This is a short update on Grímsfjall volcano/ Grímsvötn eruption. This is short update because a lot of details in this eruption are still unclear at this moment.
Process of the eruption: The eruption in Grímsvötn is still growing strong. Icelandic Met Office SIL sensors show a uneven process in the eruption. But they also show that the eruption has dropped a little bit in power since it originally started in yesterday. That is normal for a eruption in Grímsfjall volcano. It starts strong and then slowly drops in power over time. But what is unusual for this eruption is the uneven process that is taking place (seen with SIL data) in the eruption. What that means is unclear. It is more unclear what it means to the eruption. While it is unclear at the moment. It appears that the eruption is taking place a little south of the eruption in the year 2004. But that is unconfirmed, as ash cloud to the ground blocks the view the eruption site.
Ash cloud: The ash plume is reported to have reached 20 km high yesterday. From as I can gather that has not changed. This ash plume appears be made from two to three ash cloud columns. With the strongest one getting the highest. A lot of lightning is taking place in the ash cloud. Due to the ash cloud, all flight from and to Iceland has been cancelled until further notice (don’t ask question about that here, ask your airliner for information about this closure). The ash did start to fall in populated areas few hours after the eruption did start in Grímsvötn. The ash is described as fine, but more crude (bigger particles) then the ash from Eyjafjallajökull volcano eruption in the year 2010. The ash cloud is moving west in higher layers of the atmosphere over Iceland. While it moving south in the lower layers of the atmosphere as the wind is from north in Iceland at the moment.
Earthquakes: After the magma has found it’s way to the surface. All earthquake activity did stop in Grímsfjall volcano. This is normal. But what is unusual is that there have been few earthquake swarm after that in Grímsfjall volcano. I do not know what it means or why this is happening. But this is interesting development.
Other: The earliest estimation on the size of the Grímsfjall volcano eruption 2011 is that this looks like it is a bigger eruption then in Eyjafjallajökull volcano eruption in the year 2010. But that is closer to speculation based on visual observation of the eruption. But it is clear that this eruption is bigger then the year 2004 eruption in Grímsfjall volcano.
A new video has been relased of the eruption. It is from yesterday when the eruption was starting.
Update 1: They now say that this is the largest eruption in Grímsvötn / Grímsfjall volcano in the last 100 years. Rúv news about this, Stærsta gos í Grímsvötnum í 100 ár (Icelandic).
Please note that information here might get outdated really fast and with no warning at all!
Update at 09:24 UTC.