Connecting ENSO, PDV, and the North and South Pacific

A new paper in Geophysical Research Letters was brought to my attention by Dr. Leif  Svalgaard.

Tropical origins of North and South Pacific decadal variability by Jeremy D. Shakun and Jeffrey Shaman makes some very interesting findings suggesting that both the northern and southern Pacific Ocean has evidence of the Pacific Decadal Variation PDV being driven by ENSO variations. They produced a model, which when run correlates reasonably well with observations.

PDV_Model_observered
Fig 4. Observed (red line with circles) and modeled (blue line with slashes) PC1s for the (top) North and (bottom) South Pacific. The model is of an AR-1 process forced by ENSO, see the paper for details - click for a larger image

Abstract:

The origin of the Pacific Decadal Oscillation (PDO), the leading mode of sea surface temperature variability for the North Pacific, is a matter of considerable debate. One paradigm views the PDO as an independent mode centered in the North Pacific, while another regards it as a largely reddened response to El Nin˜o-Southern Oscillation (ENSO) forcing from the tropics. We calculate the Southern Hemisphere equivalent of the PDO index based on the leading mode of sea surface temperature variability for the South Pacific and find that it adequately explains the spatial structure of the PDO in the North Pacific. A first-order autoregressive model forced by ENSO is used to reproduce the observed PDO indices in the North and South Pacific. These results highlight the strong similarity in Pacific decadal variability on either side of the equator and suggest it may best be viewed as a reddened response to ENSO.

They write about the graph above:

…we model PDV as a first-order autoregressive process driven by ENSO as done by Newman et al. [2003]. This AR-1 model is applied to the North and South Pacific separately.

Shakun-Shaman_AR1_model

The modeled PDO index at year n is a function of the modeled PDO index at n – 1 and the observed ENSO index (Nino 3.4) at n. These annually-averaged indices are centered on boreal winter (Jul–Jun) for the North Pacific and austral winter (Jan–Dec) for the South Pacific. Per Newman et al. [2003], the coefficients β and α are parameters derived, respectively, by regression of the PDO index on the ENSO index, then autoregression of the residual time series with a lag of one year. h is an uncorrelated noise term not used in our analysis but shown for completeness. a and b are 0.51 and 0.56 for North Pacific PC1 and 0.62 and 0.71 for South Pacific PC1. While Newman et al. [2003] found this simple model did a remarkable job reproducing the observed 20th century PDO index in the North Pacific (r = 0.63 in our study), it yields an even stronger fit to our Southern Hemisphere PDO index (r = 0.71) (Figure 4).

The greater success of the model in the South Pacific may be a function of its larger α and β terms, which indicate that the persistence of SST anomalies and ENSO forcing are more important. The stronger ENSO signal in the South Pacific may derive from the equatorial asymmetry of ENSO SST anomalies in the eastern tropical Pacific, which extend considerably farther to the south than to the north. One implication of this finding is that the South Pacific may be a better place to develop paleo-ENSO records as it appears to contain a ‘cleaner’ ENSO signal.

Conclusion

Deriving a Southern Hemisphere equivalent of the PDO index shows that the spatial signature of the PDO can be well explained by the leading mode of SST variability for the South Pacific. Thus, PDV appears to be a basin-wide phenomenon most likely driven from the tropics. Moreover, while it was already known PDV north of the equator could be adequately modeled as a reddened response to ENSO, our results indicate this is true to an even greater extent in the South Pacific.

Leif has a copy of the paper on his website that you can read here

Citation:

Shakun, J. D., and J. Shaman (2009), Tropical origins of North and South Pacific decadal variability, Geophys. Res. Lett., 36, L19711, doi:10.1029/2009GL040313.

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APE
October 16, 2009 11:23 pm

Small typo in your summary section “evidence”
REPLY: fixed, thanks – A

crosspatch
October 17, 2009 12:03 am

I find the divergence between observation and model in the final few years interesting.

October 17, 2009 12:10 am

Sun inputs energy, it creates clouds and winds, they drive ocean cycles and oceans drive the climate. Have I understood it right?

tokyoboy
October 17, 2009 12:19 am

Most of the heat on the earth’s surface comes from the sun, and its intensity has been almost constant in these 100 plus years (except for a 0.1%-level fluctuation during a solar cycle).
In view of this, I now suspect, as a chemist not familiar enough with this field, that PDO, PDV, AMO etc. are caused by periodic changes of heat partitioning between the surface and underneath of the ocean, and this in turn is caused by the periodic pattern change of ocean currents (and ultimately by the periodic pattern change in the wind?).
Correct me please if such a speculation is wrong.

rbateman
October 17, 2009 12:40 am

Yes, it does diverge the last 8-9 years in both hemispheres, but the N. Pacific diverged around 1933-4 oppositely and not in concert with the South.
1910 also diverges, though briefly and more shallow.
Looks like the data is current to 2007.
How are we doing today?

October 17, 2009 12:44 am

Tokyoboy, even the sun irradiation was almost constant, fluctuation in cloud cover (earth albedo) would regulate the amount of energy being absorbed in the oceans.
Concerning your thought about oceanic cycles, me as a chemist have similar view as well 🙂

tallbloke
October 17, 2009 1:18 am

The north and south Pacific’s temperature variations are strongly affected by the warmer equatorial waters spreading out from where the sun shines down most directly all year round.
Whodathunkit?

Paul Vaughan
October 17, 2009 3:06 am

This “reemergence” theory is a lazy construct, but Figure 1 offers loud hints…

Kate
October 17, 2009 3:25 am

An item appeared about this today in The Telegraph
http://www.telegraph.co.uk/earth/earthcomment/geoffrey-lean/6349529/Sceptics-figures-on-global-warming-simply-dont-add-up.html
Where Geoffrey Lean asserts that:
“Almost all climatologists expect warming to continue in the long term, but – because of natural fluctuations – they disagree about the immediate future. Part of the conclusion of one paper – “global surface temperatures may not increase over the next decade…” – is often cited by the sceptics. They rarely quote the rest of sentence “…as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming”.
You may wish to comment on that statement in the box provided on his page.

Terry
October 17, 2009 3:27 am

It is nice to see that even though complex physical models tend to be the flavour of the day in some circles, reduction to more simple models often holds the key. Or at least are consistent with observations. I always believe that most systems can be reduced to simple models, and if they cant then the model is wrong.

October 17, 2009 3:54 am

Hmm. Now all they have to do is get their models to simulate the following effect. During significant traditional El Nino events, warm waters travel from the Pacific Warm Pool to the eastern tropical Pacific. The Coriolis effect draws some of that eastbound warm water into the extratropics of the North and South Pacific where it circulates and returns to the tropics a few years later to form El Nino Modoki.

October 17, 2009 3:55 am

Thanks for the heads-up, Leif.

Editor
October 17, 2009 4:01 am

The main influences on the ENSO seems to be the amount of solar radiation reaching sea surface in the southeast pacific. This is controlled largely by amount of cloud cover, aerosols, and particulates. The volcanoes in the area have thus a very significant input into global climate beyond volcanoes in other regions of the world.
Another major input is the turbidity of the water in the area, which is affected by both storms and runoff, as well as upwellings, plankton blooms, etc. Turbidity impacts the amount of solar energy absorbed and to what depth…

October 17, 2009 4:05 am

I like their use of a low pass filter to highlight the low frequency component of the SST anomalies in Figure 1.
I have a hunch that a lot of the so called “secular” climate trends would vanish in a puff of Fourier Transform, if the time series were broken down into meaningful frequency components.
Thanks to Dr. Svalgaard for spotting this paper.

Mark Fawcett
October 17, 2009 4:21 am

OT – Holy global-warming batman, the BBC (news.bbc.co.uk/2/hi/south_asia/8311838.stm) has just shown footage of the Maldives’ cabinet meeting underwater, to sign a request to “the rest of the world” to reduce CO2 concentrations to “safe” levels.
Odd, how no mention is made of [a] the fact that global sea-levels ain’t doing much, [b] enviro-mentalists had previously ripped up an old tree to try to hide the fact that sea-levels local to the Maldives had been falling and [c] coral atolls should, in fact, be immune to gradual sea-level rise as they in fact grow upwards as sea-level rises.
I really, really, think I may be living in an alternate reality…
Cheers
Mark

GP
October 17, 2009 4:29 am

From the report:
“These annually-averaged indices are centered on boreal winter (Jul–Jun) for the North Pacific and austral winter (Jan–Dec) for the South Pacific.”
Is that correct for ‘winter’? It seems counter intuitive.

steven
October 17, 2009 5:04 am

“Most of the heat on the earth’s surface comes from the sun, and its intensity has been almost constant in these 100 plus years (except for a 0.1%-level fluctuation during a solar cycle).”
There is the Wilson and Mordvinov study which indicated a possible long term trend towards increasing TSI amounting to about a 0.05% increase per decade. Geophysical Research Letters Vol 30 No 5 2003

Tenuc
October 17, 2009 5:08 am

Interesting stuff. Surprising that the model drifts away from reality over the last few years, and is trending much cooler. Perhaps something else not captured by the model is driving events – reduced insolation perhaps?

J.Hansford
October 17, 2009 5:58 am

Kate (03:25:44) :
An item appeared about this today in The Telegraph
http://www.telegraph.co.uk/earth/earthcomment/geoffrey-lean/6349529/Sceptics-figures-on-global-warming-simply-dont-add-up.html
Where Geoffrey Lean asserts that:
“Almost all climatologists expect warming to continue in the long term, but – because of natural fluctuations – they disagree about the immediate future. Part of the conclusion of one paper – “global surface temperatures may not increase over the next decade…” – is often cited by the sceptics. They rarely quote the rest of sentence “…as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming”.
You may wish to comment on that statement in the box provided on his page.
………………………………………………………………………………………………………
Kate, what anthropogenic warming?… as far as anyone can tell, the observations are of Natural climate conditions in their entirety…. There are no observations of Anthropogenic warming, merely a hypothesis and some models based on flawed data from bristle-cone pines and Siberian spruce tree rings.
CO2 and Temperature have diverged in the modern satellite record as they did from 1940 to 1979 in the thermometer record. Ice cores going back tens of thousands of years in time, show CO2 lagging Temperature…..
So I ask again…….. What Anthropogenic Global Warming?
(I assume this is the box I was supposed to use for my statement, yes?: )

Pascvaks
October 17, 2009 6:03 am

If anyone already has graphed the “difference” between Observed and Modeled for NP and SP since 1900, please post it. Assuming the observed and model data are both quite accurate, the devil would seem to be in the +/- of the difference.

October 17, 2009 6:19 am

Tenuc (05:08:55) : said
“Interesting stuff. Surprising that the model drifts away from reality over the last few years, and is trending much cooler. Perhaps something else not captured by the model is driving events – reduced insolation perhaps?”
And possibly increased albedo, cloud cover. Science has a lot of work to to and I recall seeing an earlier IPCC chart showing “low confidence” in many areas of climatology, yet they were very confident in their summary.
Also I an curious about the difference in how 70% of our planet, the oceans, aborb LW radiation vs SW radiation. I understand the energy from SW radiation penetrates far deeper into the ocean surface, and is therefore held within the planets heat budged far longer then LW radiation. Is it possible that some of this energy gets trapped in a thermocline and actually moves into the deep ocean?
The possible combination of short term insolation affects to changes in albedo / cloud cover, and therefore almost instant astmosphere heat content, and long term changes in ocean heat content due to the long term ocean absorbtion from increased solar insolation due to the same changes in albedo cloud cover, appears to open the possbility of dramatic effect both short term and long term from solar changes having very little to do with TSI changes, and everythin to do with clouds.
Am I understanding this correctly, and how well is this being studied?
Thanks in advance for any response.

Kate
October 17, 2009 6:33 am

” So I ask again…….. What Anthropogenic Global Warming?
(I assume this is the box I was supposed to use for my statement, yes?: )”
…There is no detectable warming. The box to state your views are on the page of the originating article that I quoted:
http://www.telegraph.co.uk/earth/earthcomment/geoffrey-lean/6349529/Sceptics-figures-on-global-warming-simply-dont-add-up.html
Hope that clears things up.

Robert Wood
October 17, 2009 7:22 am

tokyoboy, the Sun’s output may have not varied much, but albedo doesn’t need to vary much to greatly change the amount arriving on the oceans.

Sean
October 17, 2009 7:22 am

I find if very interesting that Leif, WUWT’s solar expert in chief, is reading the ocean circultion literature so closely.

October 17, 2009 7:31 am

So, are events in the air causing the ocean cycles or are events in the oceans causing change in the air circulations ?
Are there any independent ocean cycles imposing their will on the air or are they all products of changes that occur in the air first. A pretty critical issue as regards the plausibility of both the warmist viewpoint and a number of air based sceptical viewpoints such as that of Svensmark and that of our own Erl Happ.
As far as I can see the changes in the air always follow the changes in the sea surface temperatures.

Clive
October 17, 2009 7:33 am

Thanks for the interesting paper … as a casual observer, it is indeed complex but it seems to reaffirm that “it is the sun stupid” and, of course, the oceans.
(May have mentioned this previously… it is my little way of feeling insignificant RE: GW.)
There are ~ 250,000,000 tonnes of ocean water for every person on earth. (The math is ~ correct.)
I just can’t see a family of four in their suburban bungalow; SUV and compact car; their jobs at the factory and school; all of their trappings having any affect whatsoever on ocean temps (on “their” one billion tonnes of water) compared to the sun beating down (or not) on the oceans somewhere on earth 24/7.
“Warmers” apparently think we are relatively important. We are nothing.
Clive
In the not-quite-so-frozen-North … not like last week anyway ☺

anna v
October 17, 2009 7:47 am

I am always bemused by these ocean discussions, particularly as they never mention/model the tides.
Twice a day a big bulge of energy travels around the globe and moves waters from the bottom up . It moves the land too , but that is another story.
Is it possible that this motion plays no role in distributing the heat of the ocean? It cannot all be vertical, from conservation of angular momentum.Even the vertical disturbance will mix cold and hot waters to some extent.
Considering also that there are high tides and low tides and “some other name” tides due to the variable orbit of the moon about the earth, I could easily see time modulations due to that.
Does anybody know ( have a link) whether tideshave been modeled/calculated or whether they are ignored because the effect is much smaller that the other drivers of ocean currents?

JeffK
October 17, 2009 8:09 am

@ GP:
-From the report:

-“These annually-averaged indices are centered on boreal winter (Jul–Jun) for the North Pacific and austral winter (Jan–Dec) for the South Pacific.”

-Is that correct for ‘winter’? It seems counter intuitive.
No, the statement is correct. Notice, the indicies are *centered* on the repective winters which means the time spans need to start/end in the respective summers so the winter times would be in the center of the timespan.
Jeff

Phil Cartier
October 17, 2009 8:20 am

I really wish that all these climate modelers would come up with a model that works from first principles, not just by twiddling with recorded data. Take a look at the work Einstein did on the phote-electric effect. He figured out what had to be at the basis of the effect and worked out a simple equation that has withstood the test of time, and had significant implications that were proved true well after he developed the equation.
When the climate modelers can show me a set of equations of similar insight and economy that do not depend of “parameters” elicited from previous data I might believe them. Then, when they can take the climate data from any historic period, show that the model accurately predicts the data from the starting conditions, and works throughout the data set, then they will have a model that MAY usefully predict future climate trends.
The model used in this discussion is an empirical model, based on parameters derived from the historical data. One of the first things I learned in statistics is that an empirical model only works within in the data range used to develop the parameters. So, the fact that the model and data diverge at some point IS TO BE EXPECTED. It is simple curve fitting, which can tell us something about the trends and variation in the data, but says absolutely nothing about the underlying physics or mechanisms.
As the inimitable Yogi Berra said, “making predictions is very tough, especially about the future”. I like to add my own corollary, ” it’s even harder when you want the right answer”.

gtrip
October 17, 2009 8:26 am

As a weather observer in Colorado Springs in the late 80’s, I witnessed an Aurora one early morning (first observation had to be done at 3:55 am). Was it possible that I witnessed the beginning of the 90’s global warming that has caused so much concern with our society?

October 17, 2009 8:42 am

The cold dark deep of the oceans is not aware of your tides, Anna. What are they? They are a constant redistribution of the ocean’s superficial layers, with minimal heat redistribution. A high tide only occurs on a full moon. ( to the sun the moon is always full except when the Earth gets in the way)
Tsunamis on the other hand involve deeper disturbances in the ocean’s energy. Tsunamis are caused by anthropogenic global warming.

commieBob
October 17, 2009 9:17 am

Slightly O/T:
I wonder if we’ve reached some kind of tipping point where we get an avalanche of major media stories doubting AWG. This morning there is an opinion piece in the Globe and Mail by Rex Murphy. Rex’s opinion is that the leader of the Liberal party (Michael Ignatief) should not tie himself to the AWG bandwagon. We’ll see if Ignatief takes the advice or not but it is reasonably certain that he (scholar that he is) will give it due consideration.
The thing that I find heartening is that Rex (love him or hate him or both at the same time) is writing in ‘Canada’s National Newspaper’ and, in a sense, what we are hearing is the voice of the establishment.
http://www.theglobeandmail.com/news/opinions/michael-ignatieff-should-think-outside-the-green-box/article1327161/

Michael
October 17, 2009 9:25 am

Stream of Conscience: Not Evil Just Wrong to Stream Live, for Free, Over Internet This Sunday
http://www.reuters.com/article/pressRelease/idUS172412+16-Oct-2009+PRN20091016

Michael
October 17, 2009 9:32 am

Superfreakonomics: Global Cooling, Patriotic Prostitutes and Why Suicide Bombers Should Buy Life Insurance
http://www.ft.com/cms/s/2/1c1d0386-b9e4-11de-a747-00144feab49a.html

Cap'n Rusty
October 17, 2009 9:39 am

Clive:
The “tonnes of ocean water per person” ratio creates a mental picture that we should all pass along to those we know who are just now beginning to wonder about AGW. Many people didn’t learn much about chemistry or physics in high school, and don’t feel capable of making up their own mind on this issue because it seems so “academic” or “scientific” to them. But those same people still have common sense, and can picture themselves standing beside a giant pool of sea water, ten feet deep and 5.25 miles on each side, wondering what they could do to raise its temperature. (Somebody check my numbers, please.)
Could you supply a link to your source for the 250,000,000 tonnes per person statistic?

Invariant
October 17, 2009 9:44 am

tokyoboy (00:19:01) :
Most of the heat on the earth’s surface comes from the sun, and its intensity has been almost constant in these 100 plus years (except for a 0.1%-level fluctuation during a solar cycle).
In view of this, I now suspect, as a chemist not familiar enough with this field, that PDO, PDV, AMO etc. are caused by periodic changes of heat partitioning between the surface and underneath of the ocean, and this in turn is caused by the periodic pattern change of ocean currents (and ultimately by the periodic pattern change in the wind?).
Correct me please if such a speculation is wrong.

Sure. Even a perfectly constant (big) sun can initiate and sustain many oscillations her on (small) earth. This is for example equivalent to the reaction–diffusion systems that display a wide range of oscillatory behaviors, including the formation of traveling waves and wave-like phenomena as well as other self-organized patterns like stripes, hexagons or more intricate structure like dissipative solitons.
http://en.wikipedia.org/wiki/Reaction–diffusion_system
Possibly the nonlinear oscillations here on earth may be present on many time scales, from days, to years and centuries.

Pamela Gray
October 17, 2009 10:00 am

The following link presents information on the formation of El Nino and La Nina, including several theories regarding the cause.
http://www.crystalinks.com/elnino.html

Michael
October 17, 2009 10:01 am

“Thanks for the interesting paper … as a casual observer, it is indeed complex but it seems to reaffirm that “it is the sun stupid” and, of course, the oceans.
(May have mentioned this previously… it is my little way of feeling insignificant RE: GW.)
There are ~ 250,000,000 tonnes of ocean water for every person on earth. (The math is ~ correct.) ”
Thanks Clive,
That puts everything in perspective.

F. Ross
October 17, 2009 10:19 am

“… These results highlight the strong similarity in Pacific decadal variability on either side of the equator and suggest it may best be viewed as a reddened response to ENSO.
…”
Pardon my red face but, in the context of the paper, what does reddened mean? [Possibly warmer?]

October 17, 2009 10:28 am

PIONEERING METEOROLOGIST
Robert Fitzroy, Darwin’s captain on the Beagle, was a pioneering meteorologist.
Voyages contained detailed observations of weather conditions, on the basis of which Fitzroy was appointed to the Board of Trade in 1854 to set up “uniform meteorological observations at sea”. Royal Navy and merchant ships were asked to submit data for a general weather survey.
Fitzroy’s survey was a huge success. Initially its purpose was purely to record the weather, but he came to see that by collecting and collating data systematically over a wide area it should be possible to predict — or forecast — future weather.
http://www.timesonline.co.uk/tol/news/science/eureka/article6866634.ece
The first attempt at a general weather forecast in The Times came on July 26, 1877.
http://archive.timesonline.co.uk/tol/viewArticle.arc?articleId=ARCHIVE-The_Times-1877-07-26-10-003&pageId=ARCHIVE-The_Times-1877-07-26-10

October 17, 2009 10:44 am

What is the need of one more model if real causes are not all included, except if “conveniently adapted” to current and fleeting reality. In any moment, some unexpected (for the gamers not for true observers) and not modelled phenomena will for sure appear. This is the case of all solar models and all solar cycle forecasts based on imaginative, but not necessarily based on reality, theories.

Doug in Seattle
October 17, 2009 10:44 am

We humans have long had a rather inflated view of our importance in the grand scheme of things. The AGW movement is in my opinion just another manifestation of this phenomenon.
I suspect my views are biased from the science education I received before the advent of modern “critical thinking” in our academic system. And also perhaps from the experience I gained working in remote regions during my youth, where the scale of man is manifestly evident. My error also might have been to see computers as tools rather than instruments of revealed truth.
Perhaps I will eventually reform and adopt the “critical thinking” ways of my betters, but in the mean time I am content to be a skeptic and think my “uncritical” thoughts.

pyromancer76
October 17, 2009 11:01 am

Kate (03:25:44) :
An item appeared about this today in The Telegraph
Where Geoffrey Lean asserts that:
“Almost all climatologists expect warming to continue in the long term, but – because of natural fluctuations – they disagree about the immediate future….
You may wish to comment on that statement in the box provided on his page.
Not only comments in The Telegraph from our learned WUWT crew — but is it time for another post on the physics of CO2 that makes this long-term fright of frying fridiculous? Is there new information on the behavior of CO2 in the atmosphere that should be included?

October 17, 2009 11:17 am

reddened
I understand it to mean made more red or resulting from inflammation. I assume the usage is basically jargon for a response driven by something, or inflamed by it.
Yes?

anna v
October 17, 2009 12:03 pm

OK, here is a link for currents and tides:
http://www.aviso.oceanobs.com/en/applications/ocean/tides/tides-and-climate/index.html
“Ocean waters are stratified according to their density. The different layers mix with difficulty. However the tidal currents coming into contact with the relief of the ocean bottom (even if this is very deep) creates waves which are propagated at the interface between two layers of different densities. It is currently thought that this mechanism contributes more than half of the vertical mixing of water masses. Now this mixing is fundamental for large-scale ocean circulation (thermohaline circulation) which enables the redistribution of heat from the equator to the poles.”

Stefan
October 17, 2009 12:04 pm

gtrip (09:27:52) :
MUST READ:
http://www.quadrant.org.au/magazine/issue/2009/10/climate-modelling-nonsense

Thank you for that, it is a great piece.
As for secular humanism, it is odd to think that it would grow into a new religion, but there’s a couple more ingredients, I gather.
Postmodernism ended up combining an egalitarian cognition with a narcissistic ego. People became aware of the world, and needed that they individually be the ones who saved it. This is the source of “we’ve got to do something!” (See, we really need to, our egos depend on it.)
I’m not trying to be scathing, I feel I went through this view about 20 years ago, but passed through it because I later became exposed to other ideas.
Cognitively there are several tricks used to get round the usual practical and rational objections to such a project.
The Precautionary Principle sidesteps the scientific method of falsifiability, whilst claiming to remain scientific.
Multiculturalism is used to affirm that no one culture is better than any other, whilst kicking in the teeth Western culture of consumerism and big business, and promoting multiculturalism as the best culture.
Having said that, there are thinkers who are looking at environmental issues in a more sophisticated way, but they’re the minority for now.

anna v
October 17, 2009 12:32 pm

And another connecting the dots:
http://ocean.mit.edu/~cwunsch/papersonline/wunsch_2000_moon_climate_nature.pdf
“for such a source: winds and tides.
For over 75 years13,14 it was thought that
the tides dissipated almost entirely by friction
in the shallow seas above the continental
shelves. But Munk and I concluded3 that
about half of the power required to return
the deep waters to the surface was coming
from mixing driven primarily by dissipation
of tidal energy — principally lunar, but with
a minor solar component — in the deep
ocean (Fig. 1). Now, by fitting a dynamical
model to satellite altimetric measurements
of the tides, Egbert and Ray2 have produced
an observational estimate of 1 terawatt of
open-ocean tidal dissipation. Their numbers
are not definitive, but they are in agreement
with the energy values required by the deep
upwelling, and with the total — shallow
(about 2 terawatts) plus deep — energy
losses implied by the lunar recession.”

Steve M.
October 17, 2009 1:07 pm

Kate:

http://www.telegraph.co.uk/earth/earthcomment/geoffrey-lean/6349529/Sceptics-figures-on-global-warming-simply-dont-add-up.html
Hope that clears things up.

Nope, not really. Written by a environmentalist journalist, and just one or 2 quotes. Not heavy on the proof. GISS temperature records are poor…station siting is poor…4000 stations, mostly rural, stopped reporting in the 90’s. There wasn’t 50% coverage of the southern hemisphere until 1940. “Homogenization” of the data is questionable. Marysville station (urban setting) has no UHI adjustment in 2009, but in 1880 there is a -2c adjustment. Nice case of cool the past to make the present warmer. Satellite records are better, but essentially start at the end of a cool phase of the PDO, so I don’t think a good trend will be seen until the end of the next cool phase..in maybe 20-30 years. The only “hockey” stick type warming seen is proxy studies….see Steve McIntyre’s analysis of that. I think most skeptics will agree that since the mid 1800’s it’s gotten warmer (which of course was the end of the little ice age).

gtrip
October 17, 2009 1:54 pm

Stefan (12:04:29) :
Thank you for that, it is a great piece.
Apparently the moderator didn’t think so as my post here and on a couple of other threads have been deleted (not even “snipped”).
I thought it was an important essay in the AGW debate.

Gene Nemetz
October 17, 2009 2:01 pm

reddened
I understand it to mean made more red or resulting from inflammation. I assume the usage is basically jargon for a response driven by something, or inflamed by it.

What happens to some when you bring up Piers Corbyn.

gtrip
October 17, 2009 2:12 pm

Stefan (12:04:29) :
gtrip (09:27:52) :
MUST READ:
http://www.quadrant.org.au/magazine/issue/2009/10/climate-modelling-nonsense
Thank you for that, it is a great piece.
Apparently the moderator didn’t think so as my post here and on a couple of other threads have been deleted (not even “snipped”).
My post was even deleted from the tips and notes page.
Is Joe Romm moderating this weekend????

Gene Nemetz
October 17, 2009 5:10 pm

Clive (07:33:07) :
There are ~ 250,000,000 tonnes of ocean water for every person on earth. (The math is ~ correct.)
That would be just the surface water.

glen martin
October 17, 2009 5:34 pm

“” F. Ross (10:19:04) :
“… These results highlight the strong similarity in Pacific decadal variability on either side of the equator and suggest it may best be viewed as a reddened response to ENSO.
…”
Pardon my red face but, in the context of the paper, what does reddened mean? [Possibly warmer?] “”
I suspect it means the PDO is mainly sensitive to the longer term variations in the ENSO (year to year instead of month to month)
The term may originate from the fact that red light has a longer wavelength than blue light.

F. Ross
October 17, 2009 5:55 pm

glen martin (17:34:44) :
Thanks. Sounds plausible.

Ninderthana
October 17, 2009 6:13 pm

I hate to put a spanner in the works but simple logic tells you that this paper and the model it is based upon is a load of heiffer dust.
Please read my arguements at:
http://astroclimateconnection.blogspot.com/2009/10/which-came-first-chicken-or-egg.html

Clive
October 17, 2009 7:05 pm

Cap’n Rusty and Michael…
Mods: This is a bit OT. Bear with me.
I was slightly off…
To be safe, use 200,000,000 cubic meters per person. With such huge numbers being off a wee bit is not critical. It is the concept (of BIG) one is trying to convey.
I did all of calculations again with some references. If you want a copy you can send an email to: clives at shaw dot ca
Here is the conclusion: For the purpose trying to form a mental image of this amount of water, it is suitable to say “there are about 200,000,000 cubic meters of sea water per person on earth.”
That is equivalent to a lake that measures 10 meters deep by 4,000 meters (4 km) by 5,000 meters (5km) PER PERSON.
A “lake” for a family of five therefore has about 1 billion cubic meters of seawater. This a body of water that is 10 meters deep by 10,000 meters (10 km) by 10,000 meters (10 km).

It is a lot of water. I feel insignificant when I try think how I might possibly have an affect on it. Maybe this line of thinking is silly, but it works for me. ☺
Clive

Clive
October 17, 2009 8:01 pm

Gene… “That would be just the surface water.”
No, that is tonnage based on cubic meters. They are close to the same.
Has nothing to do with “surface.”
I initially uses tonnes. It is probably more sound to use cubic meters.
The figure was recalculated and is closer to 200,000,000 cubic meters. (And slightly more tonnes because sea water weights about 1.03 t/m3.)
Cheers!
Clive

Ninderthana
October 17, 2009 10:06 pm

Anna V.
For starters try:
Keeling and Whorf (1997) Proc. Natl. Acad. Sci., 94, pp. 8321 – 8328
“Possible Forcing of Global Temperature by the oceanic Tides”.
Keeling and Whorf (2000) PNAS, Vol 97., No. 8., pp. 3814 – 3819
“The 1800 year tidal cycle: A Possible Cause of Rapid Climate Change”.
Munk and Wunsch (1998) Deep Sea research Part 1, 44, pp. 1977 – 2010
“Abysmal Recipes II: Energetic of Tidal and Wind Mixing”
Egbert and Ray (2000) Nature, June 15th, Vol. 405, p. 775
“Significant Dissipation of Tidal Energy in the Deep Ocean Inferred from Satellite Altimeter Data”.
I apoligies if you have already heard of these references.
I am about to submit a paper for publication that shows that, between 1800 and 2002, the strongest extreme proxigean spring tides (EPST) that are nearest perihelion are preferrentially found in the starting years (or one year prior to the starting years) of El Nino events. Similarly, the weakest EPST that are near aphelion avoid the years leading up to El Nino events.

anna v
October 17, 2009 11:44 pm

Ninderthana (22:06:24) :
thanks.
One more case of “the science is not settled”, imo.

Paul Vaughan
October 18, 2009 12:16 am

Re: Ninderthana (18:13:35)
Thanks for the notes you left April 29, 2009:
“Misunderstandings about the Pacific Decadal Oscillation”
http://wattsupwiththat.com/2009/04/28/misunderstandings-about-the-pacific-decadal-oscillation/
[Ninderthana (05:52:17)]

Paul Vaughan
October 18, 2009 12:33 am

anna v,
Links for some of the papers listed by Ninderthana:
Keeling, C.D.; & Whorf, T.P. (1997). Possible forcing of global temperature by the oceanic tides. Proceedings of the National Academy of Sciences of the USA 94(16), 8321-8328.
html:
http://www.pnas.org/content/94/16/8321.full
pdf:
http://www.pnas.org/content/94/16/8321.full.pdf
Keeling, C.D.; & Whorf, T.P. (2000). The 1800-year oceanic tidal cycle: A possible cause of rapid climate change. Proceedings of the National Academy of Sciences of the USA 97(8), 3814-3819.
html:
http://www.pnas.org/content/97/8/3814.long
pdf:
http://www.pnas.org/content/97/8/3814.full.pdf
Beyond this:
I recommend looking into the works of Yu.V. Barkin.

Mike
October 18, 2009 5:50 am

Several people have suggested above that “natural variation in the short term isunpredictable but the long term can be predicted”.
This really shows the limited knowledge of noise in natural systems of the writers. What they seem to be referring to is the properties of so called “normal”, “guassian” or “white noise”, which has equal power in equal frequency windows. This does have the property that long term noise is much smaller than short term noise and simple smoothing quickly reduces the noise.
However, there are plenty of systems where the noise level varies with frequency and 1/f noise aka (pink – i.e. reddy, low noise white) is quite typical of many natural systems. Such noise does not show the “it will all smooth out if we average enough points” of the naive commentators here. In contrast, because low noise predominates, averaging out can lead to INCREASING the amount of noise present. Or to put that in concrete terms, the natural noise of global temperature may well have noise components in the decadal, century and millennia time periods that are much larger than short term year-to-year variation.
For a totally impartial prediciton of global temperature see this graph:-
http://www.tursiops.cc/fm/pink.gif
from site: http://www.tursiops.cc/fm/

Ninderthana
October 18, 2009 7:25 am

Mike,
Your arguments may have some meaning in a climate system whose variability is exclusively driven by internal fluctuations. However, it you are dealing with climate system that is being driven by an outside forcing agent
like the Moon (such as the PDO and ENSO) then you have a different kettle of fish.
I will soon be publishing evidence that shows that the onset of El Nino-ENSO events are synchronized with the onset of the strongest extreme proxigean spring tides (EPST). Not only that, I will be showing that the pumping frequencies of the EPST closely match those observed in the ENSO indices between 1950 and the present. They also naturally produce the observed 20 year and 65-70 year peridicities in the PDO as well.
Unfortunately, you are going to have to wait till I can get this work through peer-review before you can see the actual evidence.

Paul Vaughan
October 18, 2009 4:20 pm

Re: Ninderthana (07:25:07)
Have you ruled out the possibility of 2 (or more) varieties of El Ninos?
There are time-intervals for which there is rigid phase-concordance between contrasts of annual & interannual geomagnetic aa index and SOI (& for other climate indices as well).
Furthermore, wavelet-crosses of solar variables & terrestrial polar motion show patterns that match the time-integrated PDO. There appears to be a possible relationship with the period of ENSO; one of the patterns I’ve found is anything-but random (but I’ve not yet finished the analysis…)

Paul Vaughan
October 18, 2009 5:08 pm

Remember the phase-reversals in relationships between SST & solar cycles (that many have tried to sweep under the rug)?
Reminder – Figures 7 & 8:
Abarca del Rio, R.; Gambis, D.; Salstein, D.; Nelson, P.; & Dai, A. (2003). Solar activity and earth rotation variability. Journal of Geodynamics 36, 423-443.
http://www.cgd.ucar.edu/cas/adai/papers/Abarca_delRio_etal_JGeodyn03.pdf
Compare with:
http://www.sfu.ca/~plv/SSBx_LR.(67mo)_11.1a.png
http://www.sfu.ca/~plv/SSBy_LR.(67mo)_11.1a.png
http://www.sfu.ca/~plv/SSBz_LR.(67mo)_11.1a.png
Also: Compare with the JS-timescale (19.86a) pattern here …
http://www.sfu.ca/~plv/RegimeChangePoints.PNG
…and with …
http://www.sfu.ca/~plv/r_r.._12.8a.png

Paul Vaughan
October 18, 2009 9:18 pm

For reference:
ENSO Period (in years):
1) http://www.sfu.ca/~plv/PeriodAusSOI_MorletPi.PNG
using http://www.sfu.ca/~plv/WaveletMorletPi.PNG
2) http://www.sfu.ca/~plv/PeriodAusSOI_MxSh.PNG
using http://www.sfu.ca/~plv/WaveletComplexMexicanHat.PNG
Note: Power is time-normalized.
Compare change-points from the above with those here:
http://www.sfu.ca/~plv/Pr.-LR.(67mo)11.1a.png
This shows the phase-difference between terrestrial polar motion and the solar cycle at the (average) timescale of the solar cycle.
Supplementary:
Phase-contrast of solar cycle & stationary 11.1a wave:
http://www.sfu.ca/~plv/Stn11.1a_vs_LR.(67mo).png

October 22, 2009 10:17 am

Like it or not, the differences in culture are obvious and absolute. ,