This (almost) daily post intends to follow up the activity changes of volcanoes all over the world.
This post is written by geologist Richard Wilson who specializes in Volcano seismicity and Armand Vervaeck.
Special Iceland Glacial Flood update 25/08 – 16:11 UTC – Vatnajökull
Earlier today a ice mass has melted due to thermal activity below the glacier of the Vatnajökull.
The origin of the melting was the Skaftárketill cauldron, an hydro-thermal area inside Hamarinn volcano
The glacial flash flood is currently going down the Skafta river towards the sea. Civil Defence Iceland reports that the flash food (bigger flow of water probably containing also ice and some toxic gases) is not really dangerous if people are staying away from the river bed.
The more important flow will normally arrive in sparsely populated areas later today, during the night or tomorrow morning.
An airplane overflying the glacier has confirmed the Jökulhlaup (Icelandic for Glacial Flood).
Jökulhlaups are a common feature in Iceland with so many volcanoes covered by ice. A Jökulhlaup does not necessarily mean an upcoming eruption but can be a step towards one. Not in this case though. At least it means that the volcano seismicity or temperature has been more active than before.
The Skafta river where the glacial flood is expected to flow, takes the melting water of nearly 1400 sq. miles. The glacial flash floods are known to have a strong sulfur smell. Since the giant eruption of the Laki volcano which filled up the broad river valley with lava, there is no longer a well defined river bed.
Road Nr. 1 passes the river but has not been closed. During the last big Jökulhlaup a few months ago, a bridge was swept away by the ice and had to be reconstructed.
Update 22:30 UTC :
The video below shows an overflight during the morning hours. The steaming activity can well be seen
Earthquake activity Vatnajökull glacier – Image courtesy Iceland Met Office
Read the rest of the article quite some observations listed for volcanic/seismic activity