Chris Mooney: Hurricane Dean Is the Ninth Most Intense Atlantic Hurricane Ever Measured

Chris Mooney writes:

Hurricane Dean: 1 Of 10 Most Intense Atlantic Hurricanes Ever Measured: Early this morning Hurricane Dean... slammed the Yucatan Peninsula around Chetumal as a Category 5 hurricane with winds upwards of 165 miles per hour and a minimum central pressure of 906 millibars.... Its pressure was the ninth lowest ever measured in the Atlantic, and the third lowest at landfall. Indeed, there hasn’t been a full Category 5 landfall in our part of the world since 1992’s Hurricane Andrew. Dean was in all respects a terrifying storm, and we can only hope that the damage will somehow be less than expected as it tears across the peninsula and then, after crossing the Bay of Campeche, moves on to a presumed second Mexican landfall.

No one storm says anything about climate change; but... let’s consider the storm from a climate perspective, bearing in mind the scientific expectation that global warming ought to intensify the average hurricane (by how much remains hotly disputed). How does Dean fit into that ongoing scientific argument? Well, first of all, Dean now takes its rank among the top ten most intense Atlantic hurricanes. If you look at that list you’ll see that six of the strongest (Wilma, Rita, Katrina, Mitch, Dean, and Ivan) have been in the past ten years. That’s not the kind of statistic that’s easy to overlook. According to these data we are getting more super-strong storms in the Atlantic basin than we ever have before.

To be sure, there’s a counterargument here: Data wasn’t as good on hurricane intensity in previous eras as it is today, when our measuring equipment is better than ever. Stronger storms may well have existed in the past, but we were simply incapable of detecting their true strength.

This is a serious objection, although it’s hard to know precisely how serious. Nevertheless, the fact remains that if you look at the official records, Dean now fits in to a staggering hurricane decade. That’s highly suggestive, if not definitive. And this staggering decade has occurred in part because of anomalously warm ocean temperatures in the hurricane-prone regions. Many scientists question whether you can explain these warm anomalies without invoking global warming as at least part of the cause. So once again, even though Dean was not “caused” by global warming, when considered in its Atlantic context the storm is certainly consistent with the argument that there’s something going on out there that’s new — and more than a little scary...

Comments

[rjh]

Mr Mooney is being more than a little disingenuous. Prior to availability of satellite information only about 1/2 of all Atlantic hurricanes were detected. The entire eastern Pacific hurricane zone was unknown before satellites. Prior to 1995 there was not agreement on how to measure hurricane intensity, and the older hurricane ratings have not be re-scaled to the current definition. There is no world-wide trend of increases in hurricane intensity, just a North Atlantic increase, and the expert (Dr. Gray) in predicting North Atlantic hurricanes argues that other causes explain the North Atlantic increase.

There is clear evidence for multi-decadal cycles of hurricane activity, so it is misleading to look at the one recent decade and suggest that it represents a climate process and is not part of the multi-decadal cycles. If this were a worldwide trend it would be different. The evidence is that the multi-decadal cycles are not globally synchronized, so a global trend could more easily be argued to be independent of the cyclic activity. But this trend is only visible in the North Atlantic, and is consistent with the still poorly understood multi-decadal cycles in the North Atlantic.

There are other forms of evidence that do much more clearly indicate climate variations. Mis-representing events like this as an indication of climate variations does harm by associating emotional non-scientific arguments with the other much stronger scientific arguments for climate variations. It will lead to discrediting the scientific arguments when the cyclic behavior component is understood.

[Sebastian Holsclaw]

He is almost self-refuting: "Indeed, there hasn’t been a full Category 5 landfall in our part of the world since 1992’s Hurricane Andrew."

Most of the popular understanding of how intense hurricanes are comes from the low point of recorded hurricane intensity the 1970s and 1980s. If you could ask people from the 1930s and 1940s you'd see a different story.

[bigTom]

now rjh: I saw lots and lots of caveats in Chris's article. He merely says the trend is suggestive -and I think it is. The insurance industry seems to agree (although to them a secular change due to human influences, or a return of a multi-decadal cycle makes little difference). Like so many areas where the data is of poor quality, and other poorly understood (natural) variations may be at work there is no way to know for sure.

[rjh]

But bigtom: there is the difference between science and emotion. The usual scientific principle is to examine the theories with the most evidence, both looking to buttress them with more evidence and eliminate some with counter evidence. In this case we have data that supports the most likely theory of the multi-decadal atlantic oscillation (MAO) at work. It reinforces that theory. It could also fit a variety of other theories, but it does not indicate any problems with the multi-decadal theory. So it should be viewed as supporting the MAO, not as a climate effect.

Arguing a global climate change cause for a purely North Atlantic phenomenon with no supporting theory for why a global climate change should only affect the North Atlantic is just emotion. Taking the emotional path of claiming climate is unscientific. Unscientific politicians are nothing new. We have a large crew of them in power right now. But it is emotion, not science.

As for the insurers, they are basically very late and were severely damaged by government policy. One of the earliest analyses pointing toward the MAO was Hurd C Willet's 1955 report to the Insurance council, predicting that from 1960 to 1990 there would be low hurricane damage and from 1990 to 2020 there would be high hurricane damage. The understanding of the MAO is better now, but the original forecast was not bad. What is understood now is that the MAO is an erratic cycle. The El Nino cycle is another betterknown erratic cycle with a typical period of years rather than decades.

The major villain in the insurance arena is the US and coastal governments. From 1970 onward the meteorologists were warning that the coastal development policy was insanely stupid because the hurricanes were going to come back. It used to be (up until 1960s) that there were empty barrier islands that would routinely be destroyed by winter storms and hurricanes. They would completely eliminate and reshape the islands.

Now those empty islands are full of houses, condominiums, and commerce. Instead of relocating sand, hurricanes do billions of dollars in damage. This construction is only possible because of government flood insurance and development money to get access to the islands. Now that the hurricanes have returned the price will be phenomenally high.

For those who are interested in old history the hurricane re-analysis project page is at http://www.aoml.noaa.gov/hrd/data_sub/re_anal.html
So far it is up to the 1930's. Some of the presentation documents do a good job explaining all the difficulties and differences in the observation methods from the 1851 to present.

[rjh]

For those interested in the scientific view, the following papers may be of interest. Some are covered by AMS copyright which has given NOAA permission to make them available on the Internet. Further distribution and use is subject to the AMS policies.

The 2006 State of the Climate Report (36+ MB) http://www.aoml.noaa.gov/hrd/Landsea/belletal2007.pdf

The deadliest and strongest hurricanes 1851-present http://www.aoml.noaa.gov/hrd/Landsea/Blakeetal_noaamemoApr2007.pdf

Response to the paper arguing for climate cause of hurricane activity changes: http://www.aoml.noaa.gov/hrd/Landsea/reply_globwarm.pdf

There is a problem in that only a few of the scientific publications take the fairly generous attitude of the AMS regarding making scientific papers available to non-subscribers. This restricts the public access to real science, enabling the emotional appeals to gain undeserved credibility.

[dgl]

I saw Chris Mooney on CSPAN and he seemed a straight-up well-researched reporter type. From his comments there, I would say he knows the multi-decadal oscillation well, and reading the full article I think he appropriately caveats. I would not have bothered to read the article fully absent the CSPAN experience. A data point on the sociology of noOneKnowsDogInternet.

MAO can also be thought of like recessions and booms for portfolios of fluctuating stocks, and we know practitioners there use many, many, decades of information for their conclusion.

[Tim Worstall]

It's also true that the longer you measure a variable the more likely you are to get extremes.

[anne]

"It's also true that the longer you measure a variable the more likely you are to get extremes."

http://blog.sciam.com/index.php?p=208&more=1&c=1&tb=1&pb=1#more208

July 8, 2006

Wishful Thinking on Global Warming
By John Rennie

Keeping to the hardcore skeptic game plan of denial-in-depth, which you may recall goes like this:

(a) Global warming is not real.

(b) Even if it is real, it is entirely natural.

(c) Even if people are causing it, it is nothing to worry about.

(d) Okay, it is something to worry about, but there's nothing we can do about it (optional: anymore) except adapt. Economic growth and technology will eventually make it all okay.

-- Start at the top and work down only as necessary; whenever possible, find opportunities to jump higher up the list again and repeat.

[ -- Remember all along the way to blame liberal hysterics for ever calling attention to the problem. ]

[anne]

"It's also true that the longer you measure a variable the more likely you are to get extremes."

Yes; we have no bananas.

[anne]

"Mr Mooney is being more than a little disingenuous...."

"He is almost self-refuting...."

"It's also true that the longer you measure a variable the more likely you are to get extremes."

Yes; we have no bananas. Global warming?

[Alex Tolley]

TW says this: "It's also true that the longer you measure a variable the more likely you are to get extremes."

Anne: You respond with yet another rant. Your attempts at shutting down conversations is getting very tedious.

[bigTom]

rjh:
I will give you a bit, it did seem that Chris was reacting a bit to Dean. The apparent fact that cat 4/5 seems to becoming pretty common. I suspect your first read was expecting to see "climate-change caused this", and the caveats in the article didn't make much of an impression on you. I read it as as science writer explaining the uncertainties to a lay audience (slate readers), and thought he did a good job of covering the uncertainties. He probably should have left out the last sentence.

Even if we had non-controversial data on the last MAO peak, it probably wouldn't settle much (unless it was seen to be at least as strong as the current one) since such phenomena are likley to be somewhat irregular, with variable peak intensities. Nevertheless we know the fuel for tropical cyclones is warm water, which is increasing due to climate change. Not pinned down are other effects such as atmospheric shear, and storm initiation, so I suspect theory can provide only a little predictive capability on this subject.

[anne]

http://www.nytimes.com/2006/01/10/science/10conv.html?ex=1294549200&en=d2fde8dc2e248fb4&ei=5090&partner=rssuserland&emc=rss

January 10, 2006

With Findings on Storms, Centrist Recasts Warming Debate
By CLAUDIA DREIFUS

For decades, Kerry Emanuel, the meteorologist and hurricane specialist from the Massachusetts Institute of Technology, was known as a cautious centrist on questions of global warming and hurricane ferocity.

Professor Emanuel asserted often that no firm link had been established between warming and the intensity and frequency of hurricanes.

But in August, two weeks before Hurricane Katrina struck the Gulf Coast, Professor Emanuel wrote in the journal Nature that he had discovered statistical evidence that hurricanes were indeed affected by global warming. He linked the increased intensity of storms to the heating of the oceans.

"His paper has had a fantastic impact on the policy debate," said Stephen Schneider, a climatologist at Stanford. "Emanuel's this conservative, apolitical guy, and he's saying, 'Global warming is real.' "

On a recent visit to New York, Professor Emanuel, who is 50, said, "It's been quite a ride since the Nature article." He added, "But it's a really bad thing for a scientist to have an immovable, intractable position."

Q. Let's go back to late August. What were your feelings as you watched television and saw Hurricane Katrina heading toward New Orleans?

A. I'll go back to a few days before that. As Katrina was making up off the coast of Florida, it was already an interesting storm. Though she was weak, the prediction was she was going to hit Florida.

But when Katrina came off the west coast of Florida, there were new predictions taking it into the central gulf and then up toward New Orleans, and I became concerned.

Many people in my profession had been worried about New Orleans for a very long time. And we had always envisioned these worst-case scenarios, and this was beginning to look like one of those. And so I plotted out the position of the "loop current," which is this warm current of water in the Gulf of Mexico, and the forecast had the hurricane going right up the axis of this loop current.

I remember looking at that, and alarms went off. I had this terrible feeling of dread, which deepened when the hurricane was elevated to a Category 5. We all knew that the pumps that kept New Orleans dry wouldn't be able to handle more than about a Category 3....

[anne]

"It's also true that the longer you measure a variable the more likely you are to get extremes."

Chris Mooney has been documenting the anti-science and anti-scientist and anti-global warming stance of George Bush's administration. Here where we have Mooney making some interesting observations about hussicane Dean, at once we find Mooney being attacked but those who really are after attacking the ever growing evidence of global warming.

Imagine my surprise; global warming skeptics are getting ever so tedious.

[anne]

http://www.nytimes.com/2004/09/30/science/30hurricane.html?ex=1254283200&en=d11529bf8d60b813&ei=5090&partner=rssuserland

September 30, 2004

Global Warming Is Expected to Raise Hurricane Intensity
By ANDREW C. REVKIN

Global warming is likely to produce a significant increase in the intensity and rainfall of hurricanes in coming decades, according to the most comprehensive computer analysis done so far.

By the 2080's, seas warmed by rising atmospheric concentrations of heat-trapping greenhouse gases could cause a typical hurricane to intensify about an extra half step on the five-step scale of destructive power, says the study, done on supercomputers at the Commerce Department's Geophysical Fluid Dynamics Laboratory in Princeton, N.J. And rainfall up to 60 miles from the core would be nearly 20 percent more intense.

Other computer modeling efforts have also predicted that hurricanes will grow stronger and wetter as a result of global warming. But this study is particularly significant, independent experts said, because it used half a dozen computer simulations of global climate, devised by separate groups at institutions around the world. The long-term trends it identifies are independent of the normal lulls and surges in hurricane activity that have been on display in recent decades.

The study was published online on Tuesday by The Journal of Climate and can be found at www.gfdl.noaa.gov/reference/bibliography/2004/tk0401.pdf.

The new study of hurricanes and warming "is by far and away the most comprehensive effort" to assess the question using powerful computer simulations, said Dr. Kerry A. Emanuel, a hurricane expert at the Massachusetts Institute of Technology who has seen the paper but did not work on it. About the link between the warming of tropical oceans and storm intensity, he said, "This clinches the issue." ...

[walkingtheline]

I don't think Anne is ranting at all, Alex. Global warming theories predict more intense hurricane activity. We are observing such activity.

Occam's razor suggests that skeptics like yourself should come up with better arguments than, "we can't explain it, but it's probably just an erratic climate." My personal belief is that we are just entering a climatic Kondratieff upturn, but I won't be publishing my case without further evidence.

[Alex Tolley]

From RealClimate.com

18 June 2007
Storm World: A Review
Filed under:

* Reviews
* Hurricanes
* Climate Science

— mike @ 9:46 AM

If you are a RealClimate regular, you are undoubtedly aware of our ongoing interest in the developments in the scientific understanding of potential hurricane-climate change linkages. This is an area of the science where a substantial body of significant new research has emerged even since RealClimate's inception in late 2004. The scientific research in this area, and the media frenzy and political theatrics that have inescapably followed it, are thoughtfully placed in a broader historical context in a fascinating new book by Chris Mooney entitled Storm World: Hurricanes, Politics, and the Battle over Global Warming. Anyone who is at all interested in the scientific history that has led to our current understanding of Hurricanes and their potential linkages with climate change, will find this book a page turner. The book is a nice complement to Kerry Emanuel's recent book Divine Wind: The History and Science of Hurricanes (which too is so readable that it lies on our coffee table). Mooney in a sense picks up where Emanuel's left off. Like Emanuel, he explores the history of the science. But he uses this historical context, and his studies of the personalities of key actors, to explore how the current scientific debate can be traced back to a rift that has emerged over many decades between distinct communities of atmospheric scientists.

Those looking for a polemic (the title of Mooney's previous book, after all, was "The Republican War on Science") will be disapointed. Mooney has clearly matured as a writer, and this latest book constitutes his best effort to date. He delivers a thoughtful, non-partisan, and scientifically and historically accurate review of the emergent science exploring the potential influence of climate change on hurricanes.

If you've followed the scientific debate on global warming and hurricanes, you will recognize many of the characters in Mooney's tale (yours truly even gets mentioned a few times :) ). You will also not be surprised to find that William Gray and Kerry Emanuel are the two most prominently featured scientists. In part of course, because they neatly symbolize the two opposing camps in the current debate: contrast for example Emanuel's work demonstrating a linkage between increasing hurricane intensity and global warming with Gray's denial of any such link. However, Mooney also traces their respective work back to two different historical schools of thought in the atmospheric science community. On one side are the data-driven empiricists, such as Redfield, Loomis,and Riehl and on the other side the theorists such as Espy, Ferrel and Charney. Gray naturally follows in the tradition of the first group (his Ph.D adviser was Riehl who is sometimes credited as the father of the field of tropical meteorology). Emanuel, a student of Charney, follows in the tradition of the great theorists in atmospheric science. Of course its not quite that simple (and Mooney acknowledges as much). Though Emanuel may perhaps be best known for his theoretical investigations of Hurricane potential intensity, he has also done considerable work analyzing observations. And while best known for his work deducing from observations the parameters governing hurricane genesis, Gray has nonetheless made forays into "theory" (though the results have been decidedly mixed). But the historical context that Mooney provides gives quite a bit of insight into the divergent views that have arisen among partisans in the current hurricane-climate debate.

Mooney covers many of the themes and issues we've discussed here before, but adds his own novel interpretations and uncovers a number of key historical details, in the process of stitching together a compelling narrative. Naturally, there is discussion of the hoopla over the active 2004 and 2005 Atlantic hurricane seasons and the aftermath of Katrina. There is extensive discussion of the high-profile studies by Emanuel, Webster, Curry and coworkers (see e.g. here and here) which, eerily coincident with the record-setting 2005 season, first suggested a detectable climate change signal in hurricane behavior. Due attention, in turn, is payed to the active scientific debate these studies have subsequently generated. Mooney describes the debate over the role of natural vs. anthropogenic factors in observed tropical warming trends that have been related to increased hurricane activity, and there is a fair amount of discussion of the partisanship that high-level NOAA administrators have apparently taken in this debate. But, you might ask, what is the bottom line taken by Mooney? What side of the debate does he come down on? Well, again, those looking for a fight will again be disappointed.

Mooney doesn't come down on any particular 'side' of the debate. Instead, he explores the nuances of the scientific findings and views of the various protagonists, and helps the science and the scientists speak for themselves. For example, he gives Bill Gray credit (and rightly so) for the important contributions he has made to our current understanding of hurricane genesis, and shows a somewhat bemused admiration for Gray as a sympathetic relic of a dying breed of atmospheric scientist. But this does not stand in the way of him criticizing Gray (again rightly so) for his curmudgeonly scorn of current generation scientists, and in particular his somewhat irrational rejection of the science supporting an anthropogenic influence on climate. Mooney articulates his criticism gently, by citing Arthur C. Clarke's "First Law"

When a distinguished elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

There should be no misunderstanding. While Mooney is indeed balanced, he is not completely agnostic either. He recognizes that hurricane characteristics are indeed changing and that, while we may not yet have arrived at definitive answers to the underlying scientific questions, we ought to be concerned.

One could quibble with some details of the book. As we have remarked before, one should be very careful about giving too much weight to any one late-breaking paper. Where there are certainly exceptions where paradigms are dramatically broken on the strength of one groundbreaking paper, science rarely works that way. Instead, scientific understanding generally advances slowly and steadily, based on the results of many independent studies. Mooney however gives quite a bit of weight to the recent article by Kossin et al just published as the book was completed. While this study is undoubtedly an important contribution to the literature, introducing a potentially useful methodology for refining estimates of past tropical cyclone activity in all the major basins, it is hardly the last word (see e.g. the discussion thread in our previous article on the paper). And in places, the implications of that paper are overplayed. For example, Mooney appears in places to imply that the paper's findings challenge the contention that climate change can be tied to increasing hurricane intensity. While the Kossin et al results do challenge some of the findings described in the work by Webster et al (2005) (i.e., the trends for the Pacific and Indian basins), they reinforce the conclusion of positive intensity trends for the Atlantic. Perhaps more importantly, the paper in no way challenges the Emanuel (2005) study demonstrating a close linkage between warming sea surface temperatures and hurricane intensity for the Atlantic. Indeed, those latter findings have been reinforced, not challenged, by more recent work (e.g. Sriver and Huber).

These are minor quibbles however. Mooney chose to walk a minefield in attempting to assess a controversial and quickly evolving field in climate research. He not only succeeded in producing a fair and accurate description of the science, but provides us a fascinating read as well. There is a good chance the book will achieve a very wide readership. If so, then Mooney has performed a real service by helping communicate a subtle but important topic within the scientific discourse to the person on the street.

Note: Chris Mooney has provided us with an early copy of Storm World and we're reviewing it before the official publication date–July 9–so you can't get the book yet in stores. However, you can order it on Amazon.com. You can also visit the book website for more information (including an excerpt of the first chapter).

[Alex Tolley]

Real scientists know that the hurricane science is not yet understood enough to make definitive statements.

[Alex Tolley]

wakingthe line: "I don't think Anne is ranting at all, Alex. Global warming theories predict more intense hurricane activity. We are observing such activity.

Occam's razor suggests that skeptics like yourself should come up with better arguments than, "we can't explain it, but That's probably just an erratic climate." My personal belief is that we are just entering a climatic Kondratieff upturn, but I won't be publishing my case without further evidence."

1. I'm not commenting on GW skepticism, but about anne's response to comment that has no evidence that the speaker is a GW skeptic. (Even if he was, why use such an abusive approach?)

2. You make the exact same error as anne. You have taken my annoyance at anne's conversation stoppers as evidence that I must therefore be a GW skeptic.

I am NOT a GW skeptic. Given that piece of information (go check my other comments on this website if needed), how would you interpret my comment now?

As a general rule, it is better to read what people say, rather than attach stories to the speakers based on your prejudices. That's a classic logical error.

[bigTom]

"As a general rule, it is better to read what people say, rather than attach stories to the speakers based on your prejudices. That's a classic logical error."

A good point. On a topic such as this, where we have seen too much politically motivated stuff arise, it is all to easy for us to too quickly conclude after reading the first paragraph "oh no, another one of these!". Once we've done that it can be a little bit hard to discern the subtler points the writer was trying to convey. It would probably be better to read once, calm down, and reread with the question in mind "is this really what I thought it was?".

[walkingtheline]

I don't think anyone who knows what a Kondratieff cycle is could take my comment too seriously, Alex. It's reasonable to prefer parsimonious theories with predictive power over unspecified claims that variables are moving in long-term cycles no-one understands.

Anne is championing the former. You appear to associate "real science" with the latter. I guess I'll just stick clear of the fray.

[Tim Worstall]

Anne, if you want to refute my point, you might try actually refuting my point. Laying about you with accusations of GW denialism (no, I'm not a denialist, nor even a sceptic) doesn't help.
It's terribly simple, read what people write and respond to that.

[anne]

Immediately after Brad DeLong posted the carefully framed and cautious comments by Chris Mooney, the bashing began.

"Mr Mooney is being more than a little disingenuous...."

"He is almost self-refuting...."

Both comments are of course nonsense, and meant only to discredit the attention Mooney is calling to the possibility of weather extremes resulting from climate changes.

Adding the following statistics tautology, "It's also true that the longer you measure a variable the more likely you are to get extremes" to the criticism struck me as adding to the unfairness of the criticism. However, as was pointed out, I may have been wrong in attributing an intent to confuse the comments by Mooney by this comment.

I was not fair, to Tim Worstall and should have explained that in the course of gathering statistics there will almost always be "extremes" recorded from ranges of reasons even to measurement difficulties.

I was unfair to Tim Worstall.

[Tim Worstall]

Fairly said Anne.

My own understanding of the hurricane issue is that while we would expect GW to increase intensity (although not, necessarily, incidence) we also have over laid that a known multi-decadal cycle of variances in incidence: so pulling the GW effect out of any short term differences is going to be very difficult indeed.