I have two things to say about this super high-res footage of a fire tornado spinning beautifully in a bucket: wow, and wowowow. Even getting up close to a live, flickering flame IRL won't give you the perspective that this video by the Slo Mo Guys provides, as the twisting motion of the towering tornado looks like billowing ink blots in the slowed down footage. It almost doesn't look real, but this is nature at its absolute best. As Gavin notes in awe, "That's class."
Welcome to the moment when two of the most fascinating natural phenomena - tornadoes and wildfire - are combined in all their glory... and confined within a humble metal bucket. Fire tornadoes do actually occur in nature, but they're quite rare, and can come in many different forms depending on the environmental conditions that trigger them.
As Elizabeth New reports for Australian Geographic, in order for a vortex to form in a wildfire, a 'shear' must be present. Shears are created when one flow of wind or fire is perpendicular to another flow, which forms a particular type of turbulence that gives rise to a whirling vortex.
"If there is already a shear present, whirls will form regardless of the size of the fire," CSIRO fire researcher, Andrew Sullivan, told her. "If there isn't a shear present, then larger fires will tend to induce them. Depending on the intensity of the fire, you can get updrafts. This forms a shear layer moving in two directions that induces a vortex."
Instead of embarking on the very dangerous - and stupid - quest to chase natural fire tornadoes, the Slo Mo Guys recreated the phenomenon using a circle of 12 box fans arranged on some dry, clear ground, and just over a centimetre of kerosene in a bucket. (Needless to say, don't try to build your own firenado at home, okay?)
The boys manage to build up a 3-metre fire tornado, and when you see the results of their filming, you'll see why they bothered. It's just incredible. "I'm always waffling on about how liquids and flame looks good, but spinning flame - even better. I think from now on, all flame should be spinning," says Gavin.
And guess what? Thanks to this video, those of you who forked out for 4K TVs way too early have finally, finally, got something to watch. Enjoy.
If you want to see a real, very deadly, firenado, check out this footage shot in the Australian Northern Territory: