It has just been reported that (today 14. April 2023) that there is now a high levels of Hydrogen sulfide (H2S) close to Múlakvísl glacier river that comes from Mýrdalsjökull glacier, that is on top of Katla volcano. Tourists have been asked to be careful in the area. Currently the conductivity in Múlakvísl is not high, but according to Icelandic Met Office that is expected to change in next few hours.
Earthquake activity in Katla volcano at the moment is at normal background levels, that might change without warning if there is anything more happening with this sudden increase in gas levels. The gas levels changed early morning on 13. April 2023 according to Icelandic Met Office website.
Isn’t it a bit weird that no other event has accompanied the rise of the gas? The water level in Múlakvísl has remained normal and steady, and it’s been very calm with EQ activity for well over a week. Could it have been just a small cauldron that has emptied? Conductivity looks stable still.
I am not good in knowing what is happening in the glacier. But that is a possibility that a cauldron did emptied without any of the earthquake activity or any other signs that sometimes follow. I don’t know how often this happens early in the spring in Iceland.