From a Clemson University press release, another peer reviewed study refutes the “global warming to hurricane” linkage that supposedly is causing stronger storms.
The increasing frequency of storms in the last 50 years is to be expected, due to better reporting and improved technology like satellites, Hurricane Hunter planes, and Doppler Radar. NOAA agrees on the improved reporting issue in a study here.
This echoes what I reported on April 11th 2008 about Emanuel’s findings as well as what I reported on February 21st 2008 from Roger Pielke Jr. and Chris Landsea at the National Hurricane Center. On May 15th, 2008, Tom Knutson, a meteorologist with the National Oceanic and Atmospheric Administration’s fluid dynamics lab in Princeton, N.J. reversed his position on the issue in an AP story and argues “against the notion that we’ve already seen a really dramatic increase in Atlantic hurricane activity resulting from greenhouse warming.”
Plus, according to Florida State University’s Ryan Maue, Accumulated Cyclone Energy has hit a 30 year low. The Global Warming linkage simply isn’t there.
CLEMSON — In a new study, Clemson University researchers have concluded that the number of hurricanes and tropical storms in the Atlantic Basin is increasing, but there is no evidence that their individual strengths are any greater than storms of the past or that the chances of a U.S. strike are up.
Robert Lund, professor of mathematical sciences at Clemson, along with colleagues Michael Robbins and Colin Gallagher of Clemson and QiQi Lu of Mississippi State University, studied changes in the tropical cycle record in the North Atlantic between 1851 and 2008.
“This is a hot button in the argument for global warming,” said Lund. “Climatologists reporting to the U.S. Senate as recently as this summer testified to the exact opposite of what we find. Many researchers have maintained that warming waters of the Atlantic are increasing the strengths of these storms. We do not see evidence for this at all, however we do find that the number of storms has recently increased.”
The study represents one of the first rigorous statistical assessments of the issue with uncertainty margins calculated in. For example, Lund says “there is less than a one in 100,000 chance of seeing this many storms occur since 1965 if in truth changes are not taking place.”
He adds, “Hopefully such a rigorous assessment will clear up the controversy and the misinformation about what is truly happening with these storms.”
The study, submitted to the Journal of the American Statistical Association, also found changes in storm pattern records starting around 1935. This was expected at the onset of aircraft reconnaissance, which allowed record-keepers to identify and document storms occurring in the open ocean.
While the study did conclude that more storms are being documented, researchers found no evidence of recent increases in U.S. landfall strike probability of the strongest of hurricanes. Lund notes that “because these types of storms are so uncommon, it will take many more years of data to reliably assess this issue.”
The key words are “have been observed”, and for that matter, recorded except for a notation in some ship’s log. Most hurricanes don’t make landfall. In the 19th Century the number of ocean shipping routes increased, along with more shipping, along with wireless radio.
First in the 20th Century came the airplane, and many which would not have been noted at all were then recorded. As over ocean air routes and numbers of these flights increased, more were noted and recorded than otherwise would be. Then came satellites, and all of them are now observed, no matter how small or insignificant to humans they might be.
Hmmm, 2 total this hurricane season so far, I do thinik. I don’t pay as much attention since I moved to Phoenix, AZ from Jacksonville, FL 5 years ago.
There are one or two disclaimers:
“While the study did conclude that more storms are being documented, researchers found no evidence of recent increases in U.S. landfall strike probability of the strongest of hurricanes. ”
and:
“The increasing frequency of storms in the last 50 years is to be expected, due to better reporting and improved technology like satellites, Hurricane Hunter planes, and Doppler Radar.”
So please Mr Lund, is it possible that there isn’t a necessary increase in number of storms if current technology allows you to capture more of these events?
An increase in the number of tropical storms and hurricanes but not an increase in the strength of those storms? I was looking for words to the effect that the proportion of the various categories of storms remained constant but it didn’t say that. it did say the number of big storms making landfall hadn’t increased, which leads me to think they’re counting a whole lot more smaller storms. That makes me think they’re just getting more observant but otherwise things haven’t changed much.
enduser (11:40:38) :
I have asked this question before, and gotten no reply, so I will ask again.
Through what possible mechanism can an el niño event raise the mean global temperature?
Let me have a stab at this. For a variable length of time an excess of solar energy becomes stored in the Pacific Warm Pool. The storage is largely at depth, however, so that this energy cannot reach the surface and be transported into the air. During an El Nino this water becomes spread over a large ocean area in the Pacific and transport to the atmosphere is now quite rapid. Temperatures over a large fraction of the globe increase. There is increased water vapor transport also, and perhaps even an enhanced radition effect from this water vapor.
At this point the global mean temperature is above an equilibrium value (supposing that the global mean temperature is a meaningful measure of equilibrium in the first place.) One might expect a return to equilibrium rapidly. However, there are a number of feedback mechanisms that can prevent a rapid return to equilibrium; most specifically a feedback involving cloud cover, or even others involving albedo other than clouds. I doubt that anyone can say with confidence what is the actual time span required for return to equilibrium, but decades needn’t be beyond the question. Now organize a number of unusually strong el ninos in succession and one might even get an impression of temperature trends characterized by the term “climate change.”
Well I’ll take professor Lund’s assertion at face value; that they just analysed the record; fair enough. If we want to investigate the meaning of this, we probably have to look at the raw record; which if I understand correctly is summarised (numbers) in his graph of numbers of cyclones.
I do have one criticism of the method of presenting the results.
Presumably each and every storm (cyclone) is a single unrelated event, with no known linking mechanism between storms. They presumably happen as random events; admittedly in a framework of seasonally varying weather patterns; and by happenstance, you count a certain number that meet some criterion in an arbitrary 12 month time interval.
Just as the individual cyclones would seem to have no cause and effect linkage to each other; so too, one would expect the annual counts to be unrelated as well.
So to me it makes more sense to simply plot these annual totals as a scatter diagram of dots.
Linking the dots as if the graph represents some continuous function makes no sense to me. If somebody can fit this function to some mathematical equation having fewer parameters than the number of plotted dots, then I would change my mind; but as it is, the zig zag line shows no ability to predict what the next point to be plotted should be; or even the direction of the next move; but a casual glance might suggest that if one adopted the rule; “Whatever it did for the most recent move, it will do the opposite for the next move.” The data doesn’t adhere rigorously to such a rule, so it can’t be the correct rule, which is why I say the direction of the next move is not predicatble, nor is the extent of that move.
I hate to keep whipping a dead horse; but dare I suggest that the Nyquist theorem does not justify the reconstructed signal evidenced by this zig zag graph; so it should be left as a dot scatter plot.
(Fake name. Snipped entirely. A lot of your time was wasted writing that comment, eh David? -mod.)
Dear Mr. Lund,
I see that you are a professor of mathematics, so when you say: “And yes, we do find a change (increase) in counts circa 1995 that has no easy explanation.”, I can only assume that you are not aware of the climatological work that has been done on this issue.
While the mechanism for many natural climate cycles is not well understood, there is no question that these cycles exist. Often, they exist in concert with other cycles, each one varying at their own rate, and producing results that are never exactly the same each time they manifest. Yet we can and do recognize these cycles, the most prominent one being the ENSO events. Evidence for multi-decadal events is also quite robust. It was through such recognition that the increase in Atlantic Hurricane activity in the mid 1990s was predicted long in advance.
Your broad statement that there has been an increase in the number of storms since 1965, while true, seems designed to support an AGW cause. The more accurate statement, which you made in the comments above, supports the idea that natural variability is primarily responsible for the observational data, as AGW can not explain the lack of a trend from 1965 to 1995, with a sudden step change thereafter.
With no evidence of a human influence on Atlantic Hurricanes, you have made a statement that implies that there might be a human influence and most certainly will be used that way. I find it extremely hard to believe that the statement was made with no intent to support the AGW argument. Your comment above was much more descriptive (although still scientifically incomplete) than the ‘general increase’ statement being fed to the press.
This story says there are more hurricanes. But this one below says there are fewer.
http://wattsupwiththat.com/2009/09/22/global-warming-more-hurricanes-still-not-happening/
Who to believe?
It seems there isn’t even consensus on basic facts.
To amplify on my point about the method of presenting the data; my understanding of Professor Lund’s graph is that there is a single point plotted for each calendar year; or perhaps for some other 12 month period.
By connecting the dots; one is led to believe that intermediate data can be interpolated between the plotted point.
Now I can see in principle how one could take a running 12 month total (of maybe monthly/weekly/daily) cyclone counts, which could then be plotted as a continuous function with actual computed data between the annual points; and presumably such data could be generated if in fact the time of occurrence of each and every cyclone has been captured.
If in fact such a running 12 month total were generated, one would expect to see the frequency spectrum of the plot more clearly, and I dare say such a plot would point out the fallacy of connecting the annual dots as in the presented graph.
Other than that, I have no quarrel with the study; it would be nice if someone with some specific climate or weather data on each of these storms could correlate such data with just Prof Lund’s cyclone counts.
But it is interesting to point out that “global temperature” anomaly data such as GISStemp; that purports to have a long historical record (well 150 years) also suffers from the fact that while the data has been gathered, the construction workers have been continuously working on building the laboratory; and the way it is today, is nothing like the quanset hut shack that existed at the start of the study.
Climate scientists tend to act as if they have been monitoring a static system for long periods of time; whereas in fact the system has been under constant construction since the first such measurments were taken.
And as Anthony’s survey of the GISStemp data sites has shown; some parts of the system have decayed, rather than been enhanced.
There’s not much Professor Lund can do about the fact that his system was also a work in progress as far as the constancy of data gathering methodology.
I’m sure that just pointing out that the data source itself has been under constant modifications; is itself a valuable piece of information, that should tempera the desire to read too much into the results (climatically)
As far as I can tell this report is only good news for the anti-AGW contingent. No increase in stronger storms is the opposite of what AGW proponents have been claiming. As indicated in the article, there’s an obvious explanation for the increase in storms … observation.
Looks pretty cut and dried to me.
enduser (11:40:38) :
Kevin Kilty (13:52:03) :
Suggestions for reading about el niño events raising the mean global temperature:
http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of.html
http://bobtisdale.blogspot.com/2009/01/can-el-nino-events-explain-all-of_11.html
The US landfall record gives 76 events (category 1 or above) for the past 50yrs, and 97 events for the previous 50yrs.
With category 3 and above, there were 26 events in the last 50yrs, and 39 events in the previous 50yrs. http://www.aoml.noaa.gov/hrd/hurdat/ushurrlist18512008.txt
Ships can sail away from storms, the coast cannot be moved.
The chart shows a rising slope starting in the 1970’s, consistent with the increase in satellites. This seems analogous to the number of tornadoes rising along with the increased availability of weather radar. The lower ACE index is consistent with the lower number of severe tornadoes despite the higher number of reported tornadoes.
The only count that would eliminate this bias is the number of hurricanes making landfall.
@Patrick Davis (04:36:45) :
“King of Cool (03:10:49) :
Homo praesumitur bonus donec probetur malus?”
Can I have that in proper POHM England please?
Since you asked nicely, ” Man is presumed innocent until proven guilty.”
I presume King of Cool’s point to be (and I agree) that, recognizing the myriad natural factors in climate variability, Man should be presumed innocent of any contribution until proven guilty. It seems that the opposite POV is in operation in most of climate science these days. Instead of searching for the truth, they seem to assume Man is guilty and are trying to find as many ways possible to prove it.
@Robert Lund-
Thanks for stopping by. The above comment is not directed at you, as I have not yet had a chance to read your study. But I would caution that very precise wording in your conclusions is necessary or people from both sides of the AGW debate will take a study’s results to places you never dreamed of them going.
To those that answered my El Niño question: Thanks.