Very interesting study! Researchers need to do more of this in-depth analysis of the historical record to determine if the data being used is reliable. Much has changed in the methods and instruments used to record weather events like hurricanes. This is what science should be, namely, objective, not biased in favor of one argument or its opposite.

Now, if we could get the folks over at NASA to stop altering the temperature record then we might learn more about what's REALLY happening in earth's climate.

Hurricanes are NOT increasing in frequency or intensity nor are they being influenced by the slight warming our planet has experienced in recent years. Other scientists have looked at this GW claim from different perspectives and reached the same conclusions. Some scientists have even concluded that warmer ocean waters act as a deterrant to the formation of hurricanes.

When will the AGW believers acknowledge that there is NO scientific evidence to support the global warming - increased frequency/intensity hurricane connection? Probably never.

Good Lord! No one thought of doing this before?

Nobel Laureate Al Gore says that global warming is causing a catastrophic increase in hurricanes and hurricane damage. Who should we trust?

The Nobel committee has a very rigorous selection process and it is extremely unlikely that they made a mistake in their choice last October.

Storm records prior to about 1900 do indeed appear to be unreliable, but this doesn't mean that the number of storms is not associated with sea surface temperatures. This is a graph of 17-year central moving averages of NH sea surface temperatures and the number of named storms in the Atlantic basin. You can clearly see the problem before about 1900 there. But don't believe your own eyes if you don't want to, folks.

Big surprise, since the last two years have been flops for US hitting hurricanes. This year looks like it may follow suit. However I am sure if hurricanes were still making headlines like they were for several years up through 2005, their study would have said just the opposite. If this year turns out to be a big hurricane season, look for the flip flop on this story. This is why I don't buy the AGW game, studies are always massaged to fit whatever is the flavor of the week(drier Summers, we said AGW would cause that, wetter Summers, we said AGW would casue that). P.S. I want my Summer back, but I fear it is gone.

I think updates like these continue to make the skeptics' point:

1. We have a long way to go before we truly understand the drivers of long term climate change.

2. Much of the historical temp and weather event data used by the alarmists, while worthy of our investigative interest, should be viewed with a skeptical eye.

That, my friends, is science.

I wonder if the NHC will go back to naming only tropical systems and stop giving names to hybrid storms.

Big surprise, since the last two years have been flops for US hitting hurricanes. This year looks like it may follow suit. However I am sure if hurricanes were still making headlines like they were for several years up through 2005, their study would have said just the opposite.

That's why anecdotal data should have no bearing on these types of analyses. If you look at storm data, you will see that (1) it is very noisy, meaning that there are considerable random fluctuations from one year to the next, and (2) the 2005 season was a 50-year season, so it should not be used as some sort of benchmark.

Tom,

The science officer at the National Hurricane Center wrote a paper along the same lines last year.

http://www.aoml.noaa.gov/hrd/Landsea/landsea-eos-may012007.pdf

My understanding is that warming causes a greater increase at the poles. This in turn lessens the "difference" between the poles and the equator. It is this "difference" that brews up hurricanes, not the general increase in temperatures, as I understand it.

We are entering the end of the warm AMO, according to some. Although the Atlantic "remembers" the warming, and holds the warmth, the poles should start cooling. This will increase the "difference," and consequently the number of hurricanes. These hurricanes will gravitate to the western side of the Atlantic, because that is where the warmest water pools at the end of the warm AMO. Therefore New England could be hit by more hurricanes, as it was back in 1938, 1944, 1954 (three) and 1955 (two).

Should New England be hit this year, many will be astonished by the damage. Both the 1938 hurricane and Carol in 1954 knocked down huge numbers of trees, especially up in the hills.

I am planning on being without power for three weeks. I think one of the most frustrating things will be that I will not be able to visit this site, and debate the people who call the damage "unprecedented," and blame Global Warming.

It has happened before, but in the old days the old-timers just looked on the bright side. "Reckon we won't have to buy any firewood this year." Also, even when they had indoor plumbing, they still had the old outhouse in the back yard, though it wasn't used much.

Can you imagine a modern, suburban neighborhood trying to go three weeks without their toilets flushing?

Picky detail: the name of the derived SI unit is

degrees Celcius

not 'celcius'.

"Very interesting study!"

Gotta love it. When an agency like NOAA comes out with a study supporting AGW, Deniers whip out their usual rhetoric about how they are fudging data in an attempt to increase government control over our lives, redistribute wealth AND....*drum roll please*....RAISE TAXES!

Yet, when they come out with a study that is skeptical of some component of AGW, they say it's "good science."

In any case, I've always been skeptical of the link between AGW and hurricane frequency, and this study doesn't change the fact that more study is needed. However, we do know that water temperature has some correlation with more hurricanes, because we note that hurricane frequencies and intensities increase when the AMO is positive (see Joseph's graph). If there was no correlation, then there should be just as many hurricanes during negative AMO phases as compared with positive ones.

Not exactly tropical, but here's a mid-month update on this summer's ice melt from NSIDC:

http://nsidc.org/arcticseaicenews/index.html

Hey guys,

I have been away visiting some of my girlfriend's family in west central Pennsylvania last week. For anyone interested, The first part of last week was quite warm there, but the second half was chilly, shockingly so to one used to summer in North Carolina (at least in the Piedmont and coastal plain).

Mark,

NOAA is a large organization comprised of many individuals.

I understand your love of the the Borg concept, but not everyone thinks or acts the same way - at least not yet.

Patrick - I appreciate your providing the reference. I am aghast. Common sense and a brief glance at some very simple plots suggests there is a negative bias in the early counts, and yet only recently climate scientists have gotten around to examining this?

Great study. Interesting that other studies show a link between the AMO and hurricane frequencies. Still, there is a lot to be learned.

It is a known fact after all that warmer water = stronger hurricanes. Measuements can be taken to verify that link. So, one can see why certain people link global warming with increasing hurricane intensities.

Why didn't they think of this before? They did, but how do you figure out how many storms there were in the early/mid 1800's with very few records of those storms? Guess? Use computer models?

"We have a very solid theory that links storm intensity to sea surface temperature," said James Kossins of the University of Wisconsin, Madison.

"But although an increase in storm counts is sometimes implicitly associated with global warming, it doesn't stand up to re-analysis, and we don't really have a solid scientific theory for why that is."

Mark and Joseph,

Do GHGs cause the fluctuations of teleconnections like the AMO and ENSO?

Joseph,
The graph you posted seems highly suspect. First, why are all the temeperature anomalies negative? How is that even possible? What is the base from which it went negative? Secondly, the plot of named storms is WAY OFF. There has never been a time when the moving average for named storms has approached 29 and it certainly didn't hover between 22 and 24 for 50-60 years from the 1930s to the 1990s. I also assume you're talking about named storms in the Atlantic since the graph doesn't specify. But here is a website with real data on it: http://www.nhc.noaa.gov/pastprofile.shtml
In the top figure, you'll see the average number of named storms in the Atlantic historically is 10.1. Your graph of the moving averages doesn't even approach 14 in the lowest frame.

CALEB i had the experience of going through hurricane bob in the early ninetys while vacationing in connecticut you are right we didnt have electricity for 3 days and there were leterary hundreds of trees knocked down. as i understood i the ground was so soaked from the advancing heavy rains that the root systems were incapable of maintaining the grip against the ensuing winds. one visual ill never forget was an unattatched garage with a huge tree leaning up against it from theback. you could literally see the strain of the garage as it held the weight of the tree. it was amazing though everone did what was necessary to survive freezer food was used up stores managed to stay open and eventually power was restored. next time im sure that will happen again people will make do.

when i was a kid (Mccain is old enough to be my older brother) storms didnt get named until they were full fledged hurricanes. when did things change to wher every atlantic or gulf low get named anyone

Re: Joe

Please will you stop trotting out that chart on various sites as if it were defacto proof that hurricane / ts frequency has increased perfectly in step with temperature. (Sorry Emanuel, Knutson, Landsea, NOAA, Vecchi, Klotzbach, Michaels, Pielke, Hoyos, Bengtasson,
Sugi, Yoshimura etc. Joe says you're all wrong and storm frequency has increased, "so there".)

This paper contends that storms prior to the mid half of the century were not as likely to be recorded (because they didn't go through the shipping lanes)and there is therefore some correction factor needed.

Therefore, (stay with me sport), the data for the left half of your chart is not representative of the actual number of storms. Why don't you multiply your pre 1960 storm numbers by 1/3 as the paper suggests, recompute your moving average and post that chart?

For years I've thought the increase in tropical storms was mostly a function of the powers of observation. Couple that with hybrids named and the rush to name any system close to land despite no ship,buoy,or station observations of 39 mph sustained wind and you have an increase in named systems. I don't care if a plane finds 40 mph winds at 1500-2000 feet above the surface. That doesn't validate their own standard for a name.

Ronnie

"Why didn't they think of this before? They did, but how do you figure out how many storms there were in the early/mid 1800's with very few records of those storms? Guess? Use computer models?"

Well, you act as a professional, responsible scientist would: either (1) employ methods such as Vecchi and Knutson or Landsea used to estimate the bias, or (2) refrain from making claims that "global warming" is causing an increase in storm frequency when you can't quantify how much of the observed increase is due to negative bias in the earlier storm counts.

Let me rephrase that: act as a responsible student would act. This is elementary.

http://www.gfdl.noaa.gov/~gav/REPRINTS/VK_07_RECOUNT.pdf
I've skimmed to page 8. I'd think more storms wouldn't overlap at the same time. That is, more storms means storms starting earlier and ending later, not overlapping at the same time. I'd expect the latter effect to manifest as stronger storms.
On page 8 is an assumption that seems to render the paper pointless. But maybe the authors have just horribly misstated their intent.
Assumption #7 says it is assumed modern day TC are representative of TCs in the past in terms of numbers and strength. It is even spelled out 3 paragraphs later that assumption #7 acts to oppose any real trend. Isn't that epicycles? The paper is an attempt to fill in missing observational data pre-satellites. But if there is a real trend over the 20th century of more (or less) hurricanes, assumption #7 automatically smooths it out, doesn't it? I can't skim the rest of the paper until a know the effect of assumption #7. To me, assumption #7 postulates there must not be any changes in trends, fills in enough storms in the past to = presnt, then uses this as observational evidence.

Just for the record, Brett, this post and in particular its headline are a great example of the sort of misunderstanding to which you're prone. The paper made no prediction at all about the effects of future warming. You can confirm that for yourself by reading the complete paper.

As well, why note this particular paper and ignore numerous other recent ones? At best, your readers are left confused as to the state of the science.

FYI there is another recent paper (see also this FAQ) by some of the same authors that does argue for essentially no increase in 21st-century Atlantic basin tropical cyclones, but note that even this one avoids making a long-term projection. Partly this is because the modeling approach used in the paper is novel in a number of ways and so requires further work, but also because of the powerful argument (paper) that sufficient warming must ultimately increase tropical cyclone numbers as well as intensity. In a nutshell, the argument is that greatly increased tropical cyclone activity is the only available mechanism for keeping the tropics as cool as they were in past climates that were much warmer overall than the present one.

I won't bother asking you to fix the post since you never do.

I am not disputing this for a second but wouldnt a warmer climate lead to an increased temperature gradient between the tropics and polar regions, increasing the frequency and intensity of tropical storms?