A leading hurricane scientist disputes claims that global warming has made hurricanes worse.
Chris Landsea, science and operations director of the National Hurricane Center in Miami, said the notion that global warming is causing an increase in hurricanes gained widespread attention after the stormy seasons of 2004 and 2005.
But that perception is wrong and the statistics don't bear it out, Landsea told about 200 students and professors in the auditorium at USC's geography building.
Further study continues to show that hurricane activity occurs in cycles of 20 to 45 years, he said. Even though the seasons of 2004, when four hurricanes bashed Florida, and 2005, when Katrina devastated New Orleans and neighboring parts of the Gulf Coast, seemed shocking, they were no more intense than some storms in the early part of the 20th century and in the 1930s, Landsea said.
The 1926-1935 period was worse for hurricanes than the past 10 years and 1900-1905 was almost as bad, he said. So it is not true that there is a trend of more and stronger hurricanes.
"It's not a trend, it's a cycle: 20-45 years quiet, 20-45 years busy," Landsea said. Scientists currently have no idea what causes the time period.
What makes the recent storms seem worse is the amount of damage, and that is because of the amount of people and their structures on the coast, elements that barely existed in the early 1900s. ...
"An Inconvenient Truth," the book by former Vice President Al Gore, also persuaded some people that global warming is contributing to hurricane frequency and strength, Landsea said.
But facts that also refute the theory are that tropical storms are weakening and becoming less frequent in all oceans except the Atlantic, he said.
If the storms were caused by global warming, they would be getting worse everywhere, he said.
You may remember that global warming apocalyptics predicted that last year's hurricane season would be even worse than 2005, the year of Katrina. In fact, though, no hurricanes made landfall in the United States last year. In a piece published in August 2006, Weatherstreet.com reflected, "Media reports over the last year have suggested that, since global warming will only get worse, and last year's hurricane activity was supposedly due to global warming, this season might well be as bad as last season." But it wasn't.
Part of the reason for the slow season is that tropical western Atlantic sea surface temperatures (SSTs) are running about normal, if not slightly below normal. ... The cooler SSTs in the Atlantic are not an isolated anomaly. In a research paper being published next month in Geophysical Research Letters, scientists will show that between 2003 and 2005, globally averaged temperatures in the upper ocean cooled rather dramatically, effectively erasing 20% of the warming that occurred over the previous 48 years.
Catch that? In only two years, a fifth of the warming that had occurred in almost a half-century was erased. Twenty percent of the warming erased in four percent of the time. No explanation seems to be forthcoming from global warming apocalyptics as to how this cooling occurred, since they blame human activity for the previous warming. Well, folks, if you're going to blame us going up, you're going to have credit us going down.
Actually I've heard some of both. Some scientists predicted that warmer waters would prevent more hurricans in general, but would speed up those hurricanes that formed (and moved) over warmer waters.
Although I have no technical knowledge of this field, it does seem that theory is trying to jump ahead of evidence in the hurricane field, accurate hurricane tracking data is fairly new, and it's going to take awhile before there's enough data to make an accurate theory.
I've tried to keep my respiration to a minimum the last couple of years, i think im really having an impact.
If memory serves, Landsea noisily resigned from the IPCC committee a year or so ago because they were misrepresenting the science about hurricane frequency.
Isn't there a difference between saying "Global Warming can cause an increase in the intensity and frequency of hurricanes" and "GW is causing the current increase ... that we are seeing" ?
I'd expect that in an era of global warming, the less frequent cycles would still produce more hurricanes than previous (less frequent) cycles, and those hurricanes could be more intense as well. So instead of 5 hurricanes a year (a light era, compared to a "busy" era of, say 15/year), with every 7 being a level 3 or higher, we see 6-7 hurricanes, with every 5 being a level 3 or higher. It sounds like there are a couple of arguments that are somewhat unrelated that are being mixed together here.
The IPCC theory isn't even a theory, in fact it isn't even science. These "scientists" are clutching at straws, holding them up to the sun and declaring them gold. Their so-called evidence will wither and crumble away soon enough, hopefully before our beloved politicians invest zillions of dollars trying to stop an unstoppable normal temperature fluctuation.
Gee... life was so much simpler when we could blame all these pesky quirks of weather and climate on el nino. Oh, for the good old days!
DaveK
It's the liberals! It's the liberals! Everyone knows that global warming is nothing but a socialist plot intended to drain our precious bodily fluids; Thank God someone has finally found the courage to denounce this Communist conspiracy. It's just like the tobacco companies; like glocbal warming, no one hase ever demonstrated a causal relationship between smoking and lung cancer. But because of appeasement, defeatism, surrender, cowardice and treason, the tobacco industry gave into political correctness, and are now admitting that smoking actually causes cancer. Outrageous! As baqd as the liberals and global warming.
There's no plot, just poorly interpreted data and overagressive envirogroups forcing an unsubstantiated claim down a gullible public's throat.
It seems like people need to be a bit more careful with what they claim. Namely, while alarmists and popularists were hyping Katrina and similar hurricanes as caused by AGW, to the best of my knowledge the scientific community did not. Indeed, there seemed to be a concerted effort to avoid drawing the connection, by the better informed weather commentors.
It is a strawman to claim that the IPCC report or the consensus of climate scientists in general, were trying to show causation between the increased 2005 hurricane season and GW. From looking at various weather/storm/hurricane/climate websites and blogs (in which I have been interested for quite some time, and even had a relative displaced by Katrina to boot...) I would conclude that the informed and serious AGW students know better than to draw causality in these situations.
Regarding the loss of heat energy in the upper ocean during that 2 year period, I assume you are referring to this paper:
http://www.agu.org/pubs/crossref/2006/2006GL027033.shtml
Certainly an interesting observation, and I did not bother to search for any replies to the paper in other journals, but possible sinks for that energy are the lower portions of the ocean, evaporative cooling, chemical reactions, etc. If you are claiming that this disproves GW, however, then you would be misled, as the question that needs to be asked is where that energy went, not that it was there in the first place.
Just to make sure the record is clear, here is what the lasted released IPCC report (the Summary for Policy Makers) says (on pg 12, emphases mine):
"Based on a range of models, it is likely that future tropical cyclones (typhoons and hurricanes) will become more intense, with larger peak wind speeds and more heavy precipitation associated with ongoing increases of tropical SSTs. There is less confidence in projections of a global decrease in numbers of tropical cyclones. The apparent increase in the proportion of very intense storms since 1970 in some regions is much larger than simulated by current models for that period. {9.5, 10.3, 3.8}"
The concept that the number of tropical cyclones would decrease had been discussed for some time among the weather blogs. The indications are there but obviously there is not a great amount of confidence in the proposition. Thus any alarmist (on web, radio, TV) who trys to claim that the AGW will increase the number of hurricanes is running counter to what the IPCC has actually said.
Landsea's arguments counter mostly the talk of hurricanes you are likely to see in the press, not the Scientific journals or the IPCC report(s). In the weeks and months following Katrina you could read all kinds of sensantionalistic and ill informed claims in many (if not most) US news organs.
Most of the hyperbolic claims on the global warming/hurricane connection resulted from one paper, (Mann, M.E., Emanuel, K.A., Atlantic Hurricane Trends linked to Climate Change, Eos, 87, 24, p 233, 238, 241, 2006.) To say this paper has been "challenged" would be an understatement. Landsea has done an admirable job highlighting the weaknesses of Mann and Emanuel's assumptions (and "assumptions" are EXACTLY what they are.) Basically, Mann and Emanuel couldn't make a case for increased frequency or intensity from the unvarnished data itself, so they invented a measurement "technique" (PDI) that played upon the uncertainties of earlier measurements as opposed to recent observations and "voila!" that produced an "effect."
For example, Mann and Emanuel claim that "nearly every" hurricane in the Atlanic in the 20th century was accounted for in the Best Track hurricane database. I've done work that seems to indicate that the period before satellite coverage of the Atlantic (I looked at 1907-1966) the Best Track data might be undercounting tropical storms in a range from 77-148 storms.
Looking at data that we CAN be certain of, such as the storms we know about because they actually hit the United States, backs up Landsea 100%.
An Alternative Theory to Global Warming
This article leads to a web site Ice Age Now which aggreagates articles seemingly missed by most mainstream scientists and media. To my non-scientific mind the articles make a good argument for an alternative theory as to why the world oceans may be undegoing a rise in temperature and seem pretty convincing. My gut has always told me that Global Warming theorists blaming man made CO2 as the sole mechanism for the measured rise in temperature is not quite correct. That same gut also says that thinking that puny little man could effect change in global climate throught remediation efforts is the worst hubris.
Disclaimer - This is the first time that I have tried putting live links into a reply here and I hope and pray I do not screw up the main page.
The Hobo
InJapan, your description simply does not match Chris Landsea's version of events at the time. He describes his IPCC colleagues, not the media, as distorting the science for a political agenda.
Robin Roberts: I was only commenting on the final product as we see it, and the discussions I read on weather and climate blogs. The inner workings of various groups no doubt have all sorts of characters and agendas.
Indeed, I would expect that individual scientists involved in the process to try and steer the published results in the direction they see fit. However, that is why peer group review, then at least for the IPCC the different governments' reviews, exist. I hope that individuals (scientists or government representatives) who are involved in the process will, if they see the actual published scientific data being wrongly represented, speak out and stop any misrepresentations before publication.
My concern here is one of accuracy in reporting, which is why I quoted the IPCC summary on tropical cyclones, i.e., as the final result of the process, the IPCC did not conclude that there would be an increase in tropical cyclones, and even raised the possiblity that they might decrease.
In a subject such as Global Warming, where the results of published recommendations will lead to strong reactions, and then onto contentious policies, I think it is important that what has been truly said is understood, before heated remarks start flying. Otherwise we will just end up with fields of strawmen, seas of red herrings, etc...
legaleagle,
it has nothing to do with your bodily fluids or fluoridation. It has to do with the Left trying to justify its ideological grip on the economy, its idea of the existence of the common good and the necessity of a central body to control our own issues. That is, to justify its mere existence.
I won't feel guilty for pointing out loudly the parallelism between the old Socialism and the new ideology (because it is not science) behind GW. Those are facts. I won't feel guilty either for some not being able to overcome the fall of the Berlin wall and their need to make some cash and maybe a post in the government out of hot air.
Consensus Statements
by International Workshop on Tropical Cyclones-VI (IWTC-VI) Participants
bq. 1. Though there is evidence both for and against the existence of a detectable anthropogenic signal in the tropical cyclone climate record to date, no firm conclusion can be made on this point.
Global climate is a dynamic equilibrium of such complexity as to exceed the analytic capacity of mankind - at least for the forseeable future - by so many orders of magnitude as to be essentially unforecastable. That is not to say that we shouldn't try to and aren't now (and won't continue to) making progress in understanding the factors driving the system, but it is to say that we can not make any definitive statements about our (anthropogenic) influence on climate. What we can say, based on historical ice core records, is that global CO2 concentrations have gone up substantially during the period of mankind's agricultural and industrial expansion, and that there's a strong possibility (some would say certainty) that the CO2 increase is due to human activity (burning down the climax forests of Europe and much of N. America and the Amazon, and extracting and burning giga-tera-peta-tons of petroleum, not to mention farting cows). And that the global climate system is very sensitive to atmospheric and oceanic chemistry (CO2, saline, temp, etc. - all factors in the incompletely understood equilibrium), as well as extraterrestrial factors like solar activity and uWave heat rays from space aliens (;=)
Given that we do not now understand the global atmospheric/oceanic/lithospheric equilibrium anywhere near completely, we damn well ought to attempt to minimize our impact on it, since the possiblity of pushing the system past a hysteresis point is not non-existant. The economics of dinking with our carbon-based economy ought to be taken into account, but in a worst-case scenario, it won't matter much if we're wealthy, 'cause we might be real hot and real wet. Politics, liberal and/or conservative, is not a real good tool with which to deal with this problem. "'Tis an anamorphic lens though which we gaze..." and all that.
Probability x Severity = Importance...kinda like a terrorist getting a nuke is highly unlikely but the consequences would be so bad, we gotta do something about it.
Not to be atrabilious or anything...
And much is being done, Seahorse_valley: investment in research on fourth generation nuclear reactors, thermochemical cycles and fusion energy. As the Malthus theory that there won't be enough food to feed the world population has proven wrong because did not considered future technological advances (fertilizers, among others), Global Warming ideology also considers a frozen technological background (which is ironic, the climate will change but the technology won't, though we have fare more evidences of the latter).
BTW, there is a simple argument against oil and gas CO2 consumption among continental Europeans: economic independence. Of course, this point is never used by GW believers, not even by Europeans, probably because it does not justify the questions of the Common Good, the necessity of a Central Authority and the grip on the economy, basic issues in the Leftist credo.
Therefore, in my opinion, the lack of use of this important argument proofs that the GW movement is not really concerned by climate change but by the spreading of its Leftist ideology.
What we can say, based on historical ice core records, is that global CO2 concentrations have gone up substantially during the period of mankind's agricultural and industrial expansion, and that there's a strong possibility (some would say certainty) that the CO2 increase is due to human activity (burning down the climax forests of Europe and much of N. America and the Amazon, and extracting and burning giga-tera-peta-tons of petroleum, not to mention farting cows).
But global CO2 concentrations are still not to the highest levels all time.... hmmmm, wonder where all that CO2 came from each and every time it's happened through history?
And that the global climate system is very sensitive to atmospheric and oceanic chemistry (CO2, saline, temp, etc. - all factors in the incompletely understood equilibrium)
That's hardly a given... in fact, I think the evidence shows the exact opposite. If anything, the global climate system is magnificently resilient.
Given that we do not now understand the global atmospheric/oceanic/lithospheric equilibrium anywhere near completely, we damn well ought to attempt to minimize our impact on it, since the possiblity of pushing the system past a hysteresis point is not non-existant.
Chaos theory would say you're wrong about a hysteresis point, and again, historical evidence doesn't support such a conclusion. Dead coral reefs above sea level tell us that the old sea level was once 20' higher than it is today, without an industrial expansion to push CO2 levels high enough to get it there. 20' higher = Greenland gone, which is one of the big scare tactics they like to hit you with, but we've already been there and back again, without any outside forces to speak of.
Probability x Severity = Importance...kinda like a terrorist getting a nuke is highly unlikely but the consequences would be so bad, we gotta do something about it.
Not the same. Probability in both cases are subjective, but Severity in the case of nukes is well-defined. Probability in the case of GW is arrived at by non-experimental methods and based on subjective interpretation of historical and current data. However, Severity is even more questionable, as it is based on subjective extrapolation and therefore contains a great deal of uncertainty by definition. Since both factors in the GW equation are basically made up, Importance becomes unreliable and therefore, well, unimportant.