Water devil - or how would you describe this?

[ChristofferB]

I found this cool video clip from the Faroe Islands in a Scandinavian storm Facebook-group.

https://www.facebook.com/video.php?v=2333985086814358

The one who posted it called it a tornado but I think it is just a matter of bad translation. As we so rarely get tornadoes here there is little use of defining a vortex other than a tornado (or "tromb" in Swedish), small tornado or water tornado - which also includes dust devils. But, given what we can see in this video I find it very unlikely that this would be a proper tornado, right? Some claim it to be.

My guess (and I have very little knowledge about aerodynamics) here is that wind is coming in from the sea, is forced up by the rock formation, the curvature in the rock is causing the wind to rotate and is thus causing a vortex. The high amount of water vapor (and moisture) in the air is making this vortex visible.

As there is no apparent (storm) cloud above and it even seems to be overcast one cannot at least say for a fact that it is a tornado, right? One would need the whole view to "prove" this is a tornado, right?

The same goes for a water spout. A water spout is caused by an updraft (although not mesocyclonic) in a storm cloud and as this cannot be seen (or is not even likely) it wouldn't be a water spout either, right?

I am not sure if "water devil" is a word but I wouldn't even believe this to be a "water devil" (i.e. a dust devil on water) either. I guess if the definition of a dust devil is a visible column of air then this could be a "water devil". Then again, dust devils are created under completely different (hot and dry) circumstances.

Am I wrong? If not, what could this be defined as in that case? A cliffnado?

 

[Alex Elmore]

In these sorts of discussions, the AMS definition of a tornado is usually cited: "A rotating column of air, in contact with the surface, pendant from a cumuliform cloud, and often visible as a funnel cloud and/or circulating debris/dust at the ground". Given that this vortex is not anywhere close to the cloud base, I'd say it's not a tornado.

Your explanation of the interaction between the wind and rock formation is probably what is going on here. The cliff appears to be concave in that area, and that may be causing a circulation to develop due to the direction of the wind and how it's striking the cliff. The air moving up over the cliff is most likely the source of lift/stretching needed to tighten the circulation into a visible vortex. This would also explain why the vortex remains stationary, as the the conditions needed to maintain it are only present right there. Seeing as the camera was trained on that specific area before it even formed leads me to believe that the person filming had seen this happen at least once shortly before the video took place, which again supports the wind/cliff formation theory.

As for what to call it other than simply a vortex, it's not a tornado or water spout, so whatever other than those will probably work

 

[ChristofferB]

Alex: Great input there. I didn't consider the wind blowing over the cliff as a source of lift but that seems very likely. I read afterwards that the winds were extremely fierce that day on Faroe Islands.

I also made the same observation that this was likely not the first vortex of the day, as he was filming it from before it even started. He was probably out to watch the storm hitting the cliffs and noticed vortices building up by the cliff side.

Also, check out this photo taken from the other side. Imagine walking the cliffside and see this! http://local.fo/wp-content/uploads/2020/01/81448748_3223200171026681_8759195589528256512_n.jpg

 

[Jeff Duda]

Not all "vortices" have to have fancy names.

This is just a vortex that had enough pressure drop to condense. And that's it.

Excessively cool video, though.

 

[Dan Robinson]

This seems similar to the vortices that can form in the intakes of jet engines - just a very fast & converging airflow that can easily stretch and maintain a vortex. I've never seen one like that though, very cool. Probably requires wind hitting that cliff at just the right angle and speed.

 

[Paul Knightley]

This video came into my FB feeds too - and the explanations above fit my ideas too...the wind is accelerating up and over the cliff, and a vortex happened to get into the part where some intense lifting was going on, which stretched and intensified it. The Bernoulli 'effect' of the flow running up and over the cliff top/along with higher wind velocities per se at the cliff level that at sea level, would have induced a pressure drop/acceleration of lower-level parcels.

 

[Jeff Wright]

If it were strong enough--gustnado.

The C-17s have the best vortices

How does this vortex form inside a jet engine?

I have seen this in a picture once online and thought it was very strange and wondered about the formation of this vortex and how could it happen. Source Not everyday do you see this happening. S...

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