Can the pressure change or wind in tornadoes cause injury/death directly?

[Brian OConnell]

To my knowledge every known case of injury or death in a tornado resulted in some way or another from contact with a solid object or hazardous substance that was damaged or propelled by the wind (or the person being thrown into something)

But I wonder whether the wind force or pressure change could cause injury directly, I assume any wind strong enough to cause serious injury directly would come with fatal debris, making the wind force itself irrelevant, but the pressure change I am curious about, I took a SCUBA diving class in my teens, (not that long ago) and I remember being yelled at for rocketing to the surface, it turns out the instructor had me confused with someone else who was rocketing to the surface when they got scared, but the point is the the drop in pressure you experience when rocketing to the surface is EXTREMELY dangerous, even in the shallow end of the training pool

For those unfamiliar with SCUBA, the way this works is your lungs are filled with air at whatever pressure the water around you is at the time you inhaled (pressure increases linearly at a rate of 1 atmosphere for every 10 meters of depth) for example if you inhale at 10 meters down and then come to the surface the air in your lungs is pushing outward with 1 atmosphere of pressure and trying to take up 2X the space. Now if you are breathing normally and come up slowly the excess air can just come out your mouth, but if you are not breathing normally or rush to the surface the pressure in your lungs will burst your lungs and air will end up in your bloodstream, where air bubbles block blood vessels posing the same hazards as a blood clot

Both the absolute pressure differential and the change in air volume(which is proportional to percentage pressure change) matter for the dangerousness, for example going from 20 meters to 10 meters is also a 1atm pressure change, but only a 1.5X expansion because it is a lesser percentage change, so it is less dangerous than the previous scenario (but still bad)

If I remember correctly the minimum depth that could cause serious injury if you rocket to the surface and hold your breath is 1.2 meters, which would give you a 0.12atm pressure drop and a 1.12X air expansion

A storm chaser with a roof mounted weather station was accidentally struck by the 2007 Tulia TX EF2 and recorded a pressure drop of 0.19 atm in seconds with a 1.28X expansion https://ejssm.org/archives/wp-content/uploads/2021/09/vol3-3.pdf, noticeably worse than the minimum pressure change for a life threatening scuba accident

I imagine this EF2 was not the biggest possible pressure drop, so it would seem possible to be injured or killed by the pressure drop alone, particularly if you hold your breath in fear as the tornado hits you, and it would not matter if you had shelter from the wind and debris, however plenty of people have survived tornadoes, and I have never heard of such a pressure injury, so I am curious if this is actually possible

 

[rdale]

No, the pressure change is not a cause of death.

 

[Brian OConnell]

No, the pressure change is not a cause of death.

Why would the pressure change not be dangerous if it is a greater pressure change than the pressure changes known to be dangerous in scuba? I've never heard of somone dying this way in a tornado, but I'm curious what about tornadoes makes the pressure change not a hazard?

 

[rdale]

SCUBA divers are breathing air with compressed nitrogen in it, and if you come up too quick and don't give the nitrogen time to slowly release, it can cause death. So don't breath compressed air if you plan to have a tornado pass over you.

 

[RZ Fortner]

Also, you’re probably breathing fairly rapidly due to fear/adrenaline/excitement, whatever the case maybe. So you would be breathing in and out with the same pressure as it gradually changes passing over you. But I wouldn’t recommend letting one do that anyway if it was avoidable hahahahaha

 

[Ethan Schisler]

I'm gonna give a whack at this...and I may be completely wrong here. What I had learned during university is that there are different kinds of balances such as Gradient, Geostrophic, Cyclostrophiic, and Inertial (this would be where the PGF is minimal and the centrifugal and Coriolis forces are in balance). Remember the Coriolis force is about zero near the equator. This can help to explain why hurricanes/tropical cyclones don't form or cross the equator. There has been no record of one forming within 5 degrees of such.

Anyway off topic sort of. Tornadoes would be in a form of cyclostrophic balance (a conflict between the PGF and CF). PGF being Pressure Gradient Force and CF being Centrigual force. We had learned this was determined by using the Rosby number and when it exceeds 50, the system was considered to be in more "Cyclostrophic flow".

Onward to my point, with hurricanes, the destructive winds are often fueled by an intense and very tight pressure gradient surrounding the eye of the storm. This is then usually surrounded by with intense thunderstorms which help to drive those destructive winds to the surface (the eyewall).

Tornadoes, however are far far smaller than hurricanes. So the pressure gradient is likely huge over just a couple meters versus in a hurricane where the pressure, yes, does rapidly fall, but not in the order of walking a few meters to the north or east (just an example).

I'm not sure of any direct examples except for recorded data on 5/24/2011 and 11/7/2011 at Mesonets in Oklahoma and then the nearly 100mb pressure drop recorded by Tim Samaras on 6/24/2003 in South Dakota. If I understand your question, you wanted to know if a pressure drop like that could be the direct cause of death?

So far all the information I have typed up, I got from my used Synoptic and Dynamic books and an online article from PSU. I don't have a lot of information regarding pressure drops in tornadoes. However I would say that the very very intense pressure gradient inside of a tornado, likely has a driving factor into the intensity of the winds. Especially in the cases of sub-vortices which some have made hypothesis' about containing much higher winds than the actual parent tornado. So I guess it is the "chicken or the egg" discussion. Since the wind and debris cause a lot of destruction, it is technically the wind and debris that caused any unlucky party to perish; if they get hit by a tornado directly and not really a result of either directly, but indirectly through the tornado as a whole.

I think that is really splitting hairs though on determining what caused what. I think we can all agree not to mess with the windows in your house if a tornado is coming, just get to shelter. I don't think that type of rapid pressure drop alone however fleeting fast would be enough to kill a person. The wind though along with debris, would be. I'm not sure how the TIV is built, but they went through a EF3 tornado in Northeast Kansas recording winds over 170 mph on May 27, 2013 (video is on Youtube). While I'm sure their ears popped and had some difficulty hearing, nobody suddenly dropped dead inside.

Hopefully that gave some answer to your questions, or maybe it didn't. Anyone feel free to correct me if I got anything wrong, been a while since I was back in a classroom again lol.

 

[Brian OConnell]

SCUBA divers are breathing air with compressed nitrogen in it, and if you come up too quick and don't give the nitrogen time to slowly release, it can cause death. So don't breath compressed air if you plan to have a tornado pass over you.

I mean no offense here, but this comment seems to be based on 3 misconceptions about SCUBA. The first being that there is only one way to die or get hurt from coming up too fast, there are actually 3: decompression illness (what you appear to be referring to), lung over expansion (what I was referring to in my post), and squeezes (not relevant to this discussion).

Decompression illness (DCI or "the bends"), is caused by dissolved nitrogen in the diver's body coming out of solution too fast, requires pressure changes significantly greater than any recorded tornado, and requires that the low pressure lasts for a meaningful amount of time, so I do not believe tornadoes can cause this and never meant to imply that they could

I was suggesting that theoretically a tornado could cause lung over expansion, this happens when the windpipe is closed and the pressure outside the lungs drops leading to a net force pushing outward on the lung wall, which breaks the lung wall allowing air into parts of the body where it does not belong

The second myth being that scuba divers are breathing compressed air at a higher pressure than the surrounding water, this is incorrect because a scuba regulator (the mouthpiece) takes the high pressure tank air and automatically lowers its pressure to match the pressure of the surrounding water every time you inhale, meaning that the air you inhale is always at the same pressure as the water around you, scuba equipment never pressurizes the air in your lungs above the pressure of the surrounding water (if it did you would suffer lung over expansion every dive)

The third being that scuba air has more nitrogen than normal air, this is incorrect because scuba air is often regular air taken from the atmosphere with no alterations, and therefore has the same 78% nitrogen concentration as the air in and around a tornado, it is true that other gas mixes are sometimes used in scuba, but these nearly always have LESS nitrogen than air. That said, the amount of nitrogen is only relevant to the risk of DCI, nitrogen has nothing to do with the risk of lung over expansion

BTW, wouldn't winds of 170+ mph make it an EF4?

 

[Brian OConnell]

I'm gonna give a whack at this...and I may be completely wrong here. What I had learned during university is that there are different kinds of balances such as Gradient, Geostrophic, Cyclostrophiic, and Inertial (this would be where the PGF is minimal and the centrifugal and Coriolis forces are in balance). Remember the Coriolis force is about zero near the equator. This can help to explain why hurricanes/tropical cyclones don't form or cross the equator. There has been no record of one forming within 5 degrees of such.

Anyway off topic sort of. Tornadoes would be in a form of cyclostrophic balance (a conflict between the PGF and CF). PGF being Pressure Gradient Force and CF being Centrigual force. We had learned this was determined by using the Rosby number and when it exceeds 50, the system was considered to be in more "Cyclostrophic flow".

Onward to my point, with hurricanes, the destructive winds are often fueled by an intense and very tight pressure gradient surrounding the eye of the storm. This is then usually surrounded by with intense thunderstorms which help to drive those destructive winds to the surface (the eyewall).

Tornadoes, however are far far smaller than hurricanes. So the pressure gradient is likely huge over just a couple meters versus in a hurricane where the pressure, yes, does rapidly fall, but not in the order of walking a few meters to the north or east (just an example).

I'm not sure of any direct examples except for recorded data on 5/24/2011 and 11/7/2011 at Mesonets in Oklahoma and then the nearly 100mb pressure drop recorded by Tim Samaras on 6/24/2003 in South Dakota. If I understand your question, you wanted to know if a pressure drop like that could be the direct cause of death?

So far all the information I have typed up, I got from my used Synoptic and Dynamic books and an online article from PSU. I don't have a lot of information regarding pressure drops in tornadoes. However I would say that the very very intense pressure gradient inside of a tornado, likely has a driving factor into the intensity of the winds. Especially in the cases of sub-vortices which some have made hypothesis' about containing much higher winds than the actual parent tornado. So I guess it is the "chicken or the egg" discussion. Since the wind and debris cause a lot of destruction, it is technically the wind and debris that caused any unlucky party to perish; if they get hit by a tornado directly and not really a result of either directly, but indirectly through the tornado as a whole.

I think that is really splitting hairs though on determining what caused what. I think we can all agree not to mess with the windows in your house if a tornado is coming, just get to shelter. I don't think that type of rapid pressure drop alone however fleeting fast would be enough to kill a person. The wind though along with debris, would be. I'm not sure how the TIV is built, but they went through a EF3 tornado in Northeast Kansas recording winds over 170 mph on May 27, 2013 (video is on Youtube). While I'm sure their ears popped and had some difficulty hearing, nobody suddenly dropped dead inside.

Hopefully that gave some answer to your questions, or maybe it didn't. Anyone feel free to correct me if I got anything wrong, been a while since I was back in a classroom again lol.

I'm asking if a pressure change like the one recorded here https://ejssm.org/archives/wp-content/uploads/2021/09/vol3-3.pdf (significantly greater than that recorded by samaras) could cause lung overexpansion injury (which can be fatal) the reason I suspect it could is because it is a larger pressure change than the minimum considered dangerous in scuba diving.

The fact that some people have survived in the central low pressure core of tornadoes does not mean the pressure change could not cause death, as not all tornadoes contain pressures this low, and not all people who experience dangerous pressure drops die or are injured, it depends on wheather your windpipe is open or closed at the moment of pressure drop, my scuba classmate was fine every time he panicked and rocketed to the surface, but it was still risky enough to get him a stern warning from the instructor

Most of your comment appears to be saying the wind driven debris would kill anyone in the low pressure part of a tornado, and therfore the effect of pressure itslef is irrelevant. However, the chaser who recorded the record pressure drop was not seriously injured by debris, so I'm wondering if someone in a situation like this could suffer lung overexpansion?

The distinction between debris impact and lung overexpansion would also be very relevant to medical treatment in cases that were not immediately fatal

 

[Ethan Schisler]

I'm asking if a pressure change like the one recorded here https://ejssm.org/archives/wp-content/uploads/2021/09/vol3-3.pdf (significantly greater than that recorded by samaras) could cause lung overexpansion injury (which can be fatal) the reason I suspect it could is because it is a larger pressure change than the minimum considered dangerous in scuba diving.

The fact that some people have survived in the central low pressure core of tornadoes does not mean the pressure change could not cause death, as not all tornadoes contain pressures this low, and not all people who experience dangerous pressure drops die or are injured, it depends on wheather your windpipe is open or closed at the moment of pressure drop, my scuba classmate was fine every time he panicked and rocketed to the surface, but it was still risky enough to get him a stern warning from the instructor

Most of your comment appears to be saying the wind driven debris would kill anyone in the low pressure part of a tornado, and therfore the effect of pressure itslef is irrelevant. However, the chaser who recorded the record pressure drop was not seriously injured by debris, so I'm wondering if someone in a situation like this could suffer lung overexpansion?

The distinction between debris impact and lung overexpansion would also be very relevant to medical treatment in cases that were not immediately fatal

The chaser who recorded the pressure drop in the June 24, 2003 Manchester, SD F4 tornado was using a probe, therefore he was not IN the tornado when it impacted it. The other cases were instances of mesonet sites being impacted, also where nobody would be standing to get impacted by those winds. As far as the article you cited, considering that pressure recorded was quite a bit deeper, I'd say the pressure probably isn't causing death or lung overexpansion. I don't think anyone can say for certain though given the very limited data we have and few first hand experiences we have to go on.

People go skydiving though all the time at an average altitude of 10,000 feet which is 696.817mb roughly, many don't use any type of oxygen at that level and are perfectly fine after opening the door to the plane from being pressurized to the outdoor environment. I've never been myself, but that is just my guess.

 

[Brian OConnell]

The chaser who recorded the pressure drop in the June 24, 2003 Manchester, SD F4 tornado was using a probe, therefore he was not IN the tornado when it impacted it. The other cases were instances of mesonet sites being impacted, also where nobody would be standing to get impacted by those winds. As far as the article you cited, considering that pressure recorded was quite a bit deeper, I'd say the pressure probably isn't causing death or lung overexpansion. I don't think anyone can say for certain though given the very limited data we have and few first hand experiences we have to go on.

People go skydiving though all the time at an average altitude of 10,000 feet which is 696.817mb roughly, many don't use any type of oxygen at that level and are perfectly fine after opening the door to the plane from being pressurized to the outdoor environment. I've never been myself, but that is just my guess.

Lung overexpansion depends on whether the windpipe is open or closed, the fact that the chaser survived the 192 mb pressure drop could have been because his windpipe was open at the time of the pressure drop

As for skydiving, those planes are not pressurized, so opening the door does not cause a sudden pressure drop, the pressure instead drops gradually as the plane rises Skydiving and Your Ears - Skydiving With a Cold | Skydive Carolina

 

[Jeff Wright]

The pressure drop isn’t the big worry.
The Jarrell event started as an uber drill bit tornado. If one were lashed to the top of an overpass, I could see a narrow funnel perhaps tearing flesh?

 

[rdale]

I was suggesting that theoretically a tornado could cause lung over expansion, this happens when the windpipe is closed and the pressure outside the lungs drops leading to a net force pushing outward on the lung wall, which breaks the lung wall allowing air into parts of the body where it does not belong

Offense not taken, but again theoretically and realistically there's no way for this to happen. Who holds their breath during the entire timeframe a tornado passes overhead?

 

[Brian OConnell]

The pressure drop isn’t the big worry.
The Jarrell event started as an uber drill bit tornado. If one were lashed to the top of an overpass, I could see a narrow funnel perhaps tearing flesh?

The debris could of course, but even 457 mph wind has been proven not to damage skin This Is What 457 MPH Wind Will Do to Your Face Although I would be concerned what would happen if he opened his mouth or took off his goggles

Debris is by far the main hazard, the Tulia pressure data just made me wonder about pressure causing problems in certain specific situations

 

[Brian OConnell]

Offense not taken, but again theoretically and realistically there's no way for this to happen. Who holds their breath during the entire timeframe a tornado passes overhead?

Some people hold their breath for a second or 2 when scared, and most of the pressure drop in the Tulia tornado looks like it occurred in 1 second

 

[rdale]

Some people hold their breath for a second or 2 when scared, and most of the pressure drop in the Tulia tornado looks like it occurred in 1 second

If they held their breath for two seconds while getting hit by a tornado that tried to suck the air out of their bodies but it didn't harm them from the winds, then they would exhale even if unintentionally.

 

[Brian OConnell]

If they held their breath for two seconds while getting hit by a tornado that tried to suck the air out of their bodies but it didn't harm them from the winds, then they would exhale even if unintentionally.

At that point what does it matter if they exhale? A diver who rockets to the surface will exhale too, but the damage is already done

 

[rdale]

At any point - the force of holding your breath cannot exceed the force of the air pushing out of your lungs.

No death.

 

[Brian OConnell]

At any point - the force of holding your breath cannot exceed the force of the air pushing out of your lungs.

No death.

This is factually wrong, scuba divers can and do suffer potentially fatal rupture of the alvioli if they hold their breath during pressure changes that are less than the pressure change in the tulia tornado https://dan.org/alert-diver/article/lung-expansion-injuries/

 

[rdale]

You are referring to divers - we are discussing the tornado survivor.

They will live.

 

[Brian OConnell]

You are referring to divers - we are discussing the tornado survivor.

They will live.

What is the significance of this distinction? The pressure change is what is dangerous, and the tulia tornado had a greater pressure change than that known to be dangerous to divers

 

[RZ Fortner]

I honestly don’t know, I’m not a scientist. But I’m sure there is an explanation of why I’ve never heard of a pressure drop death from a tornado. Yet you do from scuba divers.

 

[Brian OConnell]

I honestly don’t know, I’m not a scientist. But I’m sure there is an explanation of why I’ve never heard of a pressure drop death from a tornado. Yet you do from scuba divers.

In the absence of any other explanation I would have to assume it is possible, but has never been reported by chance

This would only happen if the tornado was small and fast enough to cause the pressure to drop in a couple seconds, the center of the tornado passed directly over the victim, the victim had their windpipe closed at the moment of tornado passage, and the tornado had extreme low pressure, which may only occur in the most extreme EF5s (likely fatal regardless of pressure) and for a brief time during corner flow collapse of moderate tornadoes, these factors make the probability of someone encountering such a danger low, even in a tornado, but it is still a risk, perticularly for those who intentionally put themselves in tornadoes over and over (TIV, ect) it is also possible that this has happened at some point but the cause of death not recognized due to other traumatic injuries that were assumed to be the cause of death

 

[rdale]

It really isn't something to worry about. There's no evidence that it is a risk.

 

[Brian OConnell]

It really isn't something to worry about. There's no evidence that it is a risk.

I'm not worried about it, the question was more about scientific curiosity than concern for my safety, I'm not planning on going inside any tornadoes

That said I do think the pressure change recorded in a tornado being greater than the pressure change that is dangerous to divers constitutes evidence that this is a risk in very specific uncommon scenerios

 

[rdale]

Oh okay - thanks for clarifying. So far there is no evidence or data to back up that claim, but I encourage you to experiment if you can do so safely!