We've already seen category 6 hurricanes – scientists want to make it official | Hacker News Reader

We've already seen category 6 hurricanes – scientists want to make it official

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260 pointssohkamyung164 comments

I am skeptical of this paper. If you go to Wikipedia's list of most intense tropical cyclones[1] and sort by barometric pressure, there doesn't seem to be much correlation with time. The biggest and most intense tropical cyclone is still Typhoon Tip in 1979.[2] If you read the actual study[3], it looks like they do a lot of data manipulation and simulation to come to their conclusion. They subtract 15 meters/sec from wind speeds measured before 1973, claiming a bias in measurements from that time. This causes a huge step up in lifetime maximum intensity in the 1970s. Their estimates of future category 6 probabilities are from simulations that they admit don't simulate current conditions correctly.

I think it's more likely than not that tropical cyclones are getting more intense, and that they're hitting places that didn't typically get hit in the past, but I don't find this paper convincing. It really feels like they cajoled the data to fit their conclusion.

1. https://en.wikipedia.org/wiki/List_of_the_most_intense_tropi...

2. https://en.wikipedia.org/wiki/Typhoon_Tip

3. https://www.pnas.org/doi/full/10.1073/pnas.2308901121

In fairness though, they didn't just make up their bias assertion; it's in other published works[1] and there is real evidence that old measurements were incorrect (biased towards the high side) when compared to other available contemporary measurements.

[1]: Landsea, C. W. Mon. Weath. Rev. 121, 1703–1714 (1993) - https://journals.ametsoc.org/configurable/content/journals$0...

Their corrections may be correct, but it's still always nicer when the magnitude of the signal is larger than that of the corrections to the data.

What is nice is vetting and correcting data for reliability and consistency.

Part of aiming for objectivity, and better understanding, isn't worrying about which direction a correction takes. At all. Only that it is a good correction.

Our brains constantly make up distracting narratives, if we let them.

If the correction had been the other way, some people would say scientists have been downplaying data and probably still are.

> Part of aiming for objectivity, and better understanding, isn't worrying about which direction a correction takes. At all. Only that it is a good correction.

I don't think you fully grasp the implications of arbitrarily correcting old measures. In the end, and accepting at face value these corrections, you're still manipulating old data to use the result of said manipulation as the whole basis of your hypothesis.

This approach automatically leads to questions on whether you draw your conclusions from the data, or you change the data to fit your conclusions.

Do you understand the risk that this poses in any discussion on a politically sensitive topic?

Think of the hit to the credibility of any claim supported by this data manipulation if later your method is deemed untrustworthy because it needs further updates, and how it would look if you had to correct it to move the dial either way (i.e., "they were lying from the start and are now covering their ass" vs "they felt their lie wasn't fooling anyone and decided to double down.")

The point was that the corrections aren’t arbitrary.

> The point was that the corrections aren’t arbitrary.

But they are, aren't they? It matters nothing if you apply a precise rule to change values. What matters is that you picked a rule.

> arbitrarily correcting old measures.

Why do you say the correction is arbitrary? Are there papers arguing for corrections in the other direction?

> Why do you say the correction is arbitrary?

Because it follows a method picked and chosen by the corrector.

> Are there papers arguing for corrections in the other direction?

It doesn't really matter if these corrections sway one way or the other. What matters is that someone decided that the original values weren't good, and proceeded to pick a way to come up with other values by changing the original ones.

I still don't understand your choice of words. It feels like you jumped into epistemology at the deep end and don't know how to swim in it. One article that pops up frequently around here is "Reality has a surprising amount of detail"

http://johnsalvatier.org/blog/2017/reality-has-a-surprising-...

I think you could profit from reading it. And I found "The Golem" a pretty good read too, if you want to go down that path:

https://www.cambridge.org/ch/universitypress/subjects/genera...

Tough shit. Nature doesn't care about political inconvenience. You must work with your most accurate representation of the data.

I wonder how these comments measure on the Henderson Scale of plot-derailment.

> It really feels like they cajoled the data to fit their conclusion.

(Emphasis mine.)

That Guy!

To add to the "not arbitrary corection" comments.

Correction is also not lying. Anyone who states that is not grasping something about a totally political topic/method.

It’s just reductionism: if changing data is bad, changing data is always bad.

Same nonsense gets you how terrible surgeons are (if cutting people with knives is bad, cutting people with knives is always bad).

It’s a good rhetorical technique because if you remove enough context you can pretty much always find something “exactly the same” to prove a point.

> It’s just reductionism: if changing data is bad, changing data is always bad.

It's not reductionism, and you're missing the point.

The whole point is that changing the original data to be able to support/reject hypothesis naturally raises the question of whether there is foul play.

If original measurements don't support your claim and suddenly by changing data you get it to fit your belief, any rational analysis would quickly flag the risk of data manipulation and scientific malpractice.

If instead you're dealing with a politically charged topic that attracts denialists and contrarians then you're making yourself vulnerable to accusations of fraud that will certainly be used to poison the well.

Do you understand why this is a problem?

> The whole point is that changing the original data to be able to support/reject hypothesis naturally raises the question of whether there is foul play.

People are applying a stronger point here where changing the original data is hard evidence of foul play and sufficient to completely discount any changes.

We'd be grappling with the reality of faster than light neutrinos now, though, if that was correct logic.

> People are applying a stronger point here where changing the original data is hard evidence of foul play and sufficient to completely discount any changes.

Manipulating field measurements is already frowned upon in all applications. There is no point. Things like data provenance is a serious issue, which is directly targeted by peer reviews and investigations on scientific malpractice. Even performance benchmarks highly favor standardized test and data sets.

Being objective matters. Once you start messing with original measurements, you place yourself in a position where you need to answer questions on whether you're just adapting data to fit your belief instead of the other way around.

In this case there is an observable relationship between wind speed and central surface pressure which has been observed over decades, but it has changed between the 1950s and the current day (although it has been stable across recent decades). The difference is in the measurement of wind speeds and with modern dropsondes we have much better measurement of wind speeds than existed in the 1950s. There is a clear and consistent bias in the windspeed-pressure relationship between decades. The correction that has been applied has been to apply a bias to correct the wind speed to the central pressure measurement. That correction was proposed in 2005 and so is nearly 20 years old at this point and had nothing to do with the current paper on cat 6 storms.

> The whole point is that changing the original data to be able to support/reject hypothesis

How do you know this? Do you understand the reasoning behind bias correction?

> Do you understand why this is a problem?

The problem is people do not understand bias correction and you are certainly not arguing on a methological level.

I could be wrong but I read your post as saying "politics can't deal with progress in scientific insight into the observable universe, thus scientists better be careful what they say." That's medieval. We are better than that... or at least we used to be. Otherwise the sun would still rotate around the earth.

Yup it’s a good way to make it fit the narrative and get more funding.

While I like a good conspiracy, it seems to me as though this was a perfectly appropriate outcome of technological advancement. Surely old storms would be biased high given a variety of reasons.

It's been acknowledged in the meteorological community that reconnaissance wind speed estimates for storms in the 1950s and 1960s have a high bias in the most intense storms, as the field was still in its infancy during that time period. Further advancement in later decades has improved the confidence in the estimates.

No conspiracy needed. After all, the first time a hurricane was intentionally flown into by a storm was only in 1943: https://en.wikipedia.org/wiki/1943_Surprise_Hurricane. The 1950s and 1960s are not that far removed from that initial attempt.

They do the same thing with temperature readings.

Don’t say that. You will get called a climate denier.

Precision of temperature readings improved over time

From the paper:

> "...of the 197 TCs [tropical cyclones] that were classified as category 5 during the 42-y period 1980 to 2021, which comprises the period of highest quality and most consistent data, half of them occurred in the last 17 y of the period (12). Five of those storms exceeded our hypothetical category 6 and all of these occurred in the last 9 y of the record. The most intense of these hypothetical category 6 storms, Patricia, occurred in the Eastern Pacific making landfall in Jalisco, Mexico, as a category 4 storm. The remaining category 6 storms all occurred in the Western Pacific... Fig. 1A shows these 5 storms on the existing Hurricane Wind Scale and our proposed extension."

https://www.pnas.org/doi/full/10.1073/pnas.2308901121

Theoretically, increased wind speeds are linked to increased sea surface temperatures, a warmer deeper ocean mixed layer, and more moistore in the atmosphere. However, increased vertical wind shear tends to break up the hurricane's chimney structure, and that might also increase with warming. Hence, a complicated prediction - but if conditions are right, it seems reasonable to conclude that unusually strong hurricanes will become more likely, even if overall frequency is unchanged.

> Hence, a complicated prediction - but if conditions are right, it seems reasonable to conclude that unusually strong hurricanes will become more likely, even if overall frequency is unchanged.

Not really, its not caused by warm water, its caused by DIFFERENCES in the temperature from the water and air, which is why we have actually seen fewer hurricanes over the last 20 years (ignoring post 2020 because this decade doesnt have a lot of data in) source: https://www.nhc.noaa.gov/pastdec.shtml

Its hard to decide when picking a particular category, so what I did was charted category 1s + 2* category 2 + 3 * category 3 ...

Warmer water will put more water vapor into the air, which will provide more energy, even if the difference in temperature between water and (upper atmosphere) stays the same.

> I think it's more likely than not that tropical cyclones are getting more intense, and that they're hitting places that didn't typically get hit in the past

I think so too. One measure is the amount of insured losses from hurricanes. There's been an uptick in number of hurricanes and other weather events causing more then a billion dollars in insured losses- that's simply correlated with the increase in the value of insured assets.

Even if we assume that storms are not getting more intense, or climate is not changing, we cannot deny that we have more valuable assets to protect now. Which requires climate actions.

Was this adjusted for inflation?

"Even if this study is a lie, and storms are not getting more intense, we will still need to take your right to drive a car"

There's no need to strawman. Even if storms weren't getting stronger we'd still have to contend with rising sea levels and the loss of arable land just for starters. While it would be ideal to live in a state of progress such that most folks didn't own nor operate a vehicle there is no credible threat at this point toward not being able to own and operate a vehicle.

>While it would be ideal to live in a state of progress such that most folks didn't own nor operate a vehicle

No it wouldn't. It is ideal to live in a state of progress where most "folks" can afford to own and operate a vehicle that allows them to go wherever they want whenever they want and take people with them.

The US has followed this as a guiding principle over the last hundred years and largely succeeded, however the end-state seems to be a built environment where car ownership is not simply a widely enjoyed privilege so much as a de facto requirement to go about the activities of daily living, which feels, at least to me, somehow less free.

If they can accomplish the same things with more efficient public transportation, then that seems like it would be progress.

Why is that “progress?” Why is “progress” a good thing in its own and who decides what “progress” even is?

I addressed that in my post. In this case I'm using progress to mean accomplishing the same thing with less resources. It's not a good thing on its own, it's a good thing because resources are limited and expending those resources tends to produce pollution.

Only that you are not accomplishing the same thing. You are accomplishing something inferior. And please don't make me explain to you how you don't get, by far, the same level of service, the same amount of destinations, 24/7 availability, etc with public transportation than with your car.

When I lived in NYC, the experience of using public transportation was far superior to the experience of driving. I didn't have to purchase and maintain a car, I could read or use my phone during the trip, when I went out with friends I didn't have to worry about a designated driver, I could travel late at night when I would be too tired to drive safely, in the winter I didn't have to spend half the trip in a cold car, my risk of injury during my commute was much lower, etc.

1. Most people do not live in New York. I live in Seattle and driving is not a problem except for an hour at the end of the day.

2. Public transportation comes with its own set of risks. It is up to the individual to determine what they wish. Neither option is “progress” it is a trade off.

If you read back, this discussion was about a scenario where most people don't need to own or operate their own car. That implies that they would live in a place with good public transportation like New York has now.

Arguing over the semantics of the word "progress" is missing the point. There are very real problems with building society to cater to individual private car ownership. Instead building society to cater to public transportation would address those issues. If you see a different way to address those issues than why not present it?

You aren’t accomplishing the same thing, you are providing less tailored experience and calling it progress because you believe your opinions are progress and any others are regressive. Thanks for proving that

Instead of resorting to personal attacks, why not present a counter argument?

How is no independent mobility progress?

People don't have independent mobility now. The majority of cars are not designed for off road and therefore can only go where there are streets. If public transportation provides the same access, then there is no loss of mobility.

Well yes, but in 99.9% of cases, there are roads to where you want to go. Public transport is not independent. Live in a rural area? Fsck you, no bus/train for you. Have a large dog? Nope, no transport for your dog. Want to travel at 3 in the morning? Nope. Need to carry stuff with you, more than you can carry? Nope. Want to go to a protest? Nope, no buses/trains driving there today.

That's why the post that started all this expressed a desire to live in a future where people could replace their cars with public transportation as opposed to advocating that we get rid of all cars now. Currently public transportation isn't viable for many people, but it would be nice if in the future it was.

That being said, I think that you are overstating some of the limitations of public transportation. The NYC subway runs 24 hours, allows dogs, I have taken it while transporting 200 lbs of steel before, and it did not stop running during the George Floyd protests (including after curfew).

I live ON the beach, and the beach hasn't changed one iota in the past 40 years, other than a loss of the scarp during / after large hurricanes. The TV "science" is becoming so ridiculous that it's hard to fathom that there are people who actually believe it.

Am I to believe that there is one large, interconnected ocean, and that fluid naturally levels itself out, but that also, somehow, certain places experience sea level rise while others don't? Is it some huge coincidence that the places experiencing extreme sea level rise (e.g., Solomon Islands) are ephemeral and ever-changing volcanic islands and other volcanically active regions that sit upon a soft foundation of molten mantle?

Use your brain, my friend.

There is absolutely no possible way that you (or any other person) would notice a 4 inch GLOBAL AVERAGE rise in sea level over the last few decades. I don't care if you literally spent 24 hours per day, 7 days per week, 365 days per year on your belly at the high tide mark.

The data is the data and you need a lot more than "living on the beach" to refute it.

And yes, the sea level is different in different parts of the Earth. Why? Because forces are different in different parts of the Earth. Current (which impart forces) alone is enough to make a difference in sea level in two different parts of the Earth.

And yes, land changing elevation is colloquially part of sea level rise.

The problem with using your brain is it doesn't make you an expert in things, or able to refute expertise without actual knowledge. And simple observations do not amount to much knowledge on anything but the most simple subject.

Absolutely no way huh? There are literally corals (East Florida rock reef) that are barely covered in water at high tide, and these same corals were the same amount covered in 1988. I would notice. I would also notice my best friend's seawall become inundated every high tide now. I know these things are uncomfortable to hear, because a panel of dubiously grant-funded "scientists, who otherwise do nothing but produce irreproducible white papers, said differently.

4 inches is no joke for a small Florida beach town. It's not like California, where you have 80 foot cliffs and wide beaches. My favorite childhood beach spots would have been halved. Instead, they're exactly the same. 4 inches would have ruined much of our town's waterfront property.

Go look up pictures from Liberty Island, 1918. The water level is at the same brick as it is at high tide today.

Global warming is a false religion.

Given how vehemently wrong you are I can only imagine you don't understand what's being communicated and don't want to learn what's being communicated.

> Go look up pictures from Liberty Island, 1918.

    "The most obvious problem with the pics is that unless they were taken at the exact same point in a tidal cycle they say nothing about average sea level rise,". Raymo said that the old photo could have been taken near high tide and the recent photo could have been taken near low tide. We just don’t know.

All one needs to do, in order to prove the theory correct, is to take a new photo at a high springtide[1]. If it's no higher than the old photo, then the theory is correct. If it is higher, then we don't know (because the old photo could have been taken at a lower tide).

Ultimately, it doesn't matter. Without any disrespect intended, anybody, who thinks the ocean is meaningfully rising because of human activity, I'd rather not have living in my town; they're likely to vote to raise my taxes because the TV told them that if they give money to the government the weather will be gooder.

1. https://www.tideschart.com/United-States/New-York/New-York-C...

Surely you would suspect any photo of being photoshopped?

Satellites take millions of "photos" around the world every day, and combined with local measurements, we have a pretty accurate record of how the sea level around Manhattan has changed over the last century: https://sealevel.info/MSL_graph.php?id=8518750&c_date=1900/1...

> Without any disrespect intended, anybody, who thinks the ocean is meaningfully rising because of human activity, I'd rather not have living in my town;

Without any disrespect, perhaps you would think differently if you'd had a career in exploration geophysics for mineral resources and energy spanning a few decades as I have had.

I started out with continent wide surveying to peg old pre-GPS maps to WGS84 and have worked on mapping the global magnetic field, the geoid (mean 1G gravity surface), continent wide tidal models and radiometric references, etc.

It's clear enough that human activity is causing more heat energy to be trapped in the lower atmosphere and upper sea levels, the artic and antartic are slowly shrinking back .. and none of this is as yet readily perpectabe to the casual human eye - good instrumentation and records tell a different story, as was peer linked in a comment here.

I have little interest in convincing you, this is just a factual statement of my experience and yourself and your town can continue to believe whatever you collectively choose - it has zero impact on what is actually happening and what the next generations will have to deal with as a result of a century of excessive fossil fuel consumption.

A new generation has come up since Al Gore's fictional movie from 2006, presumably starting production in 2005. I have seen zero evidence of the predicted calamitous events that would distiguish this day from those in 2005. however I have seen the evidence of widespread problems in children who are having nighmares of a future "planetary emergency" which never seems to arrive. If children with emotional problems are the preferred social outcome of this political science, then the science is a success

Sea levels are rising primarily because the sea is warming, and water, like most substances, expands as it heats up.

Global warming does not affect every place on Earth evenly, that's partly why the phrase "climate change" is preferred. It's possible that you live in an area that due to the local or regional geography, the sea level has not changed much.

Bruh.

With tornadoes the traditional F(Fujita) classification is based on how much damage the wind does. There is a correlation to windspeed. but the final verdict is based on damage done.

https://en.wikipedia.org/wiki/Fujita_scale

https://en.wikipedia.org/wiki/Enhanced_Fujita_scale

Why have categories at all. Just use stats.

Stats, like wind in miles-per-hour? That seems arbitrary. Why not just use wind speed in plank-lengths per zeptosecond, then?

It's almost as if expressive abstractions are helpful for human understanding of large sets of numerical statistics, no?

nobody knows the difference between four and five and three and two. Its always on the news as a "warzone". so a real energy number would be nice.

A total energy level could help with total damage predictions, but, for the individual, wind speed and storm surge are key.

> they're hitting places that didn't typically get hit in the past

The human population is four times larger than it was in the 1970's, so there's more things to hit are they are often built in more marginal locations.

Can you clarify?

Are you saying that locations of the hurricanes have not changed, it's merely that there are now people/structures there so it's now noticeable? Or that humans are altering storm paths based on structural changes to the environment?

Just making the observation that there are more humans and a larger built environment. When there is a natural disaster, there's likely to be more human impacts now than 50 years ago, regardless of the location or cause.

Mostly the former. with more developed coastline and more people living there, more damage is going to happen. Could storms be altered by human activity? Sure, but it's very difficult to reconcile how much is human action vs a hurricane making landfall in an area that wasn't urban 50 years ago.

> The question of whether a category 6 would be an effective communication tool requires a larger discussion, with input from social scientists, psychologists, emergency managers, and city planners, Kossin said.

Or, communications professionals! I would love to see more emphasis on science communications.

The article touches on the fact that the Saffir-Simpson scale kinda over-relies on arbitrary windspeeds as its categorization factor. It doesn't take into account the potential damage from storm surges and flooding. (Also, as the comedian Ron White has remarked, it's not that the wind blows, but what the wind blows.[1]) Does a human have any way of conceptualizing the difference of 178-208 km/h (cat4) versus 252+ km/h (cat5) hurricane? Instead, there's an over reliance on the number -- perpetuated by how news media portray the storms.

In October 2023 residents of Acapulco, Mexico were told that a Category 1 hurricane was approaching. It rapidly intensified to a cat 5 within a day and residents were totally unprepared.[2] Did residents even know "rapid intensification" was even possible?

Is the potential for rapid intensification due to warming waters the thing we should be communicating rather than "category numbers"?

In 2007 they updated the 'Fujita Scale' for Tornadoes (Now the 'Enhanced Fujita Scale') to better incorporate assessed damage.[3] Do we need some sort of update to the Saffir-Simpson scale that better takes into account potential/assessed damage? (Especially as it relates to the flooding/storm surge aspects).

[1] https://www.youtube.com/watch?v=RQD7Fzid1xI

[2] https://disc.gsfc.nasa.gov/information/data-in-action?title=...

[3] https://www.weather.gov/oun/efscale

edit: In terms of what the wind blows: an equivalent category storm that hits Jamaica versus one that hits Houston will likely produce very different levels of damage purely due to the difference in infrastructure types. Yet, both regions are warned with the same "category number."

This is also similar to the difference between Moment Magnitude vs Modified Mercalli or Shindo.

https://en.wikipedia.org/wiki/Moment_magnitude_scale

https://en.wikipedia.org/wiki/Japan_Meteorological_Agency_se...

You want wind Sieverts, not wind rads

Category 1 - 74-95 mph

Category 2 - 96-110 mph

Category 3 - 111-129 mph

Category 4 - 130-156 mph

Category 5 - 157 mph or higher

I’m not sure why these divisions were made. The jumps between are seemingly arbitrary, from 27 mph to 15 mph and no pattern I can discern. What makes the next jump to 192 which is the largest jump yet?

Like Fujita scale for Tornados, it's about potential for potential damage it can cause which is here dependent somehow on the wind speed variable. I'm sure someone more knowledgeable about it can explain how it's correlated, but it's not about wind speeds (alone).

Reminded of a joke by Ron White in the context of a person choosing to remain behind in a hurricane because they believe they can withstand the wind and rain: “It’s not that the wind is blowin’, it’s what the wind is blowin’.”

On topic, it makes me wonder if the wind cutoffs have to do with what can be additionally picked up by the increase in energy. I’d honestly assume not but I would still hesitate to assume that it’s arbitrary. Not really sure but the phrasing of the joke made me wonder.

This made me interested as well. Why the exact cut-offs, right?

I found few resources like NOAA https://www.nhc.noaa.gov/pdf/sshws.pdf and wikipedia https://en.wikipedia.org/wiki/Saffir%E2%80%93Simpson_scale saying basically about the wind speed that the actual wind speed is "sustained winds as average winds over a period of one minute, measured at the same 33 ft (10.1 m) height" and then I thought ok if this scalar we're using is correlated to potential damage, that would mean force, right? They did remove air pressure and storm surges as components later on. I didn't bother with air pressure outside of standard since it would deviate a lot into researching exactly that.

Since it's not really my domain, I decided to wing it by googling around and looked for wind force formulas. One that I found out ( https://sites.uci.edu/energyobserver/2017/09/07/hurricane-wi.... ) can roughly be translated as F = v^2 but then when I charted it out with x being wind speed and y proportional force, only thing I found out was that it looked logarithmic (which I didn't need a chart for lol ).

The other I found was saying for wind load formula "The generic formula for wind load is F = A x P x Cd where F is the force or wind load, A is the projected area of the object, P is the wind pressure, and Cd is the drag coefficient." I had to hunt for variables here, but gist of it is that since scale is in mph I went USA with 1 square foot for A - area (and then to square meters from that, 0,093 m^2), wind speed to m/s, and went with these (more googling): Wind Pressure (P) is P = 0.5 x p x V^2 where p (rho actually) is air density (google: 1.225 kg/m^3 at sea level and 15C, I couldn't find one at 10m height), V is our wind speed, and Cd (drag coefficient) for a flat plate which is 1.28 according to https://www.grc.nasa.gov/www/k-12/VirtualAero/BottleRocket/a....

tl;dr; I couldn't find clear cuts in Newtons. I tried minimum, maximum and average wind speeds for each categories, and then I kind of lost interest there. More googling says that it was based on established observations what wind force can do to structures, but no more than that and I couldn't source original work to see more details.

Outside of optics, this is as far as my physics will lead me tonight. I'd be highly interested to see if anyone more in the know can provide methodology behind it, be it from meteorology, construction, or fluid dynamics.

Yeah, you know that's not a bad idea... just label the Category by what is being blown around in the wind.

   Category 1: Trash Cans and Patio Furniture
   Category 2: Shingles and Gardening tools
   Category 3: Branches and Bricks
   Category 4: Small vehicles and mobile homes
   Category 5: Lage vehicles and houses
   Category 6: Full concrete Trucks and and Roads

I once traveled ('97) to go see the damage done by an F5 tornado and what struck me was that a 50ft wide section of asphalt roadway had been removed where the eye had passed. Granted that is about 270mph, but I would still be worried about depressurization even in a bomb shelter.

Category 7: Hospitals and skyscrapers

Category 8: Small continents

Category 9: Other hurricanes

Category 10: Your mom

You're getting downvoted but this gave me a chuckle

The thing I find interesting (in a way) is that even then, the damage caused is not a single-variate function.

Where I live, we just had a massive for the area storm with really strong wind gusts. My little weather station on my balcony recorded 80mph gusts. I also have several new cracks in the walls from when the roof tried to leave the building. But in other places, hurricanes and tornadoes much stronger than that still end up leaving buildings intact.

We try so hard to reduce so many things to a single number, a single qualifier. And nature just keeps showing us why that's not entirely useful.

Musings from an evening spent in the dark, and perhaps the slightly spoiled leftover meatloaf that I had because there was no power to cook anything.

I think its the damage that benign debris can do to a person at certain speed thresholds

but I could be wrong

which seems weird when you consider the building materials and styles that different regions use.

It’s an extension of the Beaufort scale. The start of class 12 aligns with the start of cat 1.

That's a partial answer, but not the full story.

The Beaufort scale is designed to grow as B^1.5, and so it has a natural direct extension. 13-16 on the extended Beaufort scale do not map onto category 2-5 (https://en.wikipedia.org/wiki/Beaufort_scale#Extended_scale). As others mention, SSHWS was designed to reflect building damage.

Apparently, Saffir's original scale only included wind speed; Simpson augmented it to include storm surge and flooding. However, the categories were at times conflicting (e.g. Hurricane Charley in 2004 was a category 4 that led to a storm surge of 7 feet, or Katrina that made landfall as a category 3 but led to a storm surge of 20+ feet in places). To reduce public confusion, the NHC simplified the scale to only use a single prescriptive factor, wind speed (oddly, while still keeping Simpson's name attached to the thing even though they removed his contribution).

https://www.nps.gov/articles/saffir-simpson-hurricane-scale.... contains the multi-factor scale that was discontinued in 2009.

They are indeed completely arbitrary, which makes "Category 6" completely meaningless/useless, just like the rest of those silly numbers. A storm with a wind speed of 130 mph is not 20% more dangerous than a storm with wind speed of 128 mph. They are equivalent dangers. It's a ridiculous system and should be abolished, but it won't, because it's good entertainment.

Oh come on, by that criteria you dismiss the entire concept of categories.

Rounding is not a disqualifier.

Something being arbitrary doesn’t make it meaningless. It’s arbitrary and useful, so people use it.

It's supposed to be roughly correlated to damage potential to man made structures. It is also supposed to be logarithmic.

https://www.nhc.noaa.gov/aboutsshws.php

As a wertern European, the first time I converted wind speeds from a US hurricane, I thought I fumbled the maths, it was like 100kph/60mph higher than our winter storms. I since learned that the storm scale and the hurricane scale are different, and we simply don't have hurricanes here, we never see real crazy wind speeds and we don't use the hurricane scale at all.

The aftermath of a hurricane is like nothing you've ever experienced - there's something deeply unsettling about all the trees in a forest being bent uniformly in one direction, or entire neighborhoods completely erased. 285 km/h sustained winds comes out to roughly 3.8 kpa pressure on all surfaces. So for every 1m^2 of surface area perpendicular to the wind direction, you're getting ~350kgf applied.

In the Pacific Northwest, we get extra bad wind storms around every 30 years. The storm in 1993 was 60-75 mph and going back to 1921 a storm was 115 mph with gusts to 150 mph. What's it like in Western Europe?

I'd say Lothar was a very big recent one, https://en.wikipedia.org/wiki/Cyclone_Lothar (albeit the name, cyclones don't develop if the ocean water is less than 26°C, and let me tell you that there was a solid 15-20°C margin in the zone).

Germany had some solid gust speeds, but when you look at France, it's not biting that much in the 100mph.

Hurricanes require big patches of warm ocean to feed on--they can leave such areas but they will weaken with time if they don't have warm ocean to feed on. Furthermore, northern-hemisphere hurricanes will in general move northeast, your water is to the west.

You get the rare EF3 or EF4 tornado in western Europe that have hurricane wind speeds.

I just happen to be reading Peter F. Hamilton's Confederation universe (1996–2000) trilogy and in it earth has been dealing with the "Armada storms" for a couple hundred years due to climate change. From the descriptions there are multiple of these storms occurring at any given time. Humans now live in "arcologies" which are giant multi-kilometer domes over population centers. There was no way to reverse the damage done. We can't fly anymore so everything is in a very fast underground train system called "vac-trains". I suppose this may be where we are headed (although I'd rather love to see the vac-train system)

That one's the Edenist Universe or the MorningLightMountain universe?

Edenists.

MLM is the Commonwealth Saga, if I recall. First book “Pandora’s Star”

I’ve been in cat 1 and cat 2 storms. They’re awesome in their power for destruction. I’ve evacuated from a category 4 storm, which did a huge amount of damage in the city when it hit.

A category 5 storm is essentially going to destroy everything in its path already. What good would adding a 6th category do?

I lived in Florida for a long time, I can tell you that people don’t evacuate when it’s a cat 4 threatening to maybe become a cat 5. Having a category meaning “this is much worse than a 4” would be meaningful here. I see no reason to have an upper limit, it just artificially makes everything at and above the cat 5 threshold mean the same thing.

Also, Florida homes are built from cement, meant to survive storms like that. The building codes come from hurricane andrew, a particularly damaging cat 5.

> Having a category meaning “this is much worse than a 4” would be meaningful here.

But don't you think that cat 5 would become the new 4? That is: why do you think extending the scale will expand the range of warnings communicated, instead of smearing the existing range out over more values?

> don't you think that cat 5 would become the new 4?

The few who might be saved are worth it. We can’t keep optimising for saving idiots.

Florida gonna Florida. I grew up and still live in a hurricane area. Went through a cat 5 as a kid - not going to do that again. But, cat 2/3 or less I'm not going anywhere. Last time we took a direct cat 2, we didn't even lose power. Like you said, FL and really most of the southeast coast learned from Andrew. Simple changes like roof ties and more expensive ones like cement plank siding make a pretty significant difference [1].

TBH, my main concern in a storm is water. My house is ~12' off the ground and given its location, if there's water in the house we're basically in an end of days, biblical level storm.

[1] https://www.usglassmag.com/30-years-later-hurricane-andrew-r...

Not just cement, all new construction now requires impact windows and doors that can withstand a Cat 5 by default.

For Floridians, Cat 5 is scary but not that scary, Florida's one crazy state with sturdy buildings and only very select areas get leveled in major storms. There definitely needs to be a better way of rating hurricanes, for strength AND area of damage.

Hurricanes are extremely area focused, and they lose power FAST. It can miss you at the last second and not even knock a shingle off your roof, while leveling a trailer park 50 miles south of you.

Literally the only hurricane that made landfall in Florida as a Category 5 after Andrew was Michael in 2018, so most Floridians haven't experienced a Category 5 hurricane in decades (if ever). (Irma and Ian were downgraded before making landfall in the US.)

Michael did confirm that the new building codes were effective -- structures built prior to 2002 suffered much worse damage. From an early reconnaissance report [0]: "However, roof cover and wall cladding damage was still commonly observed even in newer structures. Failures were frequently observed in both engineered and non-engineered buildings."

Michael also highlighted that no matter how much you strengthen the building code, that means nothing for old buildings that haven't been updated, or for infrastructure (downed power lines and transmission towers, washed out roads and bridges, etc).

Would a Category 5 hurricane be more damaging if it struck Manhattan rather than Miami? Absolutely. IMO that's a consequence of climate change we should be worrying more about than peak storm strength -- more places (that don't necessarily have the same historical awareness) are going to be affected by stronger storms (and more frequently! 2020 saw two back-to-back Cat 4s make landfall in Nicaragua 15 miles and 2 weeks apart).

To say that Cat 5 isn't that scary in Florida is underestimating how incredibly rare these are, and overestimating the building code's coverage / efficacy.

[0] https://www.weather.gov/media/tae/events/20181010_Michael/St...

I recall the book 'Bannerless' by Carrie Vaughn, depicting a post-apocalyptic world that fell, not with a bang but with a whimper.

Erosion of public services, erosion of cities, millions then billions of refugees, starvation and disease, collapse of order.

This is the scenario we should be anticipating.

How much hardening is required to not be destroyed.

"multiple storms have already spilled over into the hypothetical category 6"

If they do go this route, I'd like it if they future-proofed it and include categories 6-10. Seems inevitable we're gonna see the first category 7 in the next 5-10 years.

Confusingly, the paper[0] cited by this article seems undecided on this front. Figure 1A of the paper puts Hurricane Patricia (2015) into hypothetical category 7, but the "current and proposed categories" in Table 1 stops at declaring category 6 wind speed > 86 m/s (or 192mph, 167 knots, 309 km/h), and category 7 doesn't make an appearance elsewhere in the paper.

I was really hoping to find an authoritative listing of the strongest storms, but it is missing in both the linked article and the underlying paper. The paper itself uses data from International Best Track Archive for Climate Stewardship, which has a confusing website. As a non-expert, the website's top windspeed[1] category lists the following storms with maximum wind speeds of >167 knots (category 6 in the proposed scheme):

    213kt - 1958 IDA
    194kt - 1958 GRACE, 1959 JOAN, 1959 DINAH, 1961 NANCY, 1964 SALLY
    185kt - 2015 PATRICIA
    184kt - 1961 VIOLET
    180kt - 1955 RUTH
    178kt - 1955 JANET,
    174kt - 1951 MARGE, 1953 NINA, 1956 WANDA, 1957 VIRGINIA, 1957 HESTER, 1957 KIT, 1957 LOLA, 1959 VERA, 1959 CHARLOTTE, 1966 KIT
    170kt - 1964 OPAL, 2013 HAIYAN, 2016 MERANTI, 2020 GONI, 2021 SURIGAE

I don't see any explanation for why there were so many fantastically powerful storms in the 1950s-60s. Perhaps the older data is of dubious quality?

[0] https://www.pnas.org/doi/full/10.1073/pnas.2308901121#t01

[1] https://ncics.org/ibtracs/index.php?name=browse-wind#210

Wikipedia gives Typhoon Ida (not to be confused with various hurricanes named Ida) a wind speed of "only" 175 knots (325 kph; 202 mph) which accounts for the largest outlier in the list.

https://en.wikipedia.org/wiki/Typhoon_Ida_(1958)

Confusingly, that wikipedia page cites the same IBTrACS system that I referred to, and in that page[0] the max intensity is listed at 213 knots. The data shows that the 213 knot speed was seen for measurements across twelve hours on 1958-09-24.

[0] https://ncics.org/ibtracs/index.php?name=v04r00-1958263N1314...

You are looking at the data for the CMA (China Meteorological Agency). The official data center for the Western Pacific according to the World Meteorological Agency is the Japan Meteorological Agency (JMA/Tokyo), but the IBTrACS dataset does not have wind speeds from them for 1958.

The Wikipedia article is sourcing data from the JTWC (Joint Typhoon Warning Center), the US wind column for 1-minute sustained wind speeds. In general, the Wikipedia convention is to include wind speed data from the JMA and JTWC when available.

There is some research regarding an increase in Saharan dust storms that retards hurricane development in the Eastern Atlantic. Apparently this is still trending upwards and has resulted in fewer hurricanes forming over the last few decades.

The scale is somewhat arbitrary (plot the points) but category 7 would start somewhere around 225MPH. Highest ever recorded is 215MPH, so category 7 is worth having in reserve.

Ida/Kanogawa was 245 mph/213 knot peak.

https://ncics.org/ibtracs/index.php?name=v04r00-1958263N1314...

Saffir–Simpson is based on sustained, not peak.

Set Category 10 at the speed of light, then work backwards...

Well that's easy. The meteorologists can remember that category number = 10 v' / c, where v' is the maximum median windspeed over a one hundred acre convex region, and all anyone else needs to know is that every storm is cat 0.

Agree, need to do this properly. What's a fair cap in our solar system?

"Neptune’s winds are the fastest in the solar system, reaching 1,600 miles per hour!"

What category is that?

https://scijinks.gov/planetary-weather/#:~:text=Neptune%27s%....

I would guess that atmospheric pressure is going to matter a lot for the expected "damage", so it would not make sense in places where it's wildly different ?

Why should we "create" categories. There should be an algorithm for determining level. Input 1000 miles an hour, you get a category.

Earthquakes don't have an upper limit. It's just a function of energy.

Earthquakes are sort of naturally limited though. A 9.0 is going to be catastrophic no matter what, and while I’m not saying a 10 couldn’t happen it would probably be something like once in a billion year event.

10.0 is firmly in "if it happens nobody's gonna be around to care what it's designated" territory I think. There's a practical point at which the death tolls are going to be sufficiently high that the number probably shouldn't matter.

Though in tornadoes there definitely are EF-4 designated twisters that are hotly contested online as being truly EF-5; often that's down to where damage occurs in the lifetime of a tornado though and it being difficult to prove windspeeds when a system is moving through, e.g.: trailer park vs an industrial park.

I don't think it's quite as cut and dried as that. A 9.5 hit Chile about 60 years ago, and about 95% of the most directly hit town survived. Which is not to minimize it - there were thousands of fatalities - but it was human scale tragedy, not apocalypse.

An estimate of the upper limit of an earthquake is approximately 10. It's a function of max rock strength.

It’s actually a function of energy released. The earthquake can get bigger if the fault slip is larger. A magnitude 12 quake is technically possible but requires an entire hemisphere to slip 500 meters. There’s a really interesting paper that takes the moment magnitude scale to its logical extremes.

PDF warning: https://www.fujipress.jp/main/wp-content/themes/Fujipress/pd...

Fair enough - something like rock strength and rupture length. Good paper. Thank you

I seem to recall something about the asteroid that killed the dinosaurs producing a magnitude 11.

I wonder what the collision that produced the moon rated?

Well, as long as they are only doing those in papers!

With regard to hurricanes, we are an active participant in creating the level of need for new terminology.

I seem to recall a video (perhaps KurzGesagt) that a magnitude 25 earthquake would overcome the binding energy of Earth - the planet would be in separate pieces. That definitely is an upper limit: when the "earth" in earthquake literally cannot take more.

Not necessarily because there may not be any difference between a wind speed of 350mph and 400mph wind in term of destructive power. Both may simply be able to strip the land bare and deliver the everything above it many miles away as well as temporarily moving parts of the sea miles inland.

By the time storms of 7+ come that level become commonplace, I doubt there will be people track and name them.

While that is probably most sensible, it doesn't seem like a lot of fun. Instead, I recommend we call a new global conference, every few years, to discuss the addition of each individual natural number to the Saffir-Simpson scale.

That does sound fun! Is the idea to progress sequentially? or do we consider the proposal of 13 before 7 if there is enough support to do so?

So my question would be, if the paper is logically sound then we are looking at a mechanism where the energy boost from increasing ocean temperatures is only applicable to the storms of cat 5. Why? Because we have data that show the yearly frequency of named tropical cyclones. The chart of these fequencies from 1980~2022 which I link below, indicates no discernable trend. This means that the postulated increase in storm intensity is somehow not promoting otherwise 'would-be' tropical storms into the cyclone categories. Consider the energy distribution over the 5 categories. So this leaves us with, if the logic of the paper is verified, a situation where only the kurtosis of that distribution is affected by ocean temperature -- and not any other statistial parameters. So this should be a future topic for study, why only the higher energy storms are enhanced and not the lower energy ones. In other words why is the kurtosis of this distribution enhanced by increasing ocean temperature? link: https://www.statista.com/statistics/1269915/number-named-sto...

It's nothing new to talk about, but rating a hurricane's destructive force on windspeed alone is sub-optimal.

On the other side, one-dimensional labels for a storm help convey the severity of it quickly and unambiguously.

Hurricanes have three components IIRC (as someone who lived on the coast a long time): Storm surge flooding, rain flooding, and wind.

Hurricane Ike was a cat2 in 2008, which did significant damage to the Houston coast because of its large storm surge.

Harvey in 2017 was damaging due to its consistent rain over the area as it stalled. Tropical storm Allison in 2001 was similar.

One may argue that wind causes the most acute damage as well as the fastest "change in status" of the three: High winds can topple a tree to block a road instantly, or rip the roof from a house in a flash, or knock down powerlines taking out a neighborhood.

While I'm not against a cat 6 or higher rating existing, for the sake of human communication "cat 5" means "get the hell out of there" already.

> Storm surge flooding, rain flooding, and wind

I use wind and the speed of the storm directionally as my mental model when thinking about hurricanes. Rain/surge flooding are results of how long the system is over an area.

That said if a storm is a 3+ I’ll leave - driving 3-4 hours is way more enjoyable than trying to sleep with no AC

> Hurricane Ike was a cat2 in 2008, which did significant damage to the Houston coast because of its large storm surge.

> Harvey in 2017 was damaging due to its consistent rain over the area as it stalled.

The outsider impression that I took away was that a major reason why Houston got so rekt by a mere Cat 2 hurricane was in large part driven by property developers building communities in low lying areas that the Army Corp of Engineers had designated as "emergency spillways"[1][2]...the Army knew about the risk, the city turned a blind eye, and the devil in the details weren't disclosed to homebuyers.

Perhaps there's more to the story?

> While I'm not against a cat 6 or higher rating existing, for the sake of human communication "cat 5" means "get the hell out of there" already.

I agree, but skipping town isn't always an option even if you wanted to; experienced two such events[3][4] on Guam as a kid.

[1] https://www.nytimes.com/interactive/2018/03/22/us/houston-ha...

[2] https://www.houstonchronicle.com/projects/2021/how-houston-f...

[3] https://en.wikipedia.org/wiki/Typhoon_Omar

[4] https://en.wikipedia.org/wiki/Typhoon_Paka

On the first point, you're correct about Harvey. Several neighborhoods were built in the basin of a flood plain. And lesser examples of such poor planning and drainage are all over Houston. But sometimes it really is storms that stall over the city dropping rain for three days.

To the second point, yeah... My family tried to evac Rita (2005) and got 5 miles in three hours. Turned around, and the storm missed us.

Three years later, my parents stayed for "cat 2" Ike and were trapped in the attic for 12 hours because Galveston Bay had come five feet up our house.

Any rating system is going to fail to be actionable until two things happen. 1, structures need to be rated by the level of wind they're able to withstand, and 2, geographic regions need to be categorized by their likelihood of flooding.

As it stands, as a person, you have no way of knowing if you have a cat X capable roof, nor do you know if you're in an area that is likely to flood, or how likely that area is to flood. Until you have a concrete rating system for those things, you'll have more people thinking that "We can just hunker down" when a cat X is barreling down on them than you want.

That sounds like a big bite to take, but, realistically, you can more or less tag existing houses based on when they were built (ie under which revision of the building code were they built) and then use USGS data to determine flood risk. Then, you categorize all of the above by storm, ie, live in a cat 3 area with a cat 4 house? Evacuate if you have a cat 3 storm because it's going to flood. That will also inform localities as to which areas are going to need to be evacuated first, along with which areas are going to need more emergency assistance post-storm so resources can be allocated more efficiently.

We're already kinda sorta accounting for this at the local level, but, codifying the practice allows it to scale and improve over time.

All models are wrong, but some are useful. Hurricane ratings have proven to be very useful.

The problem with this is that wind speed alone is not a good indicator of how destructive a storm can be. Storm surge, mud slides, etc., contribute and can be deadly even in a category 1 or 2 storm. If the scale is to be updated, it would be beneficial to include other factors in addition to wind speed.

Wind speed is measurable before landfall, many other destructive indicators are only so after the destruction is done.

The enhanced fujita scale for tornadoes takes into account an assessment of damage after the fact to make a guess of the wind speeds that were produced. An after-the-fact assessment of hurricanes could be useful in creating a categorization that better communicates risk to persons than just windspeed.

Maybe, but the Fujita scale can greatly under report strength, because the higher grades need to be justified by damage to modern, well built structures. There are tons of tornadoes that meteorologists are sure are at least EF-4 based on Doppler and video, but are rated at EF-1 or EF-2 because they didn’t hit anything but cornfields and sheds.

Isn’t that the system working as-designed? We don’t really need to blast the alarm for a few stalks getting bent out of shape.

It can lead to a false sense of security... maybe if it turns east instead of north east it barrels into downtown Omaha.

In the most extreme case a small tornado in a larger storm that hits no man-built structures may go totally unrecorded.

Essentially if you assess tornado risk as something like (frequency * severity) / area, this will under assess risk to a previously developed area that is now being developed. Before there was nothing to hit. Now there is.

I think that's also the challenge of using the same categories/windspeeds of the Saffir-Simpson scale when applying it to a place like Jamaica vs Houston. Both places may face a cat4 hurricane and see very different levels of damage entirely due to the difference in infrastructure.

Its a matter of informing people how to use the scales - we have temperature and wind chill but people still need to know that -40° will hit the Midwest much differently than -40° would hit Texas.

Classic example: https://en.wikipedia.org/wiki/2013_El_Reno_tornado

This had wind speed measured by radar, but ultimately didn't hit any substantial structures, so they couldn't justify anything above EF3. Tornadoes are only rated based on the damage they do to damage indicators, the wind speeds are just best guesses.

A well placed tree can make any storm deadly, it's perfectly fine to separate the size of the storm from the potential impact. You need to draw a line somewhere. Drawing it at the part you can measure/predict is pragmatic and sensible.

I disagree. Wind causes a different type of damage than mud slides, storm surges, etc.

For instance, if you live at high altitudes, you can ignore storm surge when preparing your house.

This might be true but paradoxically, there hasn’t been an observed frequency or intensity of Florida hurricanes in last 100 years [1].

Florida is worth looking at because they were industrialized and have had relatively robust meteorological record for the entire period.

I do wonder why as it seems like common sense that heating air and water temps (which have happened) would cause more evaporation and potential for water and wind storms.

[1] https://www.gfdl.noaa.gov/global-warming-and-hurricanes/

For futureproofing, we should extend the scale to cover hypercanes [1], which (according to Wikipedia):

- require ocean temperatures of 120 °F (50 °C)

- have sustained winds of 500 mph (800 km/h)

- have barometric pressures in their centers sufficiently low enough to cause altitude sickness

- may persist for several weeks due to above low pressure

- may be as large as North America or as small as 15 mi (25 km) — Wikipedia has an unhelpful caption about the size of the "average hypercane" (!)

- extend into the upper stratosphere, unlike today's hurricanes (lower stratosphere)

- due to above height, may sufficiently degrade the ozone layer with water vapor to the point of causing (an additional) hazard to planetary life

As of today, both a hypercane and a regular, run-of-the-mill catastrophic hurricane would be rated a Category 5. But I suppose hurricane categorization and nomenclature would be the least of NOAA's problems in such an event.

[1] https://en.wikipedia.org/wiki/Hypercane

> But I suppose hurricane categorization and nomenclature would be the least of NOAA's problems in such an event.

This is implausible to me. Just to be safe, we should get the naming done up front.

I'm skeptical about one of the opening sentences in the article: "category 5 underestimates actual risk".

Category 5 cyclones/hurricanes are already assumed to essentially destroy everything in their path. This will still be true regardless of how strong the winds get.

Having experienced several lower category cyclones, there really isn't a lot to do except 1/ evacuate if you've got time and a place to go or 2/ bunker down and pray. It's just luck that I've not experienced a direct hit from a higher category storm.

I like how this is basically scientists arguing about tier lists. The stats tell the story but people just love to rank things.

Another Emergency to take care of. This is the reason why TV/movies lost mojo since a decade ago, its a better entertainment to wait for the next emergency (and read about it in the media) than waiting for the next blockbuster.

This is exactly the premise of Bruce Sterling’s novel “Heavy Weather”.

Classic spinal tap. “These go to eleven.”

There is already lots of discussion about science communication in this thread, but I think what would also be extremely important is good communication after the scale has changed.

Should there be a decision to extend the scale, the fact that there was a change should be communicated as widely as possible: Make it an item in the evening news, put a footnote in every article that uses the term "category 6 hurricane" for a few months, etc. Explain exactly when the scale was changed, who made the decision and on what grounds.

Because if not, this will be an open flank for climate denialists: I think the "natural" tendency of most media outlets would be to just quote press releases or forecasts verbatim and use the new term as if it had always been there. To uninformed viewers, this would give the impression that either the scale always went to 6 and they just somehow never noticed or that the scale was open-ended and we're now getting the first cat6 hurricanes because of climate change.

Both assumptions are obviously wrong, and so a climate denialist will gleefully pull out their "research" that the scale has been changed as evidence of manipulation and conspiracy. I think this is something that should strongly be avoided.

Next thing you know they'll be trying to make category 7 hurricanes official

I had previously heard that category 5 storms were originally thought to be impossible, and only became possible due to global warming adding more energy into the atmosphere. The article however states that category 6 was technically possible as far back as 1979. Have these category 5, 6 and maybe higher always been possible, but just more improbable?

There were 19th century storms that were clearly 5s, at least. Whoever told you that didn’t know that the hell they were talking about, to put it mildly.

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