 minutes before the event. In 1980, the warning became noticeable no more than 23 minutes before the incident. Those most at risk are hiking in the mountains as escape can be difficult. Páll says that only those who urgently need to collect data should go there. In addition to caring for tourists, Páll also worries about the passengers of the planes that fly over Hekla.
Responding to these concerns, Árni Guðbrandsson, a specialist at Isavia ANS, which is responsible for air navigation over Iceland, tells Morgunblaðið that Isavia ANS conducted a risk assessment in 2016 in collaboration with the natural hazards department of the Icelandic Meteorological Institute. They concluded that there was no need for changes to the routing of flights over Iceland due to the risk of an eruption.
Source: Yle