Volcanoes are truly spectacular creations of nature, their eruptions being some of the greatest natural shows but their destructive power is extreme, as, throughout history, entire cities have been wiped up by volcanic eruptions.
Volcanoes are just as interesting at their quieter moments: sometimes those simmering peaks blow smoke rings intro the sky.
This phenomenon has been spotted above plenty of volcanoes around the world, but until recently, the cause of this event was uncertain. The rings are short lived and chaotic, unpredictable, therefore being a difficult test subject.
Fabio Pulvirenti, member of NASA’s Jet Propulsion Laboratory decided to do the smart thing and simulate volcano rings on a computer.
The team’s virtual volcano, which was presented at a gathering of the Asia Oceania Geosciences Society in Singapore earlier this month concluded that whatever happens within a volcano happens more or less the same in the mouth of a smoker.
Smoke rings that aren’t made out of smoke
It turns out that the smoke rings aren’t actually made out of smoke, says volcanologist Boris Behncke, who states that the rings are made out of condensed gases, mainly water vapor, escaping from the magma and evacuated from the volcano’s vent.
Strong wings greatly reduce the lifespan of a “smoke” ring, and in some cases they make the formation of smoke rings impossible.
How rings are formed
When magma rises through the conduit of the volcano, the surrounding pressure drops, allowing dissolved gasses to emerge as bubbles and if the magma’s viscosity is just right, bubbles merge into singular pockets of pressurized gas. On their way to the vent, these gas pockets can violently depressurize and explode, pushing hot vapor upward, sometimes at speeds close to the speed of sound.