Rating Tornado Intensity Based on Moblie Radar

[rdale]

I just don't want skewed data that may affect future actions and policies.

What does that mean? What actions or policies are based on blind EF scale numbers?

 

[STexan]

What does that mean? What actions or policies are based on blind EF scale numbers?

An EF5 hits Moore, and within an hour there were calls from citizens and politicians for mandatory storm cellars for all schools and businesses, as well as politicians trying to blame the Moore tornado on man made climate change ... all this within an hour or two of an "extraordinary" weather event. Make EF5's go from a rare occurrence to an almost routine and expected occurrence in the course of a season, and I guarantee you will see a lot of knee-jerk reactions from all sorts of people, groups, governments, and organizations. That's what I mean.

 

[STexan]

I was trying not to say that because I know how some here get all bent out of shape if politics and government enters any discussion here ... which is strange given that government and politics drives NOAA, NWS, SPC, NHC, etc. and that there are many int'l treaties that affects billions of people across the globe including us, that are centered and "climate change" and so many try and connect extreme weather with "climate change".

 

[Rob H]

I think it was Harold Brooks on Weatherbrains that put it rather well: the issue he sees is that people want the EF scale to turn into a single entity that completely defines the strength of a tornado, when it reality it can't achieve that. His thought was to leave the EF scale as is for now, but to continue having the discussion, and allow for measured winds to be captured at the same time. The EF scale still rates damage and no policies have to change, however we now have additional detailed information to assist with scientific research and forging future public policy.

 

[Jake Orosi]

Trying to figure out what the objective downside to mandatory storm shelters for all schools would be.

 

[rdale]

Trying to figure out what the objective downside to mandatory storm shelters for all schools would be.

The immense cost. Especially for older buildings where it is incredibly immense. More kids have died from playground injuries in the last 5 years during school than have died from tornadoes in the last 50.

 

[Jake Orosi]

The immense cost. Especially for older buildings where it is incredibly immense. More kids have died from playground injuries in the last 5 years during school than have died from tornadoes in the last 50.

Maybe; but when playground deaths occur usually equipment is fixed/removed/repaired/redesigned in response isn't it? At immense cost.

Meh, but I suppose you're right. Communities these days are reluctant enough to buy their schools up-to-date textbooks and fix roofs that are actively leaking all over their kids; so I guess a tornado shelter is something of a wild fantasy.

 

[Shawn Schuman]

Yeah, it is. I would much prefer better schools than shelters at schools. Tragedies like in Moore influence our thinking and it's tempting to get worked up about doing anything and everything we can to prevent it, especially in schools, but the fact is it's extremely rare. For example, quick, when was the last time more than ten children were killed at a school? April, 1967 in Belvidere, Ill. Now even one child's death is too many, of course, but it illustrates how rare it is. Now think of how many children die in stores and homes and almost every other place but a school. We aren't likely to call for mandatory shelters in all those places.

There have been a total of 291 confirmed deaths in schools.. total. Take out the 69 deaths during the Tri-State Tornado and you've got 222. That's for more than 150 years, and the majority were many decades ago.

 

[Chris Nuttall]

Every one is caught up in the rating. The only people that care about the ratings are meteorologists, climatologists, engineers, insurers, and weather weenies (not using this as a derogatory term), but mainly for research or record keeping purposes. Sure, I guess it can serve as guide for engineers to build better structures. In the grand scheme of things, if damage is done and people are hurt or killed, the human impact is the same, which is a point that is being lost in this debate.

 

[Shane Adams]

There's been a mobile radar running around out there in some form for 17 years now. Either we (a) need to start using all that tax-funded data for something tangible regarding tornado ratings or (b) stop sending them out. I understand earth curvature and the lowest 100 yards and all that crap. But I'm as confident a wind measurement taken at 600 feet off the ground can be extrapolated by all those brilliant scientists down to a fairly accurate surface wind speed as I am in all the research that went into determining exactly what type of winds could cause the damage in each of the 24,967 DIs there are now.

This is why science loses me; right when it gets on the cusp of something truly amazing, a debate rises up because some people want to split hairs over crap that there's no way to know if it's truly accurate. If extrapolation of 500m winds down to the surface isn't good enough for you, then how can you sleep at night knowing there's 40,000 DIs and that the research for each one is based on ESTIMATION of wind speed potential?

But at the end of the day, who gives a sh*t what the rating is?

 

[Jake Orosi]

Every one is caught up in the rating. The only people that care about the ratings are meteorologists, climatologists, engineers, insurers, and weather weenies (not using this as a derogatory term), but mainly for research or record keeping purposes. Sure, I guess it can serve as guide for engineers to build better structures. In the grand scheme of things, if damage is done and people are hurt or killed, the human impact is the same, which is a point that is being lost in this debate.

If researching and record-keeping is superfluous and beside the point, why bother to scientifically study storms at all? Warn every storm; if someone dies it's a tragedy and if nobody does who cares?

 

[Chris Nuttall]

If researching and record-keeping is superfluous and beside the point, why bother to scientifically study storms at all? Warn every storm; if someone dies it's a tragedy and if nobody does who cares?

So, you're telling me that rating the El Reno tornado EF-5 versus EF-3 is going to directly lead to an improvement in the warning system? I did not say that researching and record-keeping is pointless. It is important. However, if 20 people are killed by a tornado, does it matter if that tornado is rated EF-3 or EF-4? I appreciate the passion on both sides of the argument, but my point is that it seems like a small thing to argue over given the death and destruction. Don't get me wrong, as a meteorologist, the final rating is important to me, but I don't have a strong feeling either way about the use of radar in determining a rating, so I'm not going to get bent out of shape. It's definitely an interesting debate, and exciting, too, because it's demonstrating a great advancement and application in technology. In the area I work, the odds of me ever having a mobile radar measurement are fairly low. Yes, I have Doppler envy. There I said it.

I guess it all depends on your audience. Maybe I'm looking at things too broadly. I tend to always look at things on the large scale. How does the vast majority of my customers, city/state/county officials, media, and the general public view this? Five years from now, the majority of the general public probably won't remember what the El Reno tornado was rated or that mobile Doppler radar measurements were used to upgrade the rating.

 

[Chris Nuttall]

I'm not sure if this has been mentioned, but just in case it hasn't, I meant to point out that the EF-scale proposal document that was released by the Wind Science and Engineering Center from Texas Tech Univ. does say on page 14:

"The technology of portable Doppler radar should also be a part of the EF Scale process, either as a direct measurement, when available, or as a means of validating the wind speeds estimated by the experts."

http://www.spc.noaa.gov/faq/tornado/ef-ttu.pdf

 

[rdale]

That's not the official NWS EF-scale document though

 

[Rob H]

This is why science loses me; right when it gets on the cusp of something truly amazing, a debate rises up because some people want to split hairs over crap that there's no way to know if it's truly accurate.

I don't know if I'd call getting more accurate EF ratings truly amazing. Who cares if it was EF-3 or EF-5? If you want to study the effects of an EF-5 on structures, you can't look at the El Reno tornado because it never hit anything to do that kind of damage! So then for engineering research you can only look at EF-5s that actually did EF-5 damage, and the whole wind measurement thing ends up being a waste in that scenario.

But at the end of the day, who gives a sh*t what the rating is?

Exactly my point. The only people that seem to care are the people that think Storm Data is this immaculate tome of tornado knowledge and our goal should be to make it better and accurately record everything. Trust me, I've parsed the data, stored it in a database, ingested it into code, run analysis against it, and the biggest thing that sticks out is there's a lot of bad data in Storm Data!

 

[Jake Orosi]

So, you're telling me that rating the El Reno tornado EF-5 versus EF-3 is going to directly lead to an improvement in the warning system? I did not say that researching and record-keeping is pointless. It is important. However, if 20 people are killed by a tornado, does it matter if that tornado is rated EF-3 or EF-4? I appreciate the passion on both sides of the argument, but my point is that it seems like a small thing to argue over given the death and destruction. Don't get me wrong, as a meteorologist, the final rating is important to me, but I don't have a strong feeling either way about the use of radar in determining a rating, so I'm not going to get bent out of shape. It's definitely an interesting debate, and exciting, too, because it's demonstrating a great advancement and application in technology. In the area I work, the odds of me ever having a mobile radar measurement are fairly low. Yes, I have Doppler envy. There I said it.

I guess it all depends on your audience. Maybe I'm looking at things too broadly. I tend to always look at things on the large scale. How does the vast majority of my customers, city/state/county officials, media, and the general public view this? Five years from now, the majority of the general public probably won't remember what the El Reno tornado was rated or that mobile Doppler radar measurements were used to upgrade the rating.

I, on the other hand, am interested purely in the scientific data aspect. It doesn't matter to me what or whether the public thinks about EF-ratings. EF-ratings were not designed with the public in mind, but with scientific data collection in mind.

The EF rating is a wind speed classification, not a damage classification. An Doppler-measured EF-5 tornado that has "only done EF-3 damage" because there happened to be nothing in the damage path that would've lasted through any but EF-5 winds, is an EF-5, because the rating isn't about the damage, it is about the wind speed. The damage a tornado causes is usually how we estimate the wind speed; but over time this has caused laypersons to confuse the method with the purpose. And that persisting confusion is the only reason this debate is even occurring.

The debate is in fact reminiscent of the recent brouhaha over the IAU's reclassification of Pluto as a minor planet rather than a true planet. There wasn't a single argument for Pluto's retaining planetary status that wasn't an appeal to emotion or tradition, two things which should never direct the course of scientific progress.

The prioritization of radar measurement in the classification of tornadoes by wind speed is, similarly, only being opposed with appeals to emotion or tradition. The difference is, these people are even mistaken about the nature of the "tradition".

 

[Rob H]

I, on the other hand, am interested purely in the scientific data aspect. It doesn't matter to me what or whether the public thinks about EF-ratings. EF-ratings were not designed with the public in mind, but with scientific data collection in mind.

Actually, they were designed with engineering, and public safety, in mind - as Fujita's work was funded by NRC grants in the early 1970s. Ted wanted to classify storms by strength, but the only option he had was to survey damage, so that's how the scale was designed.

The EF rating is a wind speed classification, not a damage classification. An Doppler-measured EF-5 tornado that has "only done EF-3 damage" because there happened to be nothing in the damage path that would've lasted through any but EF-5 winds, is an EF-5, because the rating isn't about the damage, it is about the wind speed. The damage a tornado causes is usually how we estimate the wind speed; but over time this has caused laypersons to confuse the method with the purpose. And that persisting confusion is the only reason this debate is even occurring.

The F scale was a damage classification with associated and *estimated* wind speeds. The EF scale was introduced to better incorporate different types of structures/materials and degrees of damage. A tornado that does "EF-4 damage" can't be directly compared to a tornado with measured winds in the EF-4 damage range because the EF *estimated* winds haven't been rigorously verified. It's apples to oranges, and that's not a useful scientific comparison.

The debate is in fact reminiscent of the recent brouhaha over the IAU's reclassification of Pluto as a minor planet rather than a true planet. There wasn't a single argument for Pluto's retaining planetary status that wasn't an appeal to emotion or tradition, two things which should never direct the course of scientific progress.

The prioritization of radar measurement in the classification of tornadoes by wind speed is, similarly, only being opposed with appeals to emotion or tradition. The difference is, these people are even mistaken about the nature of the "tradition".

I don't see how emotion factors into the decision to continue using the EF scale the way it was designed, while leaving the possibility open to enhance the scale again to account for measured wind speeds. It's not tradition, it's the science and defined schema for the way it works, and adding new data to it with minimal discussion is decidedly unscientific. People keep throwing out that not incorporating these measurements is setting "scientific progress" back, but no one can provide valid reasoning for how exactly this is repressing new discovery or ideas. The data is all still there, easily accessible to anyone interested.

 

[Jake Orosi]

Actually, they were designed with engineering, and public safety, in mind - as Fujita's work was funded by NRC grants in the early 1970s. Ted wanted to classify storms by strength, but the only option he had was to survey damage, so that's how the scale was designed.



The F scale was a damage classification with associated and *estimated* wind speeds. The EF scale was introduced to better incorporate different types of structures/materials and degrees of damage. A tornado that does "EF-4 damage" can't be directly compared to a tornado with measured winds in the EF-4 damage range because the EF *estimated* winds haven't been rigorously verified. It's apples to oranges, and that's not a useful scientific comparison.

Be that as it may; the fact is that, outside of an ad hoc method for estimating wind speed, "tornado damage" is scientifically useless data. It depends too much on factors that cannot be controlled or even objectively assessed after the fact; even separate buildings within the same vicinity can have been built out of vastly different materials and to different construction standards. This near-arbitrariness in the amount of damage caused by any particular storm may make for an interesting local historical datum; but for research purposes it is of little value beyond face - "One day there was a really bad/really weak tornado in Unluckyville. The End."

Whereas, accurate wind speed data is just as useful as any other measured atmospheric data when it comes to analyzing and modeling conditions and trends in tornadogenesis and storm intensity.

If the EF-scale is to be put to continued use, I fully expect that it will have to be modified - again, and as often as necessary - as actual measured data is able to better inform our estimates of what wind speed is capable of inflicted what kind of damage. Without those numbers, the EF scale is arbitrary and useless to everyone - even engineers.

 

[Rob H]

I completely agree that it will need to be modified in light of scientific advancement, and there's no reason it shouldn't be. If it wasn't clear, my only argument against what they've done in the past is that they're essentially saying "I'm going to assign this tornado a damage rating based on measured winds that match up with an estimated range of winds for a particular damage rating". That's what seems wonky to me. By all means, they should sit down and hash out what mobile doppler means to EF ratings and how the data should be annotated.

I agree with your argument about accurate wind speed data, but El Reno 1, El Reno 2, Rozel, and whatever other storms have had EF rating affected by mobile doppler, are in the extreme minority and will therefore not be compared against other storms with similar EF ratings where no mobile doppler data was taken, so why bother assigning an arbitrary rating? When studying tornadogenesis the sample set won't be "EF-5 tornadoes", it will be "violent tornadoes with measured winds available" which includes a much more relevant data set.

 

[Chris Nuttall]

That's not the official NWS EF-scale document though

I will edit that post to be more specific.

 

[Dan Robinson]

Here are links to quotes during talks at the Storm Chaser Convention on Saturday that will be of interest to some. These are direct Youtube links to the point in the live stream archive where the quotes are spoken:

Dr. Howie Bluestein:
http://www.youtube.com/watch?v=Kzb-AIDCGC4#t=00h39m10s

Dr. Chuck Doswell:
http://www.youtube.com/watch?v=Kzb-AIDCGC4#t=03h02m30s

From what I understand, these stream archives of the convention won't be left up permanently. I'd recommend listening to the full talks soon if you get a chance.

 

[Jeff Duda]

I was happy to see the way Chuck talked through his portion of the talk about the dangers of chasing tornadoes. I think some people (including some on this forum) need a wakeup call about getting close, especially to particularly large/violent tornadoes. If anyone can give the call, it's Chuck.