Do We Need a Category 6 for Hurricanes?

[Randy Zipser]

Here's an article from the Gizmodo newsletter on September 29th that debates this issue:

Do We Really Need a Category 6 for Hurricanes?

 

[JamesCaruso]

This article is indicative of why some of us refer to a “media narrative” about climate change. The subtitle begins, “As climate change leads to more destructive hurricanes…” Climate change may be real, but to my knowledge there is absolutely no basis for concluding that it leads to “more destructive hurricanes.” It’s easy to see why people get suspicious that an agenda is being pushed - it’s like if you just keep repeating a supposition often enough, everyone will just accept it.

 

[John Farley]

I think it is pretty well-accepted science that extreme heavy rainfall and rapid intensification in hurricanes are becoming more common. Both of which can be associated with higher ocean temperatures and the capacity of warmer air to hold more moisture. And extreme heavy rainfall and rapid intensification do make hurricanes more destructive. I do not understand why people want to refer to such science as an "agenda" or "narrative." Now before people jump on me, I agree that not all changes associated with climate change are bad. For example, tropical cyclone frequency does not seem to be increasing overall. But since the vast majority of climate scientists agree that climate change is real and that human factors are contributing to it, I do not see why people keep referring to it as an agenda or narrative. "Scientific near-consensus" would be more accurate terminology. If anything, terms like "agenda" and "narrative" are better applied to those who deny climate change, since they are going against the large majority of scientists.

 

[Randy Zipser]

This article is indicative of why some of us refer to a “media narrative” about climate change. The subtitle begins, “As climate change leads to more destructive hurricanes…” Climate change may be real, but to my knowledge there is absolutely no basis for concluding that it leads to “more destructive hurricanes.” It’s easy to see why people get suspicious that an agenda is being pushed - it’s like if you just keep repeating a supposition often enough, everyone will just accept it.

All valid points, James. I don't think the intent with this article is so much to "push" a climate-change/global-warming point of view, as to offer some quasi-scientific explanation (that the general public will readily accept) upon which to base a reason why the question should be even posed in the first place.

There's more to this question than just "media soundbites;" there's actually some real science behind this question. On a global scale, oceanic circulations and atmospheric circulations work on totally independent spatial and time scales. However, they are not entirely "closed" systems because they share an interface where both latent heat (and, thus, potential energy) are continuously being exchanged. The physics of thermodynamic entropy alone may (or may not) explain whether adding more sensible heat or potential energy into the oceans will translate directly into some observable, measurable (more orderly or less orderly?) metric with atmospheric events such as hurricanes, thunderstorms, or tornadoes. It's very much an open question for further long-term scientific study...

The discussions between the various "experts" in this article are interesting because most, if not all, these people are "qualified" to be a part of this discussion because of ties to academia or professional practice. They are not political or journalistic types looking to advance a particular narrative to suit some disinformation or "conspiracy theory" agenda like so many on the Internet and social-media are nowadays.

We must keep an open mind to all viewpoints, and follow where factual science (and the laws of Newtonian physics) take us.

 

[Randy Zipser]

I think it is pretty well-accepted science that extreme heavy rainfall and rapid intensification in hurricanes are becoming more common. Both of which can be associated with higher ocean temperatures and the capacity of warmer air to hold more moisture. And extreme heavy rainfall and rapid intensification do make hurricanes more destructive. I do not understand why people want to refer to such science as an "agenda" or "narrative." Now before people jump on me, I agree that not all changes associated with climate change are bad. For example, tropical cyclone frequency does not seem to be increasing overall. But since the vast majority of climate scientists agree that climate change is real and that human factors are contributing to it, I do not see why people keep referring to it as an agenda or narrative. "Scientific near-consensus" would be more accurate terminology. If anything, terms like "agenda" and "narrative" are better applied to those who deny climate change, since they are going against the large majority of scientists.

I absolutely, totally agree, John. Please see my reply to James above!

 

[Boris Konon]

This article is indicative of why some of us refer to a “media narrative” about climate change. The subtitle begins, “As climate change leads to more destructive hurricanes…” Climate change may be real, but to my knowledge there is absolutely no basis for concluding that it leads to “more destructive hurricanes.” It’s easy to see why people get suspicious that an agenda is being pushed - it’s like if you just keep repeating a supposition often enough, everyone will just accept it.

An article that asks a question in its headline or subtitle, this is a common tactic in the MSM and reeks of the loaded question logical fallacy. Also, asking questions I have found is often subtly abused as giving carte blanche to ask *anything*, no matter how ridiculous or off-base it is. It is merely a tool to stir the pot and get clicks/likes.

The subtitle up-front is also a poisoning the well logical fallacy, immediately introducing bias and a contested topic, thus contaminates the reader's perception from the start.

More destructive hurricanes from warmer temps? How? If they are going by costs, that is patently false. Costs from hurricanes (and wx in general) are almost entirely due to more infrastructure and ppl everywhere all the time (esp. at the coast), inflation, wealth distribution, and other societal factors that have nothing to do w/ wx/climate. These details continue to get ignored in the mainstream narrative, treating ppl like they are stupid or ignorant. Costs would still continue to sprial out of control from wx events if the temps rose, stayed the same, or dropped. This is an uncontestable fact.

And the higher winds/more rain as a threat from warmer temps, it is not so simple. Construction that is subpar leads to more wind damage Poor land/water management and building on flood plains, that leads to more flood damage. The point is there are *many* variables that exist, and climate change is only one of them. Climate change is treated like it is *only* factor out there that causes harm/destruction, and we have to throw trillions of dollars at it to "fix" it. This is not a science-based approach, and suggests large-scale grift, corruption, and political agenda.

As an example, attached is a diagram showing how complex migration factors are in Senegal. Climate change is one of them, but among many others, and it is interconnected. Yet you get headlines blaming climate change only for mass migrations, famine, political unrest,, you name it. This is where the argument falls apart as to the net magnitude of climate change as a risk or factor.

 

[Boris Konon]

I think it is pretty well-accepted science that extreme heavy rainfall and rapid intensification in hurricanes are becoming more common. Both of which can be associated with higher ocean temperatures and the capacity of warmer air to hold more moisture. And extreme heavy rainfall and rapid intensification do make hurricanes more destructive. I do not understand why people want to refer to such science as an "agenda" or "narrative." Now before people jump on me, I agree that not all changes associated with climate change are bad. For example, tropical cyclone frequency does not seem to be increasing overall. But since the vast majority of climate scientists agree that climate change is real and that human factors are contributing to it, I do not see why people keep referring to it as an agenda or narrative. "Scientific near-consensus" would be more accurate terminology. If anything, terms like "agenda" and "narrative" are better applied to those who deny climate change, since they are going against the large majority of scientists.

"Scientific near-consensus" would be more accurate terminology. If anything, terms like "agenda" and "narrative" are better applied to those who deny climate change, since they are going against the large majority of scientists."

Consensus is not evidence. Just b/c many or the majority say something is true, does not mean it necessarily is. There are many examples of this throughout history.

Historically, the claim of consensus has been the first refuge of duplicity. It is a way to avoid debate by claiming that the matter is already settled. Consensus is invoked only in situations where the science is not solid enough. Nobody says the consensus of scientists agrees that E=mc2. Nobody says the consensus is that the Sun is 93M mi away. It wouldn’t occur to actual scientists to talk that way.

Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that one has results that are verifiable by reference to the real world. In science, consensus is irrelevant. What is relevant is reproducible results and empirical evidence. The greatest scientists in history are great precisely because they broke w/ the consensus. There is no such thing as consensus science. If it’s consensus, it isn’t science. If it’s science, it isn’t consensus.

 

[Randy Zipser]

Really great discussions all, guys!

When I originally posted this article, I was not intending it to lead to the excellent discussions above about the scientific/non-scientific merits of climate change/global warming as related to justifying a Category 6 classification for the Saffir-Simpson hurricane wind scale (SSHWS) presently in use. It is unfortunate that the article's author chose to start off with the remark about climate change which, as both James and Boris correctly point out, "taints" the author's motive from the outset...

But looking beyond that, I was hoping to stimulate some discussion about what the five "experts" cited in the article had to say about the question the title of the article asks. To summarize:

Jennifer Collins proposes a "TCSS" as a different way to classify tropical cyclone severity from the SSHWS;

Brian McNoldy says that partitioning the SSHWS into more or smaller increments would add no value and even cause more confusion when communicating with the public;

Liz Ritchie-Tyo suggests a multi-factor classification system that can communicate risks of various hazards;

Daniel Brown (who is a NHC Branch Chief) says that there are no "official" plans to change the SSHWS;

Mark Bourassa suggests that adding a new category to the SSHWS will not meaningfully change the public's response.

Taking all these points of view in aggregate, my takeaway (FWIW) is that adding a new category at the top of the SSHWS or coming up with a new classification system that also takes into account the potential for flooding rainfall and coastal storm surge may help in providing a little more detailed picture of the storm's behavior for post-scientific research and data details/recrord-keeping, but may not necessarily be practical or more useful at the time the number-one priority is to warn the public in the path of a potentially landfalling tropical cyclone, especially a major one (Cat 3+).

Are there any comments on that topic?

 

[John Farley]

A couple things. First, while what Boris says above is absolutely true, I do not think it supports the use of terms like "agenda" and "narrative," which have been used in a pretty one-sided way in the discussion of climate change. They seem at least equally applicable to those who deny climate change and/or human contributions to it. And while science is indeed based on evidence, not consensus, I think the term I suggested is at least as accurate as those, probably more so, because it is a near-consensus. At this point, the burden of evidence seems to be primarily on those who want to disprove that conclusion.

Second, to Randy's question, and to get the thread a bit back on track, it seems to me that a Category 6 would pointless when such a small percentage of storms even reach Category 5. Additionally, the Saffir-Simpson ratings are often considerably higher than any measured wind speeds. I know it is true in many cases that the speeds associated with the category do occur somewhere without measurement, but the regularity of big discrepancies suggests to me that in some cases the rating might be higher than the reality. And if even leaving that out, Category 5 storms are a relative rarity, what would be the point of adding a Category 6?

 

[Randy Zipser]

And if even leaving that out, Category 5 storms are a relative rarity, what would be the point of adding a Category 6?

If the hurricane classification scale took into account three variables (rainfall, surge, and wind) instead of just one (wind), would that change the overall potential range of the severity window, thus allowing for more categories? I agree that as far as tracking, advisories, and landfall warnings are concerned, simpler communication is better for public dissemination. The distinction might be more of an academic question than one that has any practical application. I agree: let well enough alone...if it ain't broke, don't fix it!

 

[John Farley]

I can see the argument for basing the categorization on rainfall and surge as well as wind, although when you add complexity you probably decrease accuracy at the forecast stage. But I think the question of what should go into the categorization is a different one from how many categories there should be. Even if Category 5 was a larger percentage of storms in some new categorization system, I would probably still stick with 5 categories because that is what people are used to and familiar with.

 

[Randy Zipser]

The distinction might be more of an academic question than one that has any practical application. I agree: let well enough alone...if it ain't broke, don't fix it!

Upon second thought, maybe I am being too quick to draw that conclusion. So, I went online and did some research, asking the questions: "Are more people killed by wind or water in a major hurricane?" Similarly, "Is more property damage done by wind or water in a major hurricane?"

The AI-generated results are as follows:

1. Studies show that approximately 86% of hurricane fatalities in the U.S. are due to water impacts, such as flooding and storm surge, while only 12% are caused by wind.

2. However, studies indicate that wind tends to cause more immediate structural loss, while water damage can be more extensive and persistent, affecting a larger area and leading to long-term issues (no percentage breakdown given).

These studies lead to two possible conclusions:

1. If both wind and water could be incorporated into a single tropical cyclone classification scale, would it make sense to expand the scale range, thus allowing more than five category levels, as is now the case with the Saffir-Simpson scale? Or,

2. Would it make sense for the public to have two separate classification scales: one for wind and one for water risk? To cause less confusion, as a matter of routine practice, all public advisories (TS or hurricane watches issued) would use only the S-S wind scale. Then, only when hurricane warnings are issued for specific areas of coastline (where surge is expected), residents of those areas would be provided an additional water-risk assessment (if such could be put into a scale), the idea being that perhaps with this additional piece of information, property-owners on surge-prone beaches or barrier islands who are in imminent danger might be "scared' into evacuating safely when otherwise they would not have using the S-S scale only. Would that practice save more lives going forward?

Any thoughts?

 

[Randy Zipser]

...residents of those areas would be provided an additional water-risk assessment (if such could be put into a scale)...

The old brain cells do not work so well in the wee hours of the morning when I wrote that statement. But upon further reflection, it seems that it would not be impossible to devise a "water risk assessment scale" (WRAS) for tropical cyclones (TC) or tsunamis, for that matter.

The two main factors that would affect water-damage risk would be:

1. Amount of population in the direct path of anticipated TC landfall: larger the population, the higher the risk factor; and

2. Physical characteristics of the underlying seafloor slope in the path of the land-falling TC: a shallow coastline slope (e.g., Gulf continental shelf off the west coast of FL) produces a greater surge than a steeper slope (e.g., Gulf Stream current along SE FL Atlantic coastline), so the waves push the water inland faster than it can drain off due to very flat terrain. The physical mechanics of this process are shown in the attachment below.

Both of these variables (at least for all U.S. coastlines) should already be mapped, so these data would be readily available in advance of a TC to be applied in each specific event, as necessary.

One could also make the argument that the Saffir-Simpson (SSHWS) scale now in use is getting a bit antiquated, having been first introduced in 1971, considering the computer-modeling advances and database storage archives for TCs that exist nowadays.