Global hurricane activity has decreased to the lowest level in 30 years.

Cross Posted from Climate Audit

by Ryan N. Maue, Florida State University COAPS

Figure: Global 24-month running sum time-series of Accumulated Cyclone Energy updated through March 12, 2009.

Very important: global hurricane activity includes the 80-90 tropical cyclones that develop around the world during a given calendar year, including the 12-15 that occur in the North Atlantic (Gulf of Mexico and Caribbean included). The heightened activity in the North Atlantic since 1995 is included in the data used to create this figure.

As previously reported here and here at Climate Audit, and chronicled at my Florida State Global Hurricane Update page, both Northern Hemisphere and overall Global hurricane activity has continued to sink to levels not seen since the 1970s. Even more astounding, when the Southern Hemisphere hurricane data is analyzed to create a global value, we see that Global Hurricane Energy has sunk to 30-year lows, at the least. Since hurricane intensity and detection data is problematic as one goes back in time, when reporting and observing practices were different than today, it is possible that we underestimated global hurricane energy during the 1970s. See notes at bottom to avoid terminology discombobulation.

Using a well-accepted metric called the Accumulated Cyclone Energy index or ACE for short (Bell and Chelliah 2006), which has been used by Klotzbach (2006) and Emanuel (2005) (PDI is analogous to ACE), and most recently by myself in Maue (2009), simple analysis shows that 24-month running sums of global ACE or hurricane energy have plummeted to levels not seen in 30 years. Why use 24-month running sums instead of simply yearly values? Since a primary driver of the Earth’s climate from year to year is the El Nino Southern Oscillation (ENSO) acts on time scales on the order of 2-7 years, and the fact that the bulk of the Southern Hemisphere hurricane season occurs from October – March, a reasonable interpretation of global hurricane activity requires a better metric than simply calendar year totals. The 24-month running sums is analogous to the idea of “what have you done for me lately”.

During the past 6 months, extending back to October of 2008 when the Southern Hemisphere tropical season was gearing up, global ACE had crashed due to two consecutive years of well-below average Northern Hemisphere hurricane activity. To avoid confusion, I am not specifically addressing the North Atlantic, which was above normal in 2008 (in terms of ACE), but the hemisphere (and or globe) as a whole. The North Atlantic only represents a 1/10 to 1/8 of global hurricane energy output on average but deservedly so demands disproportionate media attention due to the devastating societal impacts of recent major hurricane landfalls.

Why the record low ACE?

During the past 2 years +, the Earth’s climate has cooled under the effects of a dramatic La Nina episode. The Pacific Ocean basin typically sees much weaker hurricanes that indeed have shorter lifecycles and therefore — less ACE . Conversely, due to well-researched upper-atmospheric flow (e.g. vertical shear) configurations favorable to Atlantic hurricane development and intensification, La Nina falls tend to favor very active seasons in the Atlantic (word of warning for 2009). This offsetting relationship, high in the Atlantic and low in the Pacific, is a topic of discussion in my GRL paper, which will be a separate topic in a future posting. Thus, the Western North Pacific (typhoons) tropical activity was well below normal in 2007 and 2008 (see table). Same for the Eastern North Pacific. The Southern Hemisphere, which includes the southern Indian Ocean from the coast of Mozambique across Madagascar to the coast of Australia, into the South Pacific and Coral Sea, saw below normal activity as well in 2008. Through March 12, 2009, the Southern Hemisphere ACE is about half of what’s expected in a normal year, with a multitude of very weak, short-lived hurricanes. All of these numbers tell a very simple story: just as there are active periods of hurricane activity around the globe, there are inactive periods, and we are currently experiencing one of the most impressive inactive periods, now for almost 3 years.

Bottom Line

Under global warming scenarios, hurricane intensity is expected to increase (on the order of a few percent), but MANY questions remain as to how much, where, and when. This science is very far from settled. Indeed, Al Gore has dropped the related slide in his PowerPoint (btw, is he addicted to the Teleprompter as well?) Many papers have suggested that these changes are already occurring especially in the strongest of hurricanes, e.g. this and that and here, due to warming sea-surface temperatures (the methodology and data issues with each of these papers has been discussed here at CA, and will be even more in the coming months). The notion that the overall global hurricane energy or ACE has collapsed does not contradict the above papers but provides an additional, perhaps less publicized piece of the puzzle. Indeed, the very strong interannual variability of global hurricane ACE (energy) highly correlated to ENSO, suggests that the role of tropical cyclones in climate is modulated very strongly by the big movers and shakers in large-scale, global climate. The perceptible (and perhaps measurable) impact of global warming on hurricanes in today’s climate is arguably a pittance compared to the reorganization and modulation of hurricane formation locations and preferred tracks/intensification corridors dominated by ENSO (and other natural climate factors). Moreover, our understanding of the complicated role of hurricanes with and role in climate is nebulous to be charitable. We must increase our understanding of the current climate’s hurricane activity.


During the summer and fall of 2007, as the Atlantic hurricane season failed to live up to the hyperbolic prognostications of the seasonal hurricane forecasters, I noticed that the rest of the Northern Hemisphere hurricane basins, which include the Western/Central/Eastern Pacific and Northern Indian Oceans, was on pace to produce the lowest Accumulated Cyclone Energy or ACE since 1977. ACE is the convolution or combination of a storm’s intensity and longevity. Put simply, a long-lived very powerful Category 3 hurricane may have more than 100 times the ACE of a weaker tropical storm that lasts for less than a day. Over a season or calendar year, all individual storm ACE is added up to produce the overall seasonal or yearly ACE. Detailed tables of previous monthly and yearly ACE are on my Florida State website.

Previous Basin Activity: Hurricane ACE

BASIN 2005 ACE 2006 ACE 2007 ACE 2008 ACE 1982-2008 AVERAGE
Northern Hemisphere 655 576 383 408 557
North Atlantic 243 83 72 142 104
Western Pacific 301 274 212 167 280
Eastern Pacific 97 204 55 83 156
Southern Hemisphere* 285 182 191 164 229

* Southern Hemisphere peak TC activity occurs between October and April. Thus, 2008 values represent the period October 2007 – April 2008.

The table does not include the Northern Indian Ocean, which can be deduced as the portion of the Northern Hemisphere total not included in the three major basins. Nevertheless, 2007 saw the lowest ACE since 1977. 2008 continued the dramatic downturn in hurricane energy or ACE. The following stacked bar chart demonstrates the highly variable, from year-to-year behavior of Northern Hemisphere (NH) ACE. The smaller inset line graph plots the raw data and trend (or lack thereof). Thus, during the past 60 years, with the data at hand, Northern Hemisphere ACE undergoes significant interannual variability but exhibits no significant statistical trend.

So what to expect in 2009? Well, the last Northern Hemisphere storm was Typhoon Dolphin in middle December of 2008, and no ACE has been recorded so far. The Southern Hemisphere is below normal by just about any definition of storm activity (unless you have access to the Elias sports bureau statistic creativity department), and the season is quickly running out. With La Nina-like conditions in the Pacific, a persistence forecast of below average global cyclone activity seems like a very good bet. Now if only the Dow Jones index didn’t correlate so well with the Global ACE lately…


Hurricane is the term for Tropical Cyclone specific to the North Atlantic, Gulf of Mexico, Caribbean Sea, and the Pacific Ocean from Hawaii eastward to the Mexican coast. Other names around the world include Typhoon, Cyclone, and Willy-Willy (Oz) but hurricane is used generically to avoid confusion.

Accumulated Cyclone Energy or ACE:

is easily calculated from best-track hurricane datasets, with the one-minute maximum sustained wind squared and summed during the tropical lifecycle of a tropical storm or hurricane.


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i wonder if Gore will update his slideshows….

Graeme Rodaughan

Hi Mark,
Under the “Bottom Line” heading
“Indeed, Al Gore has dropped the related slide in his PowerPoint”
So yes – he apparently is no longer officially touting increased hurricanes.


well that’s good. do you think he will go public with a recantation?

Hi Ryan.
Have you included the latest, March 2009 TC Hamish off the East Coast of Australia, a big one going to Cat 5, although it didn’t cross the coast? We also had an intense one 3 years ago, TC Larry (March 2006).
I must add, that apart from these two big cyclones, the East coast of Australia has been relatively quiet for the past decade.

John F. Hultquist

“La Nina falls tend to favor very active seasons in the Atlantic (word of warning for 2009).”
Yes, but that is only one of the four or so variables. Temperature of the top ~200 m of the tropical Atlantic being another. Wonder how that will shake out this year?
This report is very interesting. Lots of stuff to be watching as summer approaches. A Cat. 5 storm named Hamish just brushed up against eastern Australia this week. Nice images in the IR band.

I’m just a simple fellow. No doubt I’m missing something. But the thought that came to my mind on reading this is that that there simply isn’t a “normal” for hurricane activity.
Whatever causes it, and you can argue the forty-odd current theories without being able to prove a single one of them, they happen when they happen.
The undeniable truth, supported by a consensus of some people including at least 20% who have spent a day or two looking at some papers on the subject, is that all the carbon dioxide we are pumping into the atmosphere has caused hurricanes to decrease. This is shocking, hurricanes are a magnificent natural phenomenon and wicked humans are causing them to die just like polar bears (except that polar bears are doing rather well – unless you happen to be a seal in the wrong place at the wrong time, in which case a polar bear is a fluffy knife and fork; but that doesn’t count because the consensus says it doesn’t).
I’m not going to bore everyone with the latest BBC twaddle about the tree-huggers’ conference in Copenhagen, my blood pressure can’t take it.

OT…but have you seen the latest tripe from CNN ?:
(CNN) — The world is facing an increasing risk of “irreversible” climate shifts because worst-case scenarios warned of two years ago are being realized, an international panel of scientists has warned.
Drought, flooding, storms and mass extinction in the future will have a heavy social cost as well. Temperatures, sea levels, acid levels in oceans and ice sheets were already moving “beyond the patterns of natural variability within which our society and economy have developed and thrived,” scientists said in a report released Thursday.
The findings came at the end of a three-day conference in Copenhagen, Denmark, where nearly 2,000 researchers gathered to discuss climate change.
The group called on policy-makers to use all tools available to reduce dangerous emissions of greenhouse gases.
The current climate situation on the planet may be as severe as the worst-case scenarios predicted by the Intergovernmental Panel on Climate Change (IPCC), which issued warnings in 2007 of a future beset by flooding, drought, storms and mass extinction of species.
In its report, the researchers also warned of potential social costs across the planet because of climate change.
Temperature rises above 2 degrees Celsius would lead to climate disruption for the rest of the century and disproportionately affect poor nations, the researchers warned.
“Recent observations show that societies are highly vulnerable to even modest levels of climate change, with poor nations and communities particularly at risk,” the report said.
The conclusions of the conference will be presented to politicians when they meet in Copenhagen in December. It is then that leaders will discuss a new global agreement on greenhouse gas emission levels to replace the Kyoto Protocol, which expires in 2012.

Len van Burgel

Ryan, I posted this at CA, but for the information of other readers repeat it here:
In Australia a willy-willy is not a tropical cyclone, it is a dust devil. However there has been quite some discussion as to the origin of the term. It is believed to stem from the aboriginal language and it is likely that aboriginal people described both a dust devil and a cyclone dissipating inland by the same term “willy willy”. That is why the confusion over the usage of the term. However willy willy is now the accepted terminology for dust devils which are quite frequent, usually innocuous, but in extreme cases can damage buildings. For example the thunderbox in the back yard was liable to be under threat.

Keith Minto

TC Hamish started out as a 5 and descended to a 2 as it paralleled the QLD coast far enough out to sea to avoid land damage. It did a 180 turn at Fraser Is. and petered out as a low.
There are some 1deg. SST anomalies off the coast at 30deg. that may be linked with the onset of Hamish, but on the plus side is some wonderful ocean churning and land rainfall without the harm.

Neil Crafter

Most aboriginal languages had many different words for weather conditions, and I am rather dubious that the name they may have had for a dust devil would be the same word they would use to describe a cyclone dissipating over land. Two such totally different phenomena would not have been described with the one word.


Low to non-existent sunspot cycle.
Lowest level of hurricanes world-wide in 30 years.
The Sun’s electromagnetic energy at a low ebb.
Yes, the Sun has all to do with climate change up or down.
Man? Not so much.

Neil Jones

Off topic
Has “The Cryosphere Today” site changed the colours on its side by side maps to a warmer palette?

spangled drongo

The so called cat 5 cyclone named Hamish was a fizzer. The whole time it was being tracked it did not record winds in excess of 50 knots even in the offshore islands.
It stayed at sea and has now returned to a low pressure system.
It was supposed to have a central pressure of 925mb but the lowest I saw any of the BoM instruments was just over 1000mb [29.55 inches of mercury].

spangled drongo

It would be interesting to know how they get their measurements for the centre of the cyclone with accuracy.


Cyclone (hurricane) activity around Australia is at unusually low levels.
Predictably the Australian BoMs response is to not update their graph.
More recent data here.
So far this summer, I don’t think we have had any landfalling cyclones.
Note the historical data is only reliable for cyclones making landfall.

Parse Error

Mike Strong – I find it very disturbing that the more their supposed “evidence” vanishes before our very eyes in the real world, the more entrenched in their theory they become.

spangled drongo

Mille pardons, I found a wind speed of 57 knots at Double Is. Point on 10th March at 7.15pm. Barometer 1009 mb. [hpa]?

Ron de Haan

mark (20:16:31) :
i wonder if Gore will update his slideshows….


This is my first time posting, after lurking for a few months. This site and CA are some of the best I’ve found for clear discussion. Anthony, you and contributors to this site do a great job.
I’m glad this part of the ‘science’ is now settled, as hurricanes have long been a talking point of the AGW crowd. It’s good to finally have a comprehensive refutation of that specific point. I’d also like to say that I’m very very tired of hearing the phrase ‘researchers warned’ or ‘scientists warn,’ like in Mike’s CNN article. Is it just me or did that kind of phrasing only appear recently (last five or ten years), and mostly in articles about climate change? It bothers me greatly. Seems to me scientists should stick to collecting data and reporting results, instead of speculating about and issuing warnings for the future.


Chris writes: “Seems to me scientists should stick to collecting data and reporting results, instead of speculating about and issuing warnings for the future.”
A reasonable request I think, but in fairness I suspect only a vociferous few “scientists” issue warnings and ultimatums. The press are extremely fond of making up their own ways of describing things. One need look no further than the recent Guardian article ( which asserts that the ICCC is “billed as the largest ever gathering of climate change deniers”. I am certain it was billed as no such thing, nor ever would be. The Gaurdian just fabricated that billing and probably sees no harm in doing so.


off topic but perhaps this should be picked up

Key Message 1: Climatic Trends
Recent observations confirm that, given high rates of observed emissions, the worst-case IPCC scenario trajectories (or even worse) are being realised. For many key parameters, the climate system is already moving beyond the patterns of natural variability within which our society and economy have developed and thrived. These parameters include global mean surface temperature, sea-level rise, ocean and ice sheet dynamics, ocean acidification, and extreme climatic events. There is a significant risk that many of the trends will accelerate, leading to an increasing risk of abrupt or irreversible climatic shifts.

F Rasmin

Keith Minto (22:28:21): Sorry to burst your balloon old chap concerning Cyclone Hamish. You say, ‘….but on the plus side is some wonderful ocean churning and land rainfall without the harm.’ That would have been quite nice without the presence of human fools. A Hong Kong freighter festooned with containers was in amongst that cyclone where it should not have been. Many containers were washed overboard and one of them breached the ship’s hull causing 100,000 litres of oil to be released. The oil has now washed ashore on beautiful beaches and up creeks and rivers. It is considered to be Queensland’s worst environmental disaster on record! The lost containers also contained fertiliser- that if released- with do untold damage to the eco -system!

F Rasmin

Here is a link to that story of the oil spill in Australia.,23739,25179213-952,00.html

Chris 00:45,
I’m just a trifle concerned about the concept that:
“overall Global hurricane activity has continued to sink to levels not seen since the 1970s”
The 1970’s were famous in Australia for some huge MOFOS of cyclones, starting with TC Ada, a ‘Category 4’ cyclone that severely damaged resorts on the Whitsunday Islands in January 1970. It claimed resorts and boats on the Islands of Daydream, South Molle and Hayman, as well as homes near Proserpine where flooding also occurred. 14 people died and total estimated costs were $390 million (in 1970 values).
Following that was TC Althea, which was a Category 4 cyclone when it hit Magnetic Island and Townsville in North Queensland on December 24 1971.
Althea produced peak gust wind speeds between 123 and 145 miles per hour (197 and 233 km/h). Three people died and property damage was estimated at AU$115 million loss (1990 value). On Magnetic Island 90% of the houses were damaged or destroyed. In Townsville houses were lifted from their foundations and most trees stripped of foliage. Althea was also notable at the time, as it had struck a major city.
As well as Althea, the following storms occurred in the Australian Region during the 1971/72 tropical cyclone season:
Ursula, 2 to 16 December 1971 in Solomon Islands area
Kitty, 2 to 5 December 1971 in the Arafura Sea
Bronwyn, 3 to 12 January 1972 in Gulf of Carpentaria
Carlotta, 5 to 21 January 1972 well off Queensland
Wendy, 30 January to 9 February 1972 very intense off Queensland, possible pressure as low as 890hPa
Daisy, 7 to 14 February 1972 off Queensland, caused some flooding near Brisbane
Emily, 27 March to 4 April 1972 off Queensland, eight lives lost at sea
Faith, 11 to 23 April 1972 in Torres Strait and Coral Sea off Queensland
Gail, 11 to 18 April 1972 well off Queensland
Hannah, 8 to 11 May near Papua New Guinea
Ida, 30 May to 3 June 1972 near Solomon Islands causing $70 million damage.
Rhoda, 20 to 26 October 1971 in central Indian Ocean
Sally, 3 to 13 December 1971 crossed coast near Broome, Western Australia.
Tessie, 20 to 27 February 1972 in central Indian Ocean
Vicky, 24 February to 4 March 1972 crossed Western Australian coast at Cockatoo Island.
Angela, 29 February to 3 March 1972 near Cocos Island and Christmas Island
Belinda, 20 to 30 March 1972 near Christmas Island
Carol, 6 to 14 April 1972 in central Indian Ocean
Following that barrage of tropical cyclones, we had a relatively peaceful period until TC Wanda, which existed from 24 January to 27 January 1974 and led to extensive flooding over southeast Queensland. Although this tropical cyclone was relatively weak, it dropped enormous quantities of rain on south-eastern Queensland and north-eastern New South Wales over the Australia Day (26-27 January) weekend, resulting in some of the worst flooding seen in a century. The Queensland state capital, Brisbane, fared particularly badly, with fourteen lives lost and parts of the city submerged under 2 metres of the Brisbane River.
In northern New South Wales, a further two fatalities were reported. The cyclone’s final toll: 16 dead, over 300 injured; 56 homes destroyed, a further 1,600 submerged; 8000 people left homeless.
As an aside, TC Hamish which (thankfully) missed the Queensland coast just in the past week was orders of magnitude larger. It was a Katrina which didn’t landfall.
Cyclone Tracy was a tropical cyclone that devastated the city of Darwin, Northern Territory, Australia, from Christmas Eve to Christmas Day, 1974. It is the most compact hurricane or equivalent-strength tropical cyclone on record, with gale-force winds extending only 48 kilometres (30 mi) from the centre.
After forming over the Arafura Sea, the storm moved upward and affected Darwin with Category 4 winds on the Australian cyclone intensity scale.
Tracy killed 71 people, caused $837 million in damage (1974 AUD) and destroyed more than 70 percent of Darwin’s buildings, including 80 percent of houses.
Tracy left homeless more than 20,000 out of the 49,000 inhabitants of the city prior to landfall and required the evacuation of over 30,000 people. Most of Darwin’s population was evacuated to other cities/towns, and many never returned to the city. After the storm passed, the city was rebuilt using more modern materials and updated building techniques. Cyclone Tracy was a disaster of the first magnitude without parallel in Australia’s history.
The early-mid 1970’s were the most severe years for cyclones that Australia has ever seen.
Any suggestions?

Paul S

FatBigot (21:09:09) :
I’m just a simple fellow.

Sir, I feel you greatly under estimate yourself!

Roger H

COPENHAGEN — Hundreds of leading scientists warned Thursday that global warming is accelerating beyond the worst predictions and threatening to trigger “irreversible” climate shifts on the planet.
This is a headline out of The Detroit News March 12. If you own any beachfront property you had better get rid of it as soon as possible. See:

Steve M.

mark (20:16:31) :
“i wonder if Gore will update his slideshows….”
Maybe WWF will drop their “Golf in a level 5 hurricane” commercials…


If AGW causes hurricanes, what causes lack of hurricanes …?

Bill Illis

Close correlation to the AMO.
(I imagine the AMO isn’t affecting Pacific cyclone numbers but it certainly impacts the Atlantic numbers). (Note the recent decline with the newest Feb, 2009 figures).
A splash of PDO and the ENSO might help explain Pacific cyclone numbers.
Note how they are all in negative territory now.


Hey, Len van Burgel
Thanks for clearing up the definition of “willy-willy”.
You have, however, left me with “thunderbox” to puzzle over;-)

B Kerr

The ACE formula is intriguing me.
If I read this correctly, ACE is Accumulated cyclone energy.
Energy is directly proportional to velocity squared.
But energy is also directly proportional to mass.
“ACE is the convolution or combination of a storm’s intensity and longevity. Put simply, a long-lived very powerful Category 3 hurricane may have more than 100 times the ACE of a weaker tropical storm that lasts for less than a day.”
OK, a hurricane with say max velocity of 100mph would have energy of 100^2 that is 10,000 units.
A less active hurricane with twice the swirling mass with a max velocity of say 80mph would have an energy of 2 x 80^2 = 12,800 units.
Am I right in saying that a massive Tropical Storm would have more energy than a less massive Cat 3? (I’m thinking of my vacation, last August, in SW Florida. Boy did we get it!)
And since “ACE is the convolution or combination of a storm’s intensity and longevity”, then am I right in thinking that a 80 mph Hurricane that lasts twice as long as the 100 mph Hurricane will have more energy?
What is actually being calculated by ACE?
What is the ACE unit?
I am really not sure what ACE is trying to tell me.

Pearland Aggie

spangled drongo (23:14:19)
The Hurricane Hunters fly criss-crossed patterns through the eye and eyewall structure, taking measurements and releasing dropsondes. they can usually find the center of the cyclone fairly accurately. for instances where they can’t find the exact location or couldn’t sample the center, they have fairly accurate correlations and can make a best guess for minimum central pressure. these adjusted readings are rarely more than 2-3 mbar lower than the lowest recorded pressure reading.
hope that helps!

Frank K.

Ryan – Thanks a lot. This was a very interesting article. I’m afraid this information will likely not make it to the MSM to balance the global warming = more, bigger hurricanes hysteria.
I remember the mania that broke out after the 2005 hurricane season – how ** people ** were blamed for hurricanes because they didn’t support radical global warming policies! Here’s a good synopsis of the scientific debate that occurred back then:

Douglas DC

Here are our local records broken for NE Oregon SE Washington-as of yeaterday: Courtesy of Weather Underground.
No it’s not Heat, but cold-quite cold…
Al Gore is full of…..


Re: Chris (00:45:55) :
Totally agree. I have been following the media, the published science and observations for the past 5 to 10 years surrounding AGW.
I think there is a trend – the more data that comes in which refutes that theory of AGW, the more strongly worded, frequent and fantastic the press releases and claims have become from the Alarmist AGW camp.
It tells me 2 things:
1) the science was never there to begin with
2) the Alarmists are panicking and going to even more extreme claims in order to keep the political momentum and public fear up


“Al Gore is full of…..”
…Second Breakfast? 😉

Parse Error

Hmmm, perhaps this sort of thing just might explain what I commented on earlier…

“We need a much stronger sense of urgency,” Ashton said. “We have not begun to close the gap between what we are doing and what needs to be done.”
He added that politicians tended to make decisions based on risks likely to be experienced within the average lifetime and advised scientists to tailor messages accordingly.
Highlighting the worst case scenarios of one to two metre sea level rises over the next 50 years, Ashton argued that the onus was on scientists to make the threat “much more vivid than it is perceived to be”.
However, he also warned against defeatism, arguing that the best way to deliver a world that is six degrees hotter is to tell politicians that the chance of delivering safer levels of two degree warming has already passed.
His comments were echoed by Danish climate change minister Connie Hedegaard, who said that climate scientists needed to “bring their best game” to the negotiating table over the coming months and make their case compelling.

Made-to-order global threats, and free delivery for any climate of your choosing if you get your credit card ready and call now? They may as well hire Billy Mays as Global Climatology Czar at this point…

matt v.

Bill Illis
I agree with you that the pattern of AMO and PDO could explain the posted ACE curve. One of the the common threads between 1970’s and the 2008/2009 periods is both AMO and PDO were negative then [from 1964-1976] and are again neagtive now .PDO went negative 1n 2007 and AMO has been negative in jan/feb 2009. The 1993,1998 and 2006 peaks seem to correspnd to peaks in either the AMO or the PDO or both.


Re: Parse Error (06:04:24) :
“Made-to-order global threats, and free delivery for any climate of your choosing if you get your credit card ready and call now? They may as well hire Billy Mays as Global Climatology Czar at this point…”
(If I wasn’t laughing about this, I’d be crying with dismay on the state of Climate Science)

The data was updated through March 12, 2009, which includes all of Hamish, one of the highest ACE storms of the last couple years. The Southern Hemisphere activity is remarkably weak with many short-lived tropical storm strength cyclones. There just isn’t much time left to make up the deficit.
Also, the 24-month running sum plot has NO smoothing. This plot will always exist and the recent downturn is cemented in history.
The definition of “willy-willy” is rather nebulous since it is slang. The online dictionaries have different ideas on it, but one interpretation is “severe tropical cyclone”.

matt v.

The monthly and annual AMO and PDO indices both started their decline after the 2005/2006 peak period as did the ACE curve above.

Pamela Gray

Douglas I hear ya! The usual trend is to go up in March. The current highs and lows are heading SOUTH! You gotta look at these Pendleton station graphs.

Steve Keohane

Interesting correlation with the loss of solar activity, less energy from the sun, less energy in cyclones. My understanding, poor as it may be, is that cyclones are fueled by high SST. Another indication that GW is not in Hansen’s ‘pipeline’.
Neil Jones (22:50:04), just checked the current side-by-sides on Cryosphere, their color scheme seems to be the same as a year ago. Interesting how they choose warm colors to mean greater ice.

Pamela Gray

re: the above graph page. The pull down menu allows you to change stations and will give you an idea of how regional this March weather is. You can see Jan, Feb, and Mar. You can also change to 2008 to compare. This year is WAY colder than last.


Re: Mike (04:16:59) :
If AGW causes hurricanes, what causes lack of hurricanes …?
One is “Climate”, the other is “Weather”?
kidding 🙂
I think the answer is AGW is irrelevant to both…

Steve Keohane

Neil Jones: They still are not showing anything from 2009 in the side-by-sides though. On the graph of extent for the NH, they are claiming less extent for 2009 vs. 2008.

Jon H

It’s Elvis and the space aliens. They are the ones doing all of this !!! George W Bush is their leader. He did blow up the levies in New Orleans, since they were designed to take a category 3 storm and were hit with only a Cat 5.
Sad thing is, I know several people who swear the CIA blew the levies in New Orleans to kill them. One of them still lives in the same house with a water mark 1m high on all walls, all over the house, a whole in the floor from damage, but they got the government checks to fix it. They got an Escalade and a Lexus coupe, plus a massive TV that cost more than $10,000. They are waiting for another check so they can get their daughter an Audi. Not fix the damage.
Drive around New Orleans now and you see lots of new cars, but not many homes that got fixed. Terrible site to see.

mark (20:16:31) :
i wonder if Gore will update his slideshows….
His most gracious Highness, Lord of the darkest and most noxious greenhouse gases, the Prince of the last remnants of frozen antartic territories, the One who was so clever as to stir up the deep slumber of sleeping consciousnes of the most despicable commons by teaching them with words of wisdom how to manage the world order, how not no breath, how not to dare farting, they and their so numerous cattle without paying previously to their Mighty Excellence a most convenient and liberating tax, the Prince of dark and filthy methane, will soon bless us with His Presence in the coming Summer season, to enlight us with truths uttered by His most admirable mouth, through words born deep in His always growing and magnificent belly His most wise sayings and new warnings referring to all the new calamities, we the commons have originated, and how He, as a punishment, has cleverly decided that, instead of warm, COLD will afflict us. This new era, so HE has decided, will bear HIS NAME to remind us WHO our Lord is and how we are suppose to behave before the ominous commandments He graciously pronounces, always for our wellbeing.

Len van Burgel

Re: westhoustongeo (04:37:57) :
I thought you would never ask! A thunderbox is an old aussie backyard dunny (lavatory). In the outback it wasn’t of the sturdiest construction.

Steve Keohane

Thought it would be interesting to compare ACE with solar activity. Using Oulu’s neutron count as an inverse proxy for solar activity, I took the neutron count for the same time period, inverted it and overlaid it on Ryan’s graph. There seems to be a few year’s lag between solar peaks and ACE peaks. If the correlation is causal we are in for a continuing plunge in ACE.