the recent eruptions before that occurred in 2004 and 1998. The eruption in 2011 was significantly larger than other recent eruptions at Grímsvötn volcano. To find an eruption of similar magnitude one needs to
go back to 1873. The 2011 eruption started in the evening of 21st of May and lasted for almost seven days. The ash cloud reached maximum 20 km a.s.l. and was seen in the beginning of the eruption
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