Excellent piece here from John McLean entitled ‘Ignoring a Natural Event to Blame Humans.’
In the last week of September 2007 we had yet another example of a well-recognized natural climate event being ignored in order to sell the notion that mankind is responsible for global warming. Maybe it was deliberate or maybe just ignorance, but you’d think that capable scientists would look closely at prior research and the data and not just be activists for their latest cause.
This time it was Power and Smith, from Australia’s CSIRO and Bureau of Meteorology respectively, who were reporting a weakened Walker Circulation over the last 30 years and a concurrent period of unprecedented El Niño dominance [note 1], both of which they blamed on human activity.
Last year in May it was Vecchi et al [2] who told us that the same Walker Circulation had weakened by 3.5% since the mid-1800s and there that there was a just 1% probability that this was due to natural events. Vecchi and Soden [3] recently continued their line of argument from 2006 by claiming that an ensemble of 23 climate models confirms that weakening of the Walker Circulation is to be expected under anthropogenic warming.
These three papers seem to be the product of researchers lost in their computer simulations and putting the virtual reality of computer models ahead of observational reality.
What they attribute to human activity are natural events that have been well described by other researchers.
Read the full article.
There is also a follow up article by Joseph D’Aleo enitled ‘More on The Great Pacific Climate Shift and the Relationship of Oceans to Temperatures and Arctic Ice’
In a recent guest blog, John McLean explained how Australia’s CSIRO and Bureau of Meteorology (Power and Smith) respectively were reporting a period of unprecedented El Niño dominance the last 30 years, which they blamed on human activity. Last year in May it was Vecchi who told us there was a just 1% probability that this was due to natural events.
On The Weather Channel blogs, meteorologist Stu Ostro, also found a similar continuity shift in weather pattern starting 30 years ago. Blog comments back to Stu and John McLean’s blog here showed how the change had precious little to do with anthropogenic factors but was a large scale cyclical climate shift known for decades as the Great Pacific Climate Shift.
Later on it was shown to be the latest change in a cyclical regime change given the name Pacific Decadal Oscillation by Mantua et al. This followed research showing decadal like ENSO variability by Zhang et al. in 1993.
They found the Pacific Ocean temperature regime and overlying pressure patterns tended to persist in one mode for two or three decades and then flip to very nearly the opposite mode for a similar period.
Read more.
3 relevant papers:
GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L06712, doi:10.1029/2005GL025052, 2006
Long-term behaviour of ENSO: Interactions with the PDO over the past 400 years inferred from paleoclimate records
Danielle C. Verdon1 and Stewart W. Franks1
[1] This study uses proxy climate records derived from paleoclimate data to investigate the long-term behaviour of
the Pacific Decadal Oscillation (PDO) and the El Nin˜o Southern Oscillation (ENSO). During the past 400 years,
climate shifts associated with changes in the PDO are shown to have occurred with a similar frequency to those
documented in the 20th Century. Importantly, phase changes in the PDO have a propensity to coincide with
changes in the relative frequency of ENSO events, where the positive phase of the PDO is associated with an
enhanced frequency of El Nin˜o events, while the negative phase is shown to be more favourable for the development of La Nin˜a events.
HYDROLOGICAL PROCESSES INVITED COMMENTARY Hydrol. Process. 16, 559–564 (2002) DOI: 10.1002/hyp.600
Assessing hydrological change: deterministic general circulation models or spurious solar correlation?
Stewart W. Franks Centre for Environmental Dynamics, University of Newcastle, Callaghan 2308, New South Wales, Australia
Atmospheric greenhouse gas concentrations are at an historic high, and this must lead to strong concerns over our future climate. However, it is not often appreciated that solar activity is also at an historic high [from 400 years of solar observations (Hoyt and Schatten, 1997)]. The problem of disaggregating these factors in temperature trends is largely due to long-term upward trends of both factors. However, through the use of a simple non-linear ARX[1] model, it has been shown that temperature trends over the 20th century display some coherence with solar irradiance. It should therefore be considered that documented hydrological changes in regional climates, available via the IPO/PDO indices, may be driven by solar–terrestrial interactions. Until GCMs can elucidate the mechanisms of hydrological variability, then any projections of long-term future climate changes must be viewed with obvious caution.
GEOPHYSICAL RESEARCH LETTERS, VOL. 30, NO. 2, 1035, doi:10.1029/2002GL015992, 2003
Multi-decadal variability of flood risk
Anthony S. Kiem, Stewart W. Franks, and George Kuczera School of Engineering, University of Newcastle, Callaghan, New South Wales, Australia
[1] Recent research has highlighted the persistence of multi-decadal epochs of enhanced/reduced flood risk across
New South Wales (NSW), Australia. Recent climatological studies have also revealed multi-decadal variability in the
modulation of the magnitude of El Nin˜o/Southern Oscillation (ENSO) impacts. In this paper, the variability of flood risk
across NSW is analysed with respect to the observed modulation of ENSO event magnitude. This is achieved
through the use of a simple index of regional flood risk. The results indicate that cold ENSO events (La Nin˜a) are the
dominant drivers of elevated flood risk. An analysis of multidecadal modulation of flood risk is achieved using the interdecadal Pacific Oscillation (IPO) index. The analysis reveals that IPO modulation of ENSO events leads to multi-decadal epochs of elevated flood risk, however this modulation appears to affect not only the magnitude of individual ENSO events, but also the frequency of their occurrence. This dual modulation of ENSO processes has the effect of reducing and elevating flood risk on multi-decadal timescales. These results have marked implications for achieving robust flood frequency analysis as well as providing a strong example of the role of natural climate variability.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
He is an interesting and entertaining speaker, is our Stewart W. Franks.
No evidence of a “weakened (Luke ) Walker Circulation ” on this blog!
I’ve got some problems with John Maclean’s piece.
Firstly.THe Great Pacific Climate Shift of 1976 cannot be proven to not have an anthropogenic global warming causative component.
Secondly,Maclean claims the three papers “..claim that anthropogenic global warming drives the Southern Oscillation..” Drives or is influencing? “,but it is widely accepted that a very strong El Nino caused the 1998 temperature spike.” Indeed it is widely accepted, and why the “but” in relation to the first part of the sentence? Maclean then writes “Taken together these comments imply a double-feedback mechanism with warming causing El Nino events and El Nino causing warming. If this was correct then surely at some point in the Earth’s last 4 billion years such runaway conditions would have already occurred and rendered this planet uninhabitable.” Surely he can’t be suggesting that ENSO has a verifiable 4 billion year history? Ever heard of continental drift? And why would a runaway El Nino make the entire planet uninhabitable?
Yes yes yes – Old news for Scott Power
Inter-decadal modulation of the impact of ENSO on Australia
Journal Climate Dynamics
Issue Volume 15, Number 5 / May, 1999
Authors
S. Power1, T. Casey1, C. Folland2, A. Colman2, V. Mehta3
1Bureau of Meteorology Research Centre, Melbourne, Australia
2Hadley Centre for Climate Prediction and Research, Meteorological Office, Bracknell, Berkshire, UK
3Joint Center for Earth System Science, University of Maryland/NASA Goddard Space Flight Center, MD, USA
Abstract
The success of an ENSO-based statistical rainfall prediction scheme and the influence of ENSO on Australia are shown to vary in association with a coherent, inter-decadal oscillation in surface temperature over the Pacific Ocean. When this Inter-decadal Pacific Oscillation (IPO) raises temperatures in the tropical Pacific Ocean, there is no robust relationship between year-to-year Australian climate variations and ENSO. When the IPO lowers temperature in the same region, on the other hand, year-to-year ENSO variability is closely associated with year-to-year variability in rainfall, surface temperature, river flow and the domestic wheat crop yield. The contrast in ENSO’s influence between the two phases of the IPO is quite remarkable. This highlights exciting new avenues for obtaining improved climate predictions.
John McLean has pointed out that “Joe’s only sort of correct in his latest piece because the change in the Southern Oscillation occurred before the change in PDO, at least it does according to my method of identifying the turning point.”
Of course may it doesn’t even exist – an artifact perhaps? Red noise?
Journal of Climate
Volume 18, Issue 1 (January 2005)
Rainfall Variability at Decadal and Longer Time Scales: Signal or Noise?
Holger Meinke, Peter deVoil, Graeme L. Hammer, Roger C. Stone, and Andries Potgieter
ABSTRACT
Rainfall variability occurs over a wide range of temporal scales. Knowledge and understanding of such variability can lead to improved risk management practices in agricultural and other industries. Analyses of temporal patterns in 100 yr of observed monthly global sea surface temperature and sea level pressure data show that the single most important cause of explainable, terrestrial rainfall variability resides within the El Niño–Southern Oscillation (ENSO) frequency domain (2.5–8.0 yr), followed by a slightly weaker but highly significant decadal signal (9–13 yr), with some evidence of lesser but significant rainfall variability at interdecadal time scales (15–18 yr). Most of the rainfall variability significantly linked to frequencies lower than ENSO occurs in the Australasian region, with smaller effects in North and South America, central and southern Africa, and western Europe. While low-frequency (LF) signals at a decadal frequency are dominant, the variability evident was ENSO-like in all the frequency domains considered. The extent to which such LF variability is (i) predictable and (ii) either part of the overall ENSO variability or caused by independent processes remains an as yet unanswered question. Further progress can only be made through mechanistic studies using a variety of models.
And ponder perhaps:
The existence of decadal teleconnection patterns in low pass filtered records does not imply decadal predictability
The existence of decadal signals in low pass filtered records does not imply decadal predictability.
http://iprc.soest.hawaii.edu/~axel/AMO/Power.ppt
Unfortunately for Luke I sometimes tend to check his references and in this case I did.
Let me quote an article just published in the latest edition of New Concepts in Global Tectonics Newsletter, a peer reviewed publication:
“The possibility of a connection between seismicity and heat waves/bushfires arises from several sources. Over ten years ago, a small note in the Australian Geologist outlined a close association between the onset of El Nino and increased seismicity in the East Pacific. This was taken from work by D. A. Walker who has since (1995) confirmed the nexus, so it appears that earthquake swarms in the Easter Island region are able to heat the ocean sufficiently to halt the Humbolt current, hence an El Nino. In the December 2006 issue of NCGT Newsletter, Ismail Bhat also brought attention to the relationship between earthquake swarms and the bottom heating of oceans, in particular the Adriatic Sea and its bearing on the 2003 European heatwave. In a somewhat earlier NCGT issue – which I am unable to quote at the moment – a passing mention was also made of the idea that the fierce forest fires of California might be exacerbated by the release of methane from the ground”. (c.f. Earthquake Activity and Bushfires – Is there a connection, P.M James, NCGT Newsletter 44, September 2007, pp 47-50).
None of these geological facts are incorporated in any GCM, let alone considered by climate scientists.
However solar cycles are predictable, based on the observed 22 and 11 year ones. As the earth and sun are linked electromagnetically, then it may be possible to discern a predictable forecase at these cycles. Note that solar cycles are not decadal but 11-3 years of duration. Decadal patterns is simply mathematical laziness – makes for easy computer simulation.
The power point presentation that Luke refers to, and from his pithy comments, note “decadal” patterns. 11 years is not a decadal pattern – 10 years is. It’s a 10% discrepancy that becomes signficant the longer one projects. Or is it forecasting?
Correction before I get flailed by the usual suspects: it’s 11-13 years of duration.
Well instead of publishing hearsay and speculation in “newsletters” – yechy – why not try to get published somewhere serious and we’ll see what they’ve really got. You realise beer consumption in Japan is correlated with the SOI Louis.
decadal
On the time scale of decades, or tens of years.
Climate scientists everywhere apologise for corruption of the Engalesh as they are also for multi-decadal but not centennial or millenial.
Louis what do you reckon though – is the IPO red noise or what?
“All three papers suggest that either the authors have an appalling lack of knowledge about one of the most important climate shifts in the twentieth century or that this event was deliberately ignored in order to falsely support the claim of man-made warming. There are no other options. I’d like to think it was the former, but there’s plenty of reasons to consider it may have been the latter.”
There’s nothing like a conspiracy theory to get the blood pumping.
“Excellent piece here from John McLean entitled ‘Ignoring a Natural Event to Blame Humans.'”
The converse is also exactly true and sums up AGW skeptics:
‘Ignoring Human Activity to Blame Natural Events’
All in all it is AGW skeptics that are doing the most ignoring as the overwhelming body of scientific evidence points to THIS particular warming event, happening now, is anthropogenic.
My garden is having the wettest spring since records began (er, two years ago). There are 31 mm of rain in the gauge from the last 48 hours. A gauge nearby has 75 mm. The BoM gauge in Perth reports only 10 mm. It must be leaking.
The reason for this rain is that as Australia drifts north, periodic seismic disturbances cause exposure of hot rocks or magma on the ocean floor around Indonesia. These cause bodies of warm water, which in turn cause ENSO and the Indian Ocean Dipole, and the Walker Circulation, and the Hadley Cells. These all affect Australian climate. I don’t need any references. My garden gnome told me. I believe my gnome more than I do the ABC. He is less kitsch, and doesn’t keep showing me power station cooling towers. Scientific studies in universities have shown that he has only a 1% probability of error, by the Central Limit Theorem and Chebyshev Inequality (Fludworthy et al. 2007).
Davey
Have you seen these?
http://environment.newscientist.com/article/dn12218-thousand-of-new-volcanoes-revealed-beneath-the-waves.html
I think this is the article referenced…
http://www.esc.cam.ac.uk/esp/resources/publications/publications/Hillier2007b.pdf
Thanks for the references, Arnost. I don’t think anyone can accuse Hillier and Watts of slapdashery. Joking apart, I really do believe there is much in the idea that ocean warming is more likely a result of tectonics than anything else. This does not rule out extra-terrestrial and atmospheric causes, but it puts them in a more mature perspective. I am having some fun with a reference to the Anglican Common Book of Prayer (1622) which says “Give us grace, that, being not like children carried away with every blast of vain doctrine, we may be established in the truth of thy holy Gospel.”
P.S. I have passed the references on to my garden gnome.
I think that one day this sub-SST warming thing will have legs…
For example, we have what looks to be a very strong La Nina SST wise but a nothing SOI. (Did you know last month Nino1&2 ave temp was at a record (since 1950 anyway) low? 18C at the equator – BRRRR.) And we have a cool Northern Aust tropics.
Well consider… we had that biggish earthquake in Dec 2004. A lot of pent up stress released (plus barocline mixing). Less stress on the tectonic plates, less heat and probably less undersea volcanic fumarole activity. Suprise surprise – unseasonally cool SSTs.
My gnome may want to contact your gnome one day and do a paper…
I find ENSO fascinating and the points made by McLean most interesting. It’s amazing how the cumulative annual mean SOI hovered around zero in the early 1900’s before climbing rapidly until 1976. Since then it has fallen rapidly, and our rainfall with it.
Here’s the abstract from an interesting paper published in Nature that gives a little insight into the ancient cycles of ENSO:
Variability of El Niño/Southern Oscillation activity at millennial timescales during the Holocene epoch
Christopher M. Moy, Geoffrey O. Seltzer, Donald T. Rodbell and David M. Anderson
Nature 420, 162-165 (14 November 2002)
The variability of El Niño/Southern Oscillation (ENSO) during the Holocene epoch, in particular on millennial timescales, is poorly understood. Palaeoclimate studies have documented ENSO variability for selected intervals in the Holocene, but most records are either too short or insufficiently resolved to investigate variability on millennial scales1, 2, 3. Here we present a record of sedimentation in Laguna Pallcacocha, southern Ecuador, which is strongly influenced by ENSO variability, and covers the past 12,000 years continuously. We find that changes on a timescale of 2–8 years, which we attribute to warm ENSO events, become more frequent over the Holocene until about 1,200 years ago, and then decline towards the present. Periods of relatively high and low ENSO activity, alternating at a timescale of about 2,000 years, are superimposed on this long-term trend. We attribute the long-term trend to orbitally induced changes in insolation, and suggest internal ENSO dynamics as a possible cause of the millennial variability. However, the millennial oscillation will need to be confirmed in other ENSO proxy records.
Davey, Here’s one more…
This is the last weekly report from the Polastern which just spent a bit of time in the Arctic doing bits and pieces of very interesting research. See the first paragraph.
http://www.awi.de/en/infrastructure/ships/polarstern/weekly_reports/all_expeditions/ark_xxii/ark_xxii2/24_september_2007/
Davey
if the warming is due to tectonics, then does that rule out solar radiation? If it does, then why is Mars warming?
Thanks Arnost,
My gnome says he wants his name first on the paper, in Nature, of course.
SJT,
No, if you read carefully you will see that I say there are other possibilities beside tectonics. These include extra-terrestrial (solar) and AGW (atmosphere). I just ask for multiple hypotheses, not one vain blast of doctrine, and abusive contempt for all others.
I don’t know why Mars is warming. Does it have a molten core? Any ideas?
Davey and Arnost
I have a couple of goats in the back paddock who will do the peer review–anonymously of course.
And a few roos loose in the top paddock too.
Davey it’s well known that Gnome production in well correlated with the SOI. Demand is not though – figure that out.
Ah, I see the vexatious bloggerant is at it again.
Multiple posts on multiple threads all saying prescious little, the sole purpose of which is to assuage a mental disorder in the auther.
Yes I agree Mally poos – tell Davey to keep on topic !
Hah!
I heard a dirty rumor that Mars is heating up due to “magic” dust. This magic dust gets blown around and when it lands it “knows” just how to fall so as to avoid the darkish patches of Mars.
It’s a miracle.
People should remember that the PDO wasn’t really codified until the 1990s, even though many people had ideas that Pacific SSTs influenced climate worldwide.
The Great Climate Shift of 1976 was a change in mode of the PDO from negative to positive. The PDO appears to oscillate every 30-45 years. During negative years, the El Nino events are weak and sporadic. La Nina events appear to dominate. During the positive phase of the PDO, El Nino events are enhanced, and come every 4-7 years.
Once can also chart global average temps for the last 100 or so years and see that they mirror changes in the PDO. Generally global temps increase when the PDO is in a postive phase, and decrease when the PDO is in a negative phase. Other teleconnections do not have the kind of global reach that the PDO has. The NAO and AMO appear to be more regional.