The following information on the volcanic eruption in Holuhraun was extracted from the Department of Civil Protection and Emergency Management’s National Crisis Coordination Center’s status report, sent to the media this afternoon.
The intensity of the ongoing eruption in Holuhraun is not declining. Lava is flowing toward east-northeast and it has been elongated considerably since yesterday. Since this morning, a preliminary estimate of lava field extension is about 11 square km (4.3 square miles).
Seismic activity is still detected in the northern part of the dike intrusion, along the eruption site and extending south below Dyngjujökull. Event rates are lower than in recent days, 180 earthquakes have been detected since midnight until noon.
The low frequency tremor seen yesterday disappeared last night but started again this morning, however minor compared to yesterday. The source of the tremor is not certain however possible explanation could be magma-water interaction although this interpretation has currently not been confirmed by other observations.
There are no signs of a sub-glacial eruption under Dyngjujökull. No obvious changes such as increased water flow or cauldrons on the glacier surface were observed from scientists on board TF-SIF yesterday. Water meters in Jökulsá á Fjöllum do not show any unusual changes in discharge and electric conductivity.
The GPS time series indicate slower rate of deformation in the last 24 hours. The current de formation pattern north of Vatnajökull still suggests volume increase in the dike. No significant signs of deformation are observed around Bárðarbunga.
There have been no observations of ash fall away from the eruption site. Ash production is negligible. Based on radar images the eruption cloud from today (composed of steam and volcanic gases) has not drifted far away and is mostly concentrated around the eruption site.
Stations measuring SO2 further away from the eruption site are showing concentration below health and safety thresholds. Since this morning, the cloud reaches 6 km of altitude. The volcanic cloud will drift towards south in the coming hours due to wind rotation.
Sulphur dioxide emission continues. Low wind speed condition is present in the area at the moment. People could be exposed to highly dangerous gas levels close to the eruption. It is essential that those working near the eruption site are equipped with gas sensors and gas masks.
In light of GPS, radar and seismic results, it is possible that the ongoing eruption could progress southward under Dyngjujökull. This would lead to immediate flooding hazards on the floodplain in front of Dyngjujökull. Consequently, risk assessments for scientists working in the area are periodically assessed.
Yesterday, the district commissioner in Húsavík decided to further restrict access to the eruption site northwest of Vatnajökull glacier, due to increased tremor at the eruption site in Holuhraun. The restrictions were lifted this morning.
The road to Dettifoss on the west side of Jökulsá á Fjöllum (862) has been opened for traffic from the Ring Road to the Dettifoss waterfall.
Other roads on the west side are still closed, including hiking trails. The decision is based on the Civil Protection Department’s risk reduction measures, increased surveillance of the Vatnajökull National Park rangers, increased scientific monitoring as well as additional law enforcement. The decision does not in any way indicate less flood risk, only increased mitigation and surveillance.
All roads leading to the volcanic site are closed based on the risk of a flood if an eruption will start under the glacier. Information on closures can be found on the Icelandic Road and Coastal Administration web page.
The aviation color code for Bárðarbunga remains at ‘orange’ and the code for Askja at ‘yellow.’