From the University of Hawaii at Manoa:
El Nino unusually active in the late 20th century
Spawning droughts, floods, and other weather disturbances world-wide, the El Niño – Southern Oscillation (ENSO) impacts the daily life of millions of people. During El Niño, Atlantic hurricane activity wanes and rainfall in Hawaii decreases while Pacific winter storms shift southward, elevating the risk of floods in California.
The ability to forecast how ENSO will respond to global warming thus matters greatly to society. Providing accurate predictions, though, is challenging because ENSO varies naturally over decades and centuries. Instrumental records are too short to determine whether any changes seen recently are simply natural or attributable to man-made greenhouse gases. Reconstructions of ENSO behavior are usually missing adequate records for the tropics where ENSO develops.
Help is now underway in the form of a tree-ring record reflecting ENSO activity over the past seven centuries. Tree-rings have been shown to be very good proxies for temperature and rainfall measurements. An international team of scientists spearheaded by Jinbao Li and Shang-Ping Xie, while working at the International Pacific Research Center, University of Hawaii at Manoa, has compiled 2,222 tree-ring chronologies of the past seven centuries from both the tropics and mid-latitudes in both hemispheres. Their work is published in the June 30, 2013 online issue of Nature Climate Change.
The inclusion of tropical tree-ring records enabled the team to generate an archive of ENSO activity of unprecedented accuracy, as attested by the close correspondence with records from equatorial Pacific corals and with an independent Northern Hemisphere temperature reconstruction that captures well-known teleconnection climate patterns.
These proxy records all indicate that ENSO was unusually active in the late 20th century compared to the past seven centuries, implying that this climate phenomenon is responding to ongoing global warming.
“In the year after a large tropical volcanic eruption, our record shows that the east-central tropical Pacific is unusually cool, followed by unusual warming one year later. Like greenhouse gases, volcanic aerosols perturb the Earth’s radiation balance. This supports the idea that the unusually high ENSO activity in the late 20th century is a footprint of global warming” explains lead author Jinbao Li.
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  IMAGE: Ancient trees, such as Polylepis tarapacana growing in rocky soils in the South American Altiplano, are sensitive to climate anomalies associated with large-scale climate patterns stemming from the El Niño-Southern…
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“Many climate models do not reflect the strong ENSO response to global warming that we found,” says co-author Shang-Ping Xie, meteorology professor at the International Pacific Research Center, University of Hawaii at Manoa and Roger Revelle Professor at Scripps Institution of Oceanography, University of California at San Diego. “This suggests that many models underestimate the sensitivity to radiative perturbations in greenhouse gases. Our results now provide a guide to improve the accuracy of climate models and their projections of future ENSO activity. If this trend of increasing ENSO activity continues, we expect to see more weather extremes such as floods and droughts.”
Citation: Li, J., S.-P. Xie, E. R. Cook, M. Morales, D. Christie, N. Johnson, F. Chen, R. D’Arrigo, A. Fowler, X. Gou, and K. Fang (2013): El Niño modulations over the past seven centuries. Nature Climate Change. http://dx.doi.org/10.1038/nclimate1936
This research was funded by the National Science Foundation, the National Basic Research Program of China (2012CB955600), the National Oceanic and Atmospheric Administration, the Japan Agency for Marine-Earth Science and Technology, FONDECYT (No.1120965), CONICYT/FONDAP/15110009, CONICET and IAI (CRN2047).
Further: I checked the Nature Climate Change web site and the paper is not there. In their paper they make this claim:
‘ “In the year after a large tropical volcanic eruption, our record shows that the east-central tropical Pacific is unusually cool, followed by unusual warming one year later. Like greenhouse gases, volcanic aerosols perturb the Earth’s radiation balance. This supports the idea that the unusually high ENSO activity in the late 20th century is a footprint of global warming” explains lead author Jinbao Li. ‘
This is the usual error made by climatists looking for a non-existent volcanic cooling. They find a La Nina valley and appropriate it for the volcano they think is cooling off the atmosphere. The warming that follows a La Nina is of course an El Nino. From that imaginary aerosol activity they jump over to to the idiotic conclusion that their imaginary increase of El Nino activity in the twentieth century represents a footprint of global warming. How does this kind of trash pass peer review?
Dr. Svalsgaard,
Thank you for taking the time to answer me, partially in your post above, and also by pointing me toward some helpful information. I believe I found the answer to my main question above (at 6:05PM) on page 19 of the paper whose link you provided above (at 8:02PM): http://www.leif.org/EOS/Causality-SSN-Climate.pdf..
Q. Re: Global Sea Level, why does it say “A recent acceleration?” on page 30 of that same paper, with an arrow toward the Global Sea Level around the year 2000? It didn’t look like an acceleration to a novice like me.
Re: the photo of John Moore and his porridge on p. 39 — looks like the photographer was threatening to give his breakfast to Goldilocks; John looked like he was saying, “Over my dead body.” heh, heh
Ah, well, I’m getting farther and farther off the topic.
Thanks again for answering. I hope you are enjoying your summer.
Your grateful student,
Janice
Funny how in the graph, during early times, without our C02 influx the earth naturally when beyond the dotted lines, {the boundary of natural variabililty!} so something unnatural was going on.
Janice Moore says:
July 1, 2013 at 10:09 pm
Q. Re: Global Sea Level, why does it say “A recent acceleration?” on page 30 of that same paper, with an arrow toward the Global Sea Level around the year 2000? It didn’t look like an acceleration to a novice like me.
Looks like there were three ‘accelerations’. the one on the right is the recent one, perhaps.
A recent paper says that ENSO cycles are predictable.
Ludescher, J., Gozolchiani, A., Bogachev, M.I., Bunde, A., Havlin, S., Schellnhuber, H.J. Improved El Niño forecasting by cooperativity detection. PNAS, 2013
“The new approach employs network analysis which is a cutting-edge methodology at the crossroads of physics and mathematics. Data from more than 200 measurement points in the Pacific, available from the 1950s on, were crucial for studying the interactions between distant sites that cooperate in bringing about the warming.”
Preumably the researchers used a neural network or a genetic algorithm. We can’t say much without knowing the algorithm. However, based on my own limited experience with neural networks, the models do not have a time dimension, thus the model would not detect a trend.
If prediction over time can be done precisely without a trend component, that implies the cyclical component swamps any trend.
Possibly the bottom line from this experiment is that, in relation to ENSO, no AGW effect is detectable.
frankpwhite says:
July 1, 2013 at 11:44 pm
A recent paper says that ENSO cycles are predictable.
Possibly the bottom line from this experiment is that, in relation to ENSO, no AGW effect is detectable.
By the same token, no solar effect can operate as otherwise the predictable ENSO could be used to predict the solar cycle. I guess the presumption is that the ENSO cycles are predictable because of their own inherent cycles.
frankpwhite says:
July 1, 2013 at 11:44 pm
A recent paper says that ENSO cycles are predictable.
The paper is here: http://arxiv.org/ftp/arxiv/papers/1304/1304.8039.pdf
“But the high solar activity in the middle of the 20th century does not fit well with the graph. So no solar connection.
Graph: http://www.leif.org/research/ENSO-and-SSN.png”
Right – but suppose you allow an ~60 year lag for the PDO cycle – you might have a decent correlation then – but yes it’s not the sun on it’s own that’s responsible.
frankpwhite says:
July 1, 2013 at 11:44 pm
A recent paper says that ENSO cycles are predictable.
Reading the paper reveals that they are not talking about ENSO cycles but using observations over the Pacific as a precursor to ENSO a year ahead.
BenG says:
July 2, 2013 at 12:18 am
Right – but suppose you allow an ~60 year lag for the PDO cycle – you might have a decent correlation then
And if you allow the lag to vary just right you might concoct a decent correlation [with anything]. But as Tweedledee said “‘if it was so, it might be; and if it were so, it would be; but as it isn’t, it ain’t”.
Cumulative Southern Oscillation Index (atmospheric pressure difference Darwin -Tahiti) shows strong correlation with geological data of the equatorial Pacific
http://www.vukcevic.talktalk.net/SOI.htm
except for the short period (1950s and early 60s) while nuclear atmospheric tests were conducted in the Pacific ocean.
Joseph Bastardi (July 1, 2013 at 8:00 pm)
“Cries of the eternal warm enso quickly fell by the wayside as soon as the PDO flipped…”
There was a slight lag as I tracked a lot of warm ENSO papers through about 2002-2003. There is a nice correlation between weather and models that predict that weather with about a five year lag.
RE: Bill Illis says:
July 1, 2013 at 4:07 pm
I also noticed they seemed to smooth-out or airbrush-out (or whatever) some mighty big El Ninos in the 1800’s.
Also the paper cherishes an implied belief everything was nice and stable in the past, however as I recall there was a pre-Inca civilization which was quite advanced, and had clever irrigation systems, that got wiped out by a prolonged drought. As I recall the drought lasted over fifty years, and could not have occurred unless El Ninos stopped altogether during that time. In other words “natural variability” has some wild swings.
What is special about the 20th century – the rising trend in ENSO variability in the tree-ring data started at least as early as 1600.
Climatologists seem to have a bipolar disorder regarding ENSO. Half the time they dismiss it as noise, questioning if it is a real phenomenon at all. The other half of the time, they come over all expert on ENSO and show how it proves AGW after all. Total BS merchants just making up BS as they go along.
If the tree-ring data is so good, then the sharp divergence between the blue and red lines in the graph indicate data manipulation in the instrumental record. Maybe the climate history editors decided that such a sharp temperature rise (~1900) and fall (~1940) was not credible so ironed it out with an adjustment.
“The dashed lines indicate boundary for natural variability. Recent El Niño behavior is largely beyond natural variability.”
Since El Niño behaviour is natural,they just need to move the dashed lines outwards. Unless they pre-suppose that the recent behaviour is not natural, in which case their conclusion is the same as their premise, which is circular reasoning.
What did I miss?
Leif Svalgaard says:
July 1, 2013 at 12:17 pm
tallbloke says:
July 1, 2013 at 12:05 pm
It’s the Sun stupid.
What a stupid claim. The Figure does not support that.
====
Well it does when compared to this one. The cumulative integral of your adjusted SSN series.
http://climategrog.wordpress.com/?attachment_id=410
Greg Goodman says:
July 2, 2013 at 4:47 pm
Well it does when compared to this one. The cumulative integral of your adjusted SSN
Hardly http://www.leif.org/research/ENSO-and-cum-SSN.png
And why should it compare with an integral over hundreds of years?
It’s just a quick exploration, not a definitive study. It would be better to convolve it with a decaying exponential maybe adjust the ‘neutral’ SSN a bit, but it follows the general ups and downs of their variability plot over 250 years. Since no one’s work out what drives ENSO yet , it looks like it merits a closer look.
Greg Goodman says:
July 2, 2013 at 5:41 pm
it looks like it merits a closer look.
We have the Wolf Numbers back to 1700, so let us integrate from there:
http://www.leif.org/research/ENSO-and-cum-SSN.png
I don’t think it is worthwhile chasing this.
The desperation continues to rise. Once ignored, nearly always taken out of trends to show CAGW CO2 effects, now Enso activity is being included perforce as part of the CO2 effect because this pesky index is such a big player in the temperature record’s rises and falls. Killing off phenomena that overwhelm CO2 is the only game in town among end-of-world climate sciencers since 1997 – knocking earth’s temp down from 15 to 14C for the 1930s to get rid of the dirty thirties temp pinnacle, leveling the various warming periods of the last 5000 years or so, going from CAGW to Climate Change to extreme weather events to weird weather as the temp record flattened since 1997, scuttling the 1922 all time global high of 136F in Libya in favor of 134 in Death Valley (July10, 1913) so that they have a chance of breaking a lower temp, putting a thermometer 20 miles away at Bad Water located in a natural topographic, westerly facing parabola next to an asphalt highway with a salt flat to the west to add a second sunshine to the site…..
milodonharlani says:
July 1, 2013 at 12:17 pm
http://www.sciencemag.org/content/339/6115/67.abstract#aff-1
Science 4 January 2013:
Vol. 339 no. 6115 pp. 67-70
DOI: 10.1126/science.1228246
Report: Highly Variable El Niño–Southern Oscillation Throughout the Holocene
This coral study is a useful reality check – going back 10 times further than the tree-ring study in time and finding current ENSO variability unexceptional. Clearly from the above figure only 6 cycles of variability is too few for any conclusions. I wonder if Cobb et al 2013 is cited in the above paper?
lsvalgaard says:
July 2, 2013 at 5:55 pm
Greg Goodman says:
July 2, 2013 at 5:41 pm
it looks like it merits a closer look.
We have the Wolf Numbers back to 1700, so let us integrate from there:
http://www.leif.org/research/ENSO-and-cum-SSN.png
I don’t think it is worthwhile chasing this.
Nice to see Leif has adopted my method of subtracting the mean SSN from the SSN and integrating the result as a proxy for OHC in making his comparison. The match is suggestive and definitely worth investigating further. It may have more to do with a solar effect on tree growth than ENSO, given the proxy used in the OP, but nonetheless demonstrates a clear Sun-climate link IMO.
tallbloke says:
July 3, 2013 at 2:51 am
Nice to see Leif has adopted my method of subtracting the mean SSN from the SSN and integrating the result as a proxy for OHC in making his comparison.
Nonsense, the Figure was in response to Greg’s use of the integral to show the clear lack of correlation.
Ask Greg where he got the technique from.
As for “The clear lack of correlation”, it’s a better correlation than the IPCC have for the link between co2 increase and temperature isn’t it?
tallbloke says:
July 3, 2013 at 12:35 pm
Ask Greg where he got the technique from.
This is a standard technique so don’t try to pretend otherwise.
As for “The clear lack of correlation”, it’s a better correlation than the IPCC have for the link between co2 increase and temperature isn’t it?
Pick any two random correlations, one will always be better than the other. That does not mean that any of them is any good. But, some people are more gullible than others. The easiest one to fool is yourself.