Earlier tonight a second harmonic pulse was seen on Grímsvötn SIL station. This time the harmonic pulse has lasted longer and is still ongoing when this is written. What is creating this harmonic pulse is unclear at this moment. But at current time Grímsvötn lake is full of water. It might well be that the water is on the move and is leaving the Grímsvötn lake. However it is not going to be clear if that is the case or not in the next few hours. I would not be surprised if it goes both ways. That is the water is on the move and that it might not be on the move at all.