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"Violently" removed from official AMS definition of tornado

In recent years, the "official" definition of a tornado (in this context, from the AMS Glossary) has been revised. One of these was to remove the word "violently":

http://glossary.ametsoc.org/wiki/Tornado

Other revisions to the definition are discussed in this paper "A Revised Tornado Definition and Changes in Tornado Taxonomy" by Ernest M. Agee:

https://journals.ametsoc.org/doi/abs/10.1175/WAF-D-14-00058.1

I can't find much about this other than the journal article linked above, but I am assuming the reason was that many weaker tornadoes didn't meet the "violent" criteria in the previous definition.
 
No, my point is the meaning of "violent" is subjective and arbitrary. According to previous definitions, 65 mph must have been considered "violent" because it was the bottom of the EF0 wind speed range, and if a tornado was classified as a tornado, then even if it was rated EF0 it apparently, by definition, would have had to have had wind speeds of at least 65 mph. But what do you call a similar vertical vortex attached to a cumuliform cloud that produces winds less than 65 mph? Was that not violent? Who says what is "violent" and what isn't?
 
That's what I meant - originally "violent" probably meant something capable of damage, but I don't know that for sure as I've never seen the backstory of how that original definition was settled on. Contemporarily, "violent" is only used in the context of F4+ tornadoes, so it makes sense for them to remove something that's subjective at best and conflicting with another usage of the term at worst.
 
As the science advances, definitions will naturally become more specific. It's just a natural part of evolution.
 
I've always thought of "violent" as meaning EF4/EF5, and previously F4/F5. There is also the buzzword "violent", which is exemplified by the motion visible in a "digger" or a "drillbit". When I think "violent motion", I think the early-in-cycle video of the Jarrell TX 1997 tube. That was some "violent" motion.

Also, way overuse of "quotes" in this post.
 
I'd be interested in seeing a scientifically precise definition. The scale of the circulation in relation to the top wind speed seems pretty important to me for classifying low-end events. It doesn't seem like a trivial question to me.

One case in August 24, 2016 in my home town of Grand Rapids Michigan was interesting. It was a mostly unpredicted marginal event with low-CAPE and low-LCL. A tornado generated a short swath of moderate EF1 damage early in the day. Although the initial tornado was brief, the low-level mesocyclone persisted for hours and even strengthened to the point it was causing damage as it passed through the city. Tornado warnings were issued due to the TOR signature on radar, but the overall circulation remained broad and weak.

By my understanding it was simply a strong low-level mesocyclone which happened to produce wind damage at times on it's right flank. The full meso was probably 3 miles wide. The survey crew did the correct thing and classified the damage as non-tornadic (though the damage approached EF1 in spots - roughly 85 mph). Of course everyone in the public was confused as to why it wasn't classified as a tornado when there was a tornado warning. It was also frustrating for the NWS staff as it added to their "false alarm" stats.
 
You cannot be scientifically precise for a fluid object that cannot be defined. Nature doesn't care how we classify a tornado versus waterspout versus dust devil.
 
You cannot be scientifically precise for a fluid object that cannot be defined. Nature doesn't care how we classify a tornado versus waterspout versus dust devil.

While I agree with the overall attitude of the post, I totally disagree that you cannot set a definition. Yes, atmospheric phenomena occur on a continuum of spatiotemporal scales, so the difference between a vortex of width 100 m and 200 m is generally not important, for example, but that doesn't mean you can't set a width threshold for defining one of these vortices as a tornado and the other as not-a-tornado.
 
No, my point is the meaning of "violent" is subjective and arbitrary. According to previous definitions, 65 mph must have been considered "violent" because it was the bottom of the EF0 wind speed range, and if a tornado was classified as a tornado, then even if it was rated EF0 it apparently, by definition, would have had to have had wind speeds of at least 65 mph. But what do you call a similar vertical vortex attached to a cumuliform cloud that produces winds less than 65 mph? Was that not violent? Who says what is "violent" and what isn't?

Exactly, an EF0 is still a violently rotating, chaotic column of air, compared to a gentle breeze. It could be capable of putting a piece of debris into an eyeball causing massive damage. So, I guess we will wait for that to happen and someone will sue to put violent back into the definition field. People need to justify their existence. 50 years from now, he can tell his grandchild, "Yep sunny boy, I'm the guy who took the world violent out of the tornado glossary. All under your pappy's leadership."

Lol You just can't make this stuff up

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Brian - what in the world are you talking about? How many EF0 tornadoes have thrown debris into a kid's eyeball? Why is the kid in a tornado in the first place?
 
He’s just using an example. The kid doesn’t have to be in the tornado. Brian means that the tornado hurled a piece of debris for -blank- miles away.
 
EF0 tornadoes don't hurl debris anywhere near a mile... I guess my point is this - since meteorology is a science, and "violently" is not a scientifically-defined term, there's no need for it in a definition. This tweak makes perfect sense.
 
He’s just using an example. The kid doesn’t have to be in the tornado. Brian means that the tornado hurled a piece of debris for -blank- miles away.

Correct MikeD. RDale, you guys do this work on more than a Part Time basis. You're asking me like I'm stupid, "What am I taking about?" People get injured by EF0 tornados. Google it. So I found it more than comical that an authorized organization dealing with tornados would say that they are not violent winds. That's all. Or, did I miss something?


Sent from my iPhone using Stormtrack
 
Exactly, an EF0 is still a violently rotating, chaotic column of air, compared to a gentle breeze. It could be capable of putting a piece of debris into an eyeball causing massive damage. So, I guess we will wait for that to happen and someone will sue to put violent back into the definition field. People need to justify their existence. 50 years from now, he can tell his grandchild, "Yep sunny boy, I'm the guy who took the word violent out of the tornado glossary. All under your pappy's leadership."

Lol You just can't make this stuff up

Sent from my iPhone using Stormtrack




Sent from my iPhone using Stormtrack
 
Exactly, an EF0 is still a violently rotating, chaotic column of air, compared to a gentle breeze. It could be capable of putting a piece of debris into an eyeball causing massive damage. So, I guess we will wait for that to happen and someone will sue to put violent back into the definition field. People need to justify their existence. 50 years from now, he can tell his grandchild, "Yep sunny boy, I'm the guy who took the world violent out of the tornado glossary. All under your pappy's leadership."

Lol You just can't make this stuff up

I'm having a really difficult time deciphering what message you were trying to convey with this response. Can you clarify your point?
 
I'm having a really difficult time deciphering what message you were trying to convey with this response. Can you clarify your point?

Sorry Jeff, reposted incorrectly. Still trying to learn editing tool on forum with my phone

He’s just using an example. The kid doesn’t have to be in the tornado. Brian means that the tornado hurled a piece of debris for -blank- miles away.

Correct MikeD. People do get injured by EF0 tornados. Injuries by a "violent" wind. So I found it comical that the AMS would choose to remove the word violent when describing tornadoes. That's all.


Sent from my iPhone using Stormtrack


Sent from my iPhone using Stormtrack
 
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Sorry Jeff, reposted incorrectly. Still trying to learn editing tool on forum with my phone



Correct MikeD. People do get injured by EF0 tornados. Injuries by a "violent" wind. So I found it comical that the AMS would choose to remove the word violent when describing tornadoes. That's all.


Sent from my iPhone using Stormtrack


Sent from my iPhone using Stormtrack

A good edit would be to get rid of “Sent from my iPhone using Stormtrack.”
 
Correct MikeD. RDale, you guys do this work on more than a Part Time basis. You're asking me like I'm stupid, "What am I taking about?" People get injured by EF0 tornados. Google it. So I found it more than comical that an authorized organization dealing with tornados would say that they are not violent winds. That's all. Or, did I miss something?

I'd say you missed something. The fact that they removed the word "violent" from the definition is not saying that tornadoes of any intensity are not destructive, powerful, etc. While any reason I could come up with as to why they removed "violent" from the definition would be purely speculation, I'd have to agree with Jeff's explanation above of the subjective nature of the word.

Sure, people can get injured from tornadoes of any intensity. Having partaken in damage surveys of different intensity tornadoes, I can tell you that most people who are impacted directly by a tornado couldn't care less what the definition of a tornado was. They usually want to know if it was a tornado or straight-line winds, and if it was a tornado, maybe what intensity it was. I would argue the definition is used for academic, research, and operational purposes, and will most likely change again as the science advances. But that is of no concern to the general public.
 
So I found it more than comical that an authorized organization dealing with tornados would say that they are not violent winds.

Nobody said you're stupid - but you clearly didn't understand the reason it was removed. It's because "violently" is not defined in the literature, as Jeff pointed out in the very second message.
 
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