Holuhraun gas model

The volcanic eruption in Holuhraun continues

The following are the latest facts about the volcanic eruption in Holuhraun, put together from the Scientific Advisory Board of the Icelandic Civil Protection:

The volcanic eruption in Holuhraun continues. A visible reduction has been on the eruption in the last two weeks. Seismic activity in Bardarbunga continues to be strong. The strongest earthquake since the last meeting of the Advisory Board on Tuesday was measured M4.9 tonight at 03:48. Two other earthquakes stronger than M4,0 were detected since Tuesday, one was M4,5 and the other M4,0. About 10 earthquakes between magnitudes M3.0-3.9 were detected over the period. In total around 110 earthquakes were detected around the caldera since last Tuesday. No earthquake over M5,0 has been detected in Bardarbunga since 8. January. Around 20 earthquakes were detected in the dyke during the same period. The strongest one was M1.8. GPS measurements near northern Vatnajokull glacier show continuing slow deflation towards Bardarbunga.

The highest levels of sulphuric dioxide since Tuesday, 3rd of February, 800 µg/m³ SO2 was measured in Vopnafjordur on Tuesday. A new risk analysis for the area around the eruption site is being conducted. The new risk map for the area will be issued next week.

A team of technicians from The Icelandic Met Office, Institute of Earth Sciences UI, and The Department of Civil Protection have been working on maintenance on measuring equipment’s on Vatnajokull glacier and in the surrounding area. The GPS station in the Bardarbunga caldera is back on-line and will be visible on the IMO web site as before.

Air quality:

  • Today (Friday) and tomorrow (Saturday) gas pollution will affect the area northeast and east of the eruption in Holuhraun.
  • The Icelandic Met Office provides two-day forecasts on gas dispersion from the eruptive site in Holuhraun. Most reliable are the forecast maps approved my meteorologist on duty, see Gas forecast. And although still being developed further, an automatic forecast, see Gas model, is also available (trial run, see disclaimer).
  • Measurements of air quality can be found on the webpage www.airquality.is  Data from handheld gas monitors, spread around the country, can also be found on that page

Instructions from the Crisis Coordination Centre:

  • People who feel discomfort are advised to stay indoors, close their windows, turn up the heat and turn off air conditioning. Use periods of good air quality to ventilate the house. People experiencing adverse effects should be in immediate contact with their healthcare centre. Measurements of air quality can be found on the webpage www.airquality.is The Meteorological Office issues forecast on its web-page and warnings if conditions change to the worse.
  • Instructions from The Environment Agency of Iceland and Chief Epidemiologist can be found on their web-sites.
  • Check the Icelandic Met Office forecasts for sulphuric gas dispersion on the web as described above.
  • Handheld meters have been distributed around the country for SO2 measurements three times a day.
  • Information and any questions on air pollution can be sent to The Environment Agency through the email gos@ust.is. The Environment Agency is especially looking for information from people who have been in contact with high concentrations of gas; where they were, at what time it happened, how the gas cloud looked (colour and thickness of the cloud) and how they were affected by it.

Three scenarios are considered most likely:

The volcanic eruption has now been going on for five months, the lava flow is still great in Holuhraun and the rate of the subsidence of the Bardarbunga caldera is still significant.

  • The eruption in Holuhraun continues until the subsidence of the Bardarbunga caldera stops. The eruption can still go on for many months.
  • The volcanic fissure may lengthen southwards under Dyngjujokull, resulting in a jokulhlaup and an ash-producing eruption. It is also possible that eruptive fissures could develop in another location under the glacier. If such an eruption would be prolonged it could eventually produce a lava flow.
  • Volcanic eruption in the Bardarbunga caldera. Such an eruption would melt large quantities of ice, leading to a major jokulhlaup, accompanied by ash fall.

Other scenarios cannot be excluded.

The National Commissioner of the Icelandic Police, Department of Civil Protection and Emergency Management Almannavarnir  www.avd.is/en Twitter: @almannavarnir