This paper is to be published on-line on Friday in Physics Letters A Dr. Douglas graciously sent me an advance copy, of which I’m printing some excerpts. Douglas and Knox show some correlations between Top-of-atmosphere radiation imbalance and the Pacific Decadal Oscillation (PDO). The authors credit Dr. Roger Pielke Sr. with reviving interest on the subject due to his discussions on using ocean heat content as a metric for climate change.
Abstract
Ocean heat content and Earth’s radiation imbalance
D.H. Douglass and R, S, Knox
Dept. of Physics and Astronomy, University of Rochester, PO Box 270171, Rochester, NY 14627-0171, USA
Earth’s radiation imbalance is determined from ocean heat content data and compared with results of direct measurements. Distinct time intervals of alternating positive and negative values are found: 1960–mid-1970s (−0.15), mid-1970s–2000 (+0.15), 2001–present (−0.2 W/m2), and are consistent with prior reports. These climate shifts limit climate predictability.
Introduction:
A strong connection between Earth’s radiative imbalance and the heat content of the oceans has been known for some time (see, e.g., Peixoto and Oort [1]). The heat content has played an important role in recent discussions of climate change, and Pielke [2] has revived interest in its relationship with radiation. Many previous papers have emphasized the importance of heat content of the ocean, particularly the upper ocean, as a diagnostic for changes in the climate system [3–7]. In this work we analyze recent heat content data sets, compare them with corresponding data on radiative imbalance, and point out certain irregularities that can be associated with climate shifts. In Section 2 the conservation of energy is applied to the climate system and the approximations involved in making the radiationheat content connection are discussed. In Section 3 data sources are enumerated. Section 4 gives the radiation imbalance for the Earth’s climate system. In Section 5, climate shifts, radiative imbalances and other climate parameters are discussed. A summary is in Section 6.
Discussion:
…
What is the cause of these climate shifts? We suggest that the low frequency component of the Pacific Decade Oscillation (PDO) may be involved. The PDO index changes from positive to negative near 1960; it remains negative until the mid-1970s where it
becomes positive; then it becomes negative again at about 2000. This mimics the FTOA data. The PDO index is one of the inputs in the synchronization analysis of Swanson and Tsonis [43]. One would like to be able to predict future climate. Such predictions are based upon the present initial conditions and some expectation that changes in the climate state are continuous. However, if there are abrupt changes such as reported by Swanson and Tsonis then this is not possible. These abrupt changes presumably
occur because the existing state is no longer stable and there is a transition to a new stable state.
Summary:
We determine Earth’s radiation imbalance by analyzing three recent independent observational ocean heat content determinations for the period 1950 to 2008 and compare the results with direct measurements by satellites. A large annual term is found in both the implied radiation imbalance and the direct measurements. Its magnitude and phase confirm earlier observations that delivery of the energy to the ocean is rapid, thus eliminating the possibility of long time constants associated with the bulk of the heat transferred. Longer-term averages of the observed imbalance are not only many-fold smaller than theoretically derived values, but also oscillate in sign. These facts are not found among the theoretical
predictions.
Three distinct time intervals of alternating positive and negative imbalance are found: 1960 to the mid 1970s, the mid 1970s to
2000 and 2001 to present. The respective mean values of radiation imbalance are −0.15, +0.15, and −0.2 to −0.3. These observations are consistent with the occurrence of climate shifts at 1960, the mid-1970s, and early 2001 identified by Swanson and Tsonis. Knowledge of the complex atmospheric-ocean physical processes is not involved or required in making these findings. Global surface temperatures as a function of time are also not required to be known.
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I think a lot of the resistance to the idea of the oceans storing heat on a long term basis, is because of the AGW idea of ‘heat in the pipeline’ from the greenhouse effect.
The air doesn’t heat the oceans, it’s the other way round, so we can forget that daft notion. However the heat in the pipeline is real enough. It is solar derived heat, and we should be grateful for it, because if the sun goes into a funk like it did at the start of the 1800’s, we’ll be glad that it previously charged the ‘oceanic capacitor’ with a run of high solar cycles.
Kevin Kilty (05:20:53) :
A somewhat pedantic point of physicists is that one refers to heat as energy during transfer only.
Although you find this pedantic, I beleive that we all communicate better when terms are well defined and used in an accurate manner. “Heat” and “energy” are well defined, but the misuse of the term “heat” when “energy” is meant is rampant. See the phrase “ocean heat content”.
Mike McMillan (06:32:40) :
I’ve seen little discussion or estimates of the amount of energy that gets converted into work (the Physics 101 definition), rather than just being input and then exhausted from the earth climate system.
This may not be the secret hidden heat sink that some modelers seek, but it’s surely a part of it, and can’t continue to be ignored.
The bottom line is that heat in = heat out, more or less.
What the internal elements of the system get up to in between is a fascinating study, but doesn’t affect the overall equation governed by the laws of thermodynamics in the (very) long term.
However, you are right to point it up, because a failure to appreciate the variety of ways in which the biosphere, oceans and atmosphere and the Earth itself shift heat around, hiding it from the surface temperature record, is in large measure responsible for the misconceptions of oversimplyfudging climatologists and physicists alike.
par5 (02:00:48)
“Glad to see someone correctly call it a radiation ‘imbalance’. Leif also has a point about heat storage- there is no heat in the oceans that rise to the surface. Heat accumulates at the surface, then diffuses. The wind draws some of this away. The sun is not powerful enough to warm oceans, just the surface.”
The oceans surface waters (~ 100 m) are directly warmed by solar radiation.
By their very nature radiative waming and cooling processes are very rapid when you are talking about multi-year time scales.
Despite the hourly, daily and annual changes in radiative losses and gains
to the (tropical) oceans heat content, you can still talk about a long term average heat content. It is the varaition of this long-term average heat content of the upper surfaces of the (tropical) oceans that is in question.
One factor none of you are seeming to consider is the up welling deep cool ocean water. It is well know that up welling of this cool water has an significant impact up long-term ocean temperatures, independent of the
instantaneous radiative heat balance.
Long-term changes in the up welling of cool deep ocean water (aka the PDO) goven the level of long-term radiative losses from the ocean surface and indirectly the long-term changes in the OLR.
The significant role of the PDO argued for by this paper is significant in relation to the role of the Sun. This is because evidence is accumulating that the Lunar Nodal Cycle is one of the key drivers of the PDO.
During late April/early May this year there was a good paper, a fascinating and informative discussion and many relevant, authoritative links about the PDO on WUWT here: http://wattsupwiththat.com/2009/04/28/misunderstandings-about-the-pacific-decadal-oscillation (aka http://tinyurl.com/mt5vwu ).
It seems that it is well established that the PDO is now in its negative phase and that this means a colder climate for North America.
In a paper published in March this year, Dr. Ichiro Yasuda, Professor, Ocean Research Institute, The University of Tokyo, showed that the Luna Nodal Cycle is a key driver of the PDO.
The citation is: Yasuda, I. (2009), ‘The 18.6-year period moon-tidal cycle in Pacific Decadal Oscillation reconstructed from tree-rings in western North America’, Geophysical Research. Letters, 36, L05605, doi:10.1029/2008GL036880.
Here is the Abstract:
“Time-series of Pacific Decadal Oscillation (PDO) reconstructed from tree-rings in Western North America is found to have a statistically significant periodicity of 18.6- year period lunar nodal tidal cycle; negative (positive) PDO tends to occur in the period of strong (weak) diurnal tide. In the 3rd and 5th (10th, 11th and 13rd) year after the maximum diurnal tide, mean-PDO takes significant negative (positive) value, suggesting that the Aleutian Low is weak (strong), western-central North Pacific in 30–50N is warm (cool) and equator-eastern rim of the Pacific is cool (warm). This contributes to climate predictability with a time-table from the astronomical tidal cycle.”
The last LNC maximum happened on September 16, 2006. According to Prof Yasuda’s finding, the PDO should now be taking a significant negative value, as is being found. The climate consequences are therefore as expected.
There is substantial evidence that the LNC is a significant contributor to our planet’s climate dynamics. I include a carefully written and illustrated explanation of the LNC and review a lot of the published literature about its contribution to climate dynamics in my paper “The Sun’s role in regulating the Earth’s climate dynamics” published in the Journal of Energy and Environment Vol 20 No 1 2009. A copy of my paper and the new GRL one by Prof Yasuda is in the files section of the site.
Amongst other things I wrote:
“The ocean currents generated by the northward movement of the tidal bulge, in conjunction with the rotation of the Earth through the bulges in the normal manner creating our experience of the tides, brings warmish equatorial water to the Arctic accelerating the warming that had being going on there because of other forms of solar activity as discussed below.
The LNC has maximum effect at higher latitudes, resulting in higher sea levels at these latitudes. It creates tidal currents resulting in diapycnal mixing, bringing the warmer equatorial waters into the Arctic. The LNC is therefore a major determinant of Arctic climate dynamics, influencing long term fluctuations in Arctic ice. As a result, it is a key driver of European climate.”
The LNC is but one of the many ways in which the Sun most likely regulates our climate. The Sun’s role in speeding up or slowing down the Earth’s rotation is another as there is a rather well established relationship between decadal variations in rotation and climate. (Briefly, a decadal rotation decrease (increase) results in planetary cooling (warming)) with a lag of about 6 years. 6 years ago rotation was slowing down.
It is to be noted that it is most likely that the Sun’s impact on our climate dynamics is greatest because of the interaction between the several solar variables than because of any one of those variables on their own.
There is also a very good paper accompanied by useful discussion and web links about the LNC on WUWT here:
http://wattsupwiththat.com/2009/05/23/evidence-of-a-lunisolar-influence-on-decadal-and-bidecadal-oscillations-in-globally-averaged-temperature-trends/#more-7965
(aka http://tinyurl.com/mrjq9e )
Lief:
A large annual term is found in both the implied radiation imbalance and the direct measurements. Its magnitude and phase confirm earlier observations that delivery of the energy to the ocean is rapid, thus eliminating the possibility of long time constants associated with the bulk of the heat transferred.
If so, debunks the idea [kicked around many times on this blog] of the oceans storing the heat of past high solar cycles to release it when cycles are low.
I dunno Lief … the paragraph says “to the oceans” .. not “from” the oceans. I’m not up on it, but maybe you could shed some light on it .. .the rate of heat transfer mechanisms … energy in as light [transformed into heat] vs energy out as heat by convection, conduction and evaporation.
If the ocean is incapable of storing heat, then there can be no long-term temperature gradients.
So, if you take the oceans out of the equations for changes in climate, then you turn around and take the sun out totally, a paradox is created.
Before man burned fossil fuels, there was no climate change.
The clergy saying prayers in front of advancing glaciers in the Little Ice Age and the ancient man they found frozen in the Alps are fakes.
Wolly Mammoths are elaborate hoaxes.
The Vikings in Greenland and Newfoundland didn’t perish from crop failures due to lack of growing season, they drank too much beer and passed out in snow and died of hypothermia.
All the glaciers we have were there since the beginning of time, and once they melt, they cannot reform.
Climate change is impossible.
There can be only climate variation in a finite range.
The Earth is restored to it’s pre-scientific flatness.
We have new green jobs for lots of people:
Stone cutters for temples and statues of idols.
How could there be a positive feedback from c02? It takes a lot of energy to heat oceans, which have a higher heat capacity that air. In other words, the energy required to heat the oceans by 1C is far greater than the energy required to heat the troposhere by 1C. Longwave radiation doesn’t penetrate the oceans.
“Bob Tisdale (04:19:09) :
Stephen Wilde: You wrote, “The solar input varies over century timescales, the rate of energy release from ocean to air varies over multidecadal timescales with the PDO as the largest component.”
Two things: On whose TSI data are you basing the assumption that “solar input varies over century timescales?” Are you still using Lean at al?”
I have noted the revised TSI data from Leif amongst others. Although the range of variation is much reduced the general pattern of rising and falling over the centuries remains. In any event I see TSI as only a proxy for solar input to the Earth’s system and not necessarily definitive
“Second, the PDO does not reflect SST or OHC. It reflects the PATTERN of SST anomalies for only the North Pacific, north of 20N. It’s ENSO that discharges and recharges OHC, not the PDO”
I have previously accepted that PDO is just a statistical artifact arising from ENSO events but have also noted a real phenomenon behind it. Since that real phenomenon is not adequately described by the term PDO I have suggested the term ‘Wildean Ocean Cycles’ Thank you for the opportunity to put that forward again.
Anyway it is the net behaviour of all the oceans combined together with variations in solar activity that discharges and recharges OHC not just ENSO.
Leif Svalgaard (23:27:06) :
“A large annual term is found in both the implied radiation imbalance and the direct measurements. Its magnitude and phase confirm earlier observations that delivery of the energy to the ocean is rapid, thus eliminating the possibility of long time constants associated with the bulk of the heat transferred.”
If so, debunks the idea [kicked around many times on this blog] of the oceans storing the heat of past high solar cycles to release it when cycles are low.
So what’s the connection to PDO? It seems to me that they are implying both a “large annual term” as well as some kind of longer term process. Now that longer term process may have nothing to do with oceans “storing the heat of past high solar cycles to release it when cycles are low.” But I don’t think the “large annual term” is the whole story here.
In my continuing explorations into the mysteries of the global temperature time series, I’ve recently determined that it can be decomposed into two components, one having a high Hurst exponent (long time persistence), and the other having a low Hurst exponent (anti-persistence, or mean reversion). The latter property fits with the notion of a “large annual term” because it shows the climate system rapidly responding to inputs (shocks) by quickly moving back toward a mean. The former — a component with a high Hurst exponent — is characteristic of cycles on decadal and multidecadal time frames, like (but not necessarily the same) as the PDO.
So I do not necessarily see an inconsistency between “a large annual” term along with a longer, low frequency, process at work. Now whether that longer process is the ocean releasing heat stored from higher solar cycles, I haven’t a clue. In fact, I’d think rather not, at least in the sense I’m thinking here of longer term “cycles,” since storing up heat from high solar cycles, only to release it during low solar cycles, would lead to a non-cycle (stasis) in the long term “second order” process.
But don’t worry, Leif. While I may not buy into the “storing up heat from high solar cylces, only to rlease it during low solar cycles” argument (yet? — my mind is never closed to new data), I can still see the sun at work in the global temperature time series (in the component with the high Hurst exponent mentioned above). 🙂
FAO uses LOD (Length of the day) to succesfully predict sea temperatures in order to forecast fish catches:
http://books.google.com.pe/books?id=q3mGCiLjkBIC&pg=PP6&lpg=PP6&dq=fao+fish+catches+lod&source=bl&ots=eeMbbzxmCt&sig=LOTxBsFpDgQRKtMq5ROMiwEbFS0&hl=es&ei=XtSCSuWFBNWLtgeLnK3WCg&sa=X&oi=book_result&ct=result&resnum=4#v=onepage&q=fao%20fish%20catches%20lod&f=false
Leif – Tallbloke asked you something on an earlier thread that, as a non-scientist, I would be interested in your answer. I direct the question to you as you obviously spend a good portion of your time pondering such questions. It went like this …
oops – didn’t close the blockquote properly – tallbloke only responsible for the first paragraph
cal (01:31:27) :
Leif Svalgaard (23:27:06) :
A large annual term is found in both the implied radiation imbalance and the direct measurements. Its magnitude and phase confirm earlier observations that delivery of the energy to the ocean is rapid, thus eliminating the possibility of long time constants associated with the bulk of the heat transferred.
If so, debunks the idea [kicked around many times on this blog] of the oceans storing the heat of past high solar cycles to release it when cycles are low.
As I posted previously, there is chart in the Climate4you website that shows the correlation between long wave radiation at the equator and temperature. This clearly shows that, in general, the temperature and radiation are anticorrelated. This supports your comment that the temperature is caused by the radiative imbalance rather than heat being stored in the sea during previous warming periods and then released. The only exception is the 1998 el nino and the months immediately before and after. During this period the radiation and temperature were correlated indicating that in this exceptional situation stored energy was released.
I see a chart at this URL,
http://www.climate4you.com/GlobalTemperatures.htm#Outgoing long wave radiation above Equator
But rather than anticorrelation, I see a phase lag of about one year in the presense of longer period variation. The air temperature peaks, and this is followed about a year later by a peak in the LW radiation. Note that the graphs do not actually cover the same portion of the globe, a lot of the western Pacific is excluded from the LW data. At any rate, phase is notoriously difficult to unwind in time series and so determining the phase relationship as a function of period is not yet clear to me, but a cursory look seems the relationship is the reverse of what you claim.
Please look at this curve, a forecast to 2099, and see where we are at now:
http://www.giurfa.com/fao_temps.jpg
The virus “GWCC-1998” (global warming/climate change) has suddenly attacked one of WUWT most serious blogger:
I have just [in another thread] been lectured that the oceans contains no heat, as heat cannot be stored, so what is this whole paper about?
I am sure it was a joke.
Re: solar and barycenter. A faster oscillating event has a pretty good chance of occurring simultaneously with a slower oscillating event and yet have no connection whatsoever between the two. Mechanism people. Mechanism.
Re this thread: Very satisfying. Very satisfying indeed.
coaldust (06:54:45) :
Kevin Kilty (05:20:53) :
A somewhat pedantic point of physicists is that one refers to heat as energy during transfer only.
Although you find this pedantic, I beleive that we all communicate better when terms are well defined and used in an accurate manner. “Heat” and “energy” are well defined, but the misuse of the term “heat” when “energy” is meant is rampant. See the phrase “ocean heat content”.
I agree with coaldust. This AGWers are trying to change even the meaning of the physical concepts. The thing is quite clear, although many are trying of confusing it:
Heat is a process quantity.
Internal energy is a state function.
Systems cannot store process quantities and no system can have a “content” of a process quantity.
You can store energy into a system like internal energy.
People saying “Heat content in the oceans” are misusing the real physical concept of heat. The correct form is “Total of energy stored in oceans”, or simply “Content of internal energy in oceans”.
The abstract ends with: “These climate shifts limit climate predictability.
Not necessarily. First of all, while Douglass and Knox position their paper in terms of Swanson and Tsonis, who treat climate shifts are part of a reorganization of a chaotically dynamic system, that is not the same thing as saying that the climate shifts are unpredictable. However, I think the jury is still out on the mechanism proposed by Swanson and Tsonis to explain climate shifts. Since these are all efforts to explain long lived, low frequency processes like the PDO, I’m not sure that any mechanism can be demonstrated completely with reference only to data from the instrumental period. After all, what looks like a sharp structural break in the PDO may simply be the transition point in cycle that lasts 50 to 60 years, a cycle that may have other, shorter term cycles imposed on top of it, and on top of all that maybe an essentially random or mean reverting variation on a short term (monthly to annual) basis. With cycles of this duration, I think the jury stays out until we have a mechanism that also explains the evidence for the PDO in the proxy data record.
In any case, Swanson and Tsonsis don’t seem to agree on what their research means:
http://climateresearchnews.com/2009/07/natural-climate-shifts-swanson-v-tsonis/
“But don’t worry, Leif. While I may not buy into the “storing up heat from high solar cylces, only to rlease it during low solar cycles” argument (yet? — my mind is never closed to new data), I can still see the sun at work in the global temperature time series (in the component with the high Hurst exponent mentioned above)”
Basil,
Think “storing up cold” instead of “storing up heat.” The cold gets stored in deep ocean reservoirs during Grand Minima by cold salty water released during the freezing process. Then it mixes with the warm surface water more quickly at first, then more slowly as the cold reservoirs are depleted. This results in a long term warming trend which will continue until the next Grand Minimum.
“Just togive some relative sense of scale, the Three gorges dam is around 30 cubic km once filled. The thermal expansion of the oceans is around 5400 cubic km and that’s just 1993-2003.”
That’s interesting tallbloke but hardly relative to all the land sequestration of water involved. If you have the scientific evidence to show new dam construction is minor when measuring sea level variations then perhaps you should publish a rebuttal to the paper I cited which was peer reviewed and in a reputable journal. As far as the sea level rise as attributed by the IPCC I don’t see anything about deforestation. I don’t see anything about ground water use. Perhaps this is because they are too small to matter, or perhaps this is because they are too difficult to measure. I would lean towards too difficult to measure. I also see nothing about Earth expansion. Can you point out what expansion rate they use?
I understand there are problems with direct temperature measurements. That doesn’t mean that we should have to accept a different flawed method. Telling me to go prove it is a weak response and shows you have no real answers to my points. It is enough that I have pointed out several significant factors that are being ignored.
rbateman (07:31:52) :
We have new green jobs for lots of people: Stone cutters for temples and statues of idols.
Things are worst than previously thought.
As I have just written in another post:
But this issue of climate change and/or global warming has become a real psychic pandemia. It should be analyzed and treated as a health problem and as such, to seek to stop its propagation. If you do not do something in this respect you will suffer the consequences of it. This is a serious matter for you. We know this as foreing bloggers at WUWT and expectators of this peculiar madness.
Don’t you think so?
steve (06:17:22) :
Good points about the issues with sea level rise. Warmists cite sea level rise as absolute and unqualified proof that the seas are gaining heat. They seem to allow for no other physical causes for apparent sea level rise than thermal expansion.
Is it true that oceanic bottomwaters were as warm as 15°C during the end of the Cretaceous?
Errata: where written “expectators” read spectators. Thanks.