What are the "smoke rings" over Iceland?

The volcanic eruption formed a rare steam circle in the air

The steam circle lasted for about 5 minutes before disappearing.

Since the eruption of the Eyjafjallaj?kull volcano in Iceland, there seems to be no sign of stopping. Joseph Risiadi, a geologist at the University of New Hampshire in the United States, actually photographed a set of magical volcanic eruptions while inspecting the Eyjafjallaj?kull volcano. The volcanic eruption formed a rare steam circle in the sky.

As early as 2000, a volcano photographer also captured a similar scene above Mount Etna in Italy. But apart from photographic data, the cause of the formation of such steam circles remains a mystery. Ricciardi believes that the phenomenon is most likely caused by steam and gas eruptions erupting from a narrow volcanic vent, just like smoke rings exhaled from a smoker's mouth.

Risiadi said, "The steam circle lasted for about 5 minutes before disappearing. Eyjafjallaj?kull has only erupted one observable steam circle in the past month or so. This shows that this is an extremely rare phenomenon and I feel very lucky to have been able to observe it.

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