Geology

The colour code for Katla volcano raised to yellow — a new and powerful earthquake swarm hit at noon

By Staff

Katla volcano The home to the large caldera is in Mýrdalsjökull glacier. Eyjafjallajökull glacier is to the left (south). Image by NASA/Earth Observatory

Another quite powerful earthquake swarm hit Katla volcano at 12.03 (12.03 pm) today when several quakes larger than magnitude 3 struck at the volcano. The Iceland Met Office (IMO) has raised the aviation colour code from green to yellow in accordance with recommended International Civil Aviation Organisation (ICAO) procedures. This alert is issued when a volcano is exhibiting signs of elevated unrest above known background level.

The police commissioner of South Iceland has sent out units to visit Þakgil canyon and other popular travel destinations close to Mýrdalsjökull glacier, the home of the sub-glacial volcano, to warn people who might be in the area.

Read more: Around 200 earthquakes have hit the large sub-glacial volcano Katla in the last 24 hours

Scientists are concerned as the volcano’s behavior is quite unusual. The earthquakes’ points of origin are shallow and there are no signs of volcanic tremors, but the experts say the quakes might nevertheless be a sign of an impending eruption.

The experts will meet with Iceland's Civil Protection at 14 (2 pm) to assess the situation.

The colour codes

Colour codes are intended to inform the aviation sector about a volcano's status. Notifications are issued for both increasing and decreasing volcanic activity, and are accompanied by text with details (as known) about the nature of the unrest or eruption, especially in regard to ash-plume information and likely outcomes.