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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In the context of ocean heat content and the radiation balance, it may be worth pointing out that outgoing longwave radiation from the surface climbed by 4W/m^2 from around the turn of the millenium, and has stayed at that elevated value since.
This matches the 4/m^2 my calculations on the solar/cloud forcing on the ocean from 1993-2003 quite well in terms of magnitude. It looks like the oceans went into heat release mode after the solar cycle 23 peak in ~2002. This led to some el nino’s and then falls in OHC and then SST from 2005.
I speculate that the normal decadal fluctuation rate of OLR has stayed high for longer than usual because of the non-appearance of solar cycle 24 in any active sense. It will be interesting to see the rate at which the curve decays, and whether this seems to be proportional to the drop in average SST’s which started in 2005.
That should tell us something about the extent to which the oceans store energy, and the mode in which it releases it again.
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 the oceans, just the surface. I dive in open water, so this is my observation.”
This may be apropos of nothing but this comment and the topic in general reminded me of a story one of my college math professors told. The class was differential equations and we were discussing heat transfer. He took a break from the hardcore math for a moment to tell an anecdote about some research he had been involved with to measure the amount of heat that was coming out of the core of the earth. Seems they couldn’t simply put a thermometer in the dirt at the surface of the earth because it would be subject to influences from the sun. The yearly heat pulses traveled slowly through the earth and were measurable as basically sinusoidal signals every few feet. So they needed some place that was not influenced by the sun. The place they chose was the bottom of Lake Superior because it is so deep (1000 ft in some places) that the sun never reaches the bottom. However, they still needed to subtract out the temperature of the water in order to accurately isolate the heat coming from the earth. So they put thermometers on the bottom that measured the water temp. What they found was that the temperature was nearly constant at 40F (or something really cold like that) for nearly all year until about December. Then all of the sudden the temperature spiked up (though, I can’t remember how big the spike was in degrees, so “spike” is a relative term). It turns out it took it that long for the heat from the summer to make its way down to the bottom. (Note: this was 25 years ago so I may not be remembering everything correctly and I might be leaving out some context — but that is the gist of it as I remember it).
So, for whatever it’s worth (and maybe it’s not much) this anecdote suggests to me that maybe heat does not all dissipate from the surface. I know next to nothing about fluid dynamics, but I would guess that in a huge roiling cauldron like the oceans or the Great Lakes you might see some complicated and unexpected phenomenon happening.
Stephen Wilde (07:35:38) :
Bob Tisdale (04:19:09) :
—————————-
Bob,
What do I have to say to get you to acknowledge that the PDO is more than just an artifact of ENSO?
Stephen is on to something here. Climate cycles are not just driven by oceans. More heat gets moved around the earth by atmospheric circulation than by ocean circulation, and faster, too. So when things disturb, or change, long term patterns of atmospheric circulation, we get climate change.
Don’t put all your climate eggs in the ENSO basket, please. 🙂
Basil
Stephen Wilde: You wrote, “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.”
Show me with data and graphs, please. I’m a visual person.
And as noted above. Pavlakis et al (2008)…
http://www.atmos-chem-phys-discuss.net/8/6697/2008/acpd-8-6697-2008-print.pdf
…illustrated that downwelling shortwave radiation (and for the tropical Pacific it’s “the component of the net heat into the ocean with the largest magnitude”) increases over the Pacific Warm Pool, and the increase in DSR is significant, 25 watts/sq meter during the 1997/98 El Nino.
http://i41.tinypic.com/2435kbb.jpg
*********
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 the oceans, just the surface. I dive in open water, so this is my observation.
********
There seems to be a lot of confusion concerning heat. All solids, liquids and gasses contain heat. If one could cool a substance to absolute zero, it would contain no thermodynamical heat. But due to the fact that elements and molecules have a quantum ground state, the element or molecule can be cooled only to that small but positive temperature and therefore contains heat. So, one could say that heat is “stored” or contained by all substances. I believe what is implied when one says heat is stored in the ocean is that a body of water warmer than the surrounding oceans, warmed by the
Sun for example, submerges, circulates in the ocean for some period of time, then reemerges as a body of water warmer than the surrounding water. Of course, it could reemerge in a body of water warmer than it and would then have a cooling effect at that location.
Nogw (07:46:41) :
FAO uses LOD (Length of the day) to succesfully predict sea temperatures in order to forecast fish catches
No, they do not. Because LOD is not forecast. What they noted was that there is a 55-60 year cycle in the catches and also in LOD. Good catch depends on temperature, moment of inertia of oceans and atmosphere depends on temperature, and LOD therefore also.
I’ve once read that it can take hundreds of years for ocean water to travel through an entire cycle (e.g. flow from tropics to arctic waters, cool down, sink, travel towards tropics, warm up, surface, etc.). So is it such a weird thought that some years, the sinking water is slightly warmer, and thus, many years later, the surfacing water will be slightly warmer as a result? Or has this been discussed before? (in that case, please reference).
Kevin Kilty: You wrote, “And, if Bob Tisdale, were on this post he’d undoubtedly bring up ENSO, in which storage and release takes place over many years, and the storage and release are not symmetric.”
I’ve commented a few times on this thread about ENSO.
An El Nino in a one year period can release enough heat from the tropical Pacific to cause a significant upward step change in mid-to-high latitude TLT anomalies of the Northern Hemiphere.
http://i42.tinypic.com/e9b04g.jpg
El Nino and La Nina events also dictate year-to-year variations in tropical TLT anomalies. Heat is released into the atmosphere during El Ninos and absorbed from the atmosphere during the La Ninas. Discharge/recharge.
http://i43.tinypic.com/2isid84.jpg
Those graphs are from this link:
http://bobtisdale.blogspot.com/2009/06/rss-msu-tlt-time-latitude-plots.html
I’m always happy when I read that somebody has actually measured something. It is a lot more satisfying than reading that somebody’s computer successfully ran through some program code without crashing.
But; if that something that somebody “measured” happens to be some global phenomenon; such as heat content of the oceans (all of them); well alarm bells go off.
Dipping a thermometer in San Francisco Bay just off the St Francis Yacht Club Headquarters; is not a sufficient measurement of the ocean’ s heat content.
Measuring the ocean’s heat content is even more troublesome than measurting the earth’s mean surface temperature, because that heat content problem is a three dimensional problem, whereas surface temperature is only two dimensions.
So forgive me if I am less than enthusiastic about somebody’s claim to have measured the earth’s oceanic heat content; even once, let alone multiple times to show how it may have changed.
Andybody who wants to measure the oceanic heat content of the earth is advised to buy a book on the theory of sampled data systems, and read it.
George; we are not impressed.
Come on you guys,what is preventing the ocean waters from completely freezing up?
coaldust (06:54:45) :
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 take your point well that we all need to be precise, but sometimes being terribly precise is also being pedantic. Heat is energy, and I guess I’d need an example of where the finer points of how much energy the heat implies has caused a problem on this thread. My point to Leif was that someone could claim that the ocean contained no heat if it occurred at such a low temperature that the heat could be put to no use (i.e. had no availability as engineers would say). I would assume that someone who says “ocean heat content”, means the useful energy in the ocean, that is the mass of the ocean times a specific heat times some temperature difference, but to state things like this all the time would make me a pedant.
Leif, thanks for the context, I’ll go have a read of it.
George E. Smith (09:38:43) :
This is what profiling and objective mapping are for. And yes, it is a difficult problem.
Some of the people working on this have read those books. Others are actively developing the theory. Why would you expect differently?
The Sun can directly warm a body of water to teh depthe that sunlight is completely abosrbed, below whic it is dark and the oceans then only heat by conduction and convection and mixing.
As long as the data used in HADCRUT are not freely available -see Climateaudit for this- and that HADCRUT results therefore cannot be independently replicated, any model, any research trying to fit anything – for or against- into the published HADCRUT curve is in my opinion at great risk of instant oblivion the moment HADCRUT is replicated.
Yet in so many discussions, what’s missing is how any solar or other influence is “translated” into meteorological data that in turn will become, over time, climate. The fixation on the one parameter -Hadcrut temperature- is blinding and misleading. In particular, the general atmospheric circulation is the key to understanding how those effects are playing. That is why it is unbelievable that Marcel Leroux’s work is so neglected. In fact, his reconstruction -I do not say model- of the general circulation, based on observed facts, satellite imagery and meteorological realities initially during extensive studies of weather and climate of tropical Africa, later extended to the entire globe is the missing link between the numerical models validation. Specifically the 1970s climatic shift is well documented in his work.
Between models’ run and the multiple possible answers they give (summarized as GI=GO) i.e. subjective, tweaking of parameters in order to fit the expected result, hardly an independent proof of anything, and theories such as Svenmark’s or observations from solar scientists and geophysicists researches, the only verification will come from observed meteorological data and their evolution in time. That is where Leroux’s work is invaluable as it constraints both models and the research for the cause of variations.
The second English edition of Leroux “dynamic analysis of weather and climate” will be published in early 2010. I strongly encourage all researchers to read it because it expose the understanding that leads to ways of verifying, objectively the findings of climate science.
Professor Marcel Leroux passed away August 12, 2008, a year ago.
Bob Tisdale (09:29:39) :
Kevin Kilty: You wrote, “And, if Bob Tisdale, were on this post he’d undoubtedly…
I’ve been trying to use the “find on this page” option of the edit tab to help me see who is posting when I’m very late getting here, but it doesn’t seem to work consistently. Anyway by slowly going through the post, item by item, I saw that you were indeed here…
I can fully understand the oceans warming faster than cooling; the two mechanisms are different. Main warming mechanism is short wave radiation; main cooling is evaporation and long wave radiation.
“”” Kevin Kilty (05:20:53) :
Leif Svalgaard (23:13:44) :
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?
REPLY: Gosh Leif, I dunno. How’d that happen? Oceans = OBAHFC (One Big Assed Heat Flux Capacitor) 😉 – A
A somewhat pedantic point of physicists is that one refers to heat as energy during transfer only. If one looks at the oceans as being at a “dead state” temperature, then one does not see the oceans as a source, but rather only as a sink. In another context one must see the oceans as a source and the polar regions as a sink, howeve. I’d like to know, Leif, what was the context of this other thread? “””
“””A somewhat pedantic point of physicists is that one refers to heat as energy during transfer only. “””
I had to paste that twice; just to make sure I got it correctly.
As a practising physicist with more than 50 years of slogging away at it; this is my second introduction to this weird pedanticism; the first being whan Nasif started writing that on some of the threads here.
“Heat” is energy during transfer only; so what then is “light”. Well I know what it is; I work with it every day. Pedantically speaking it is the psychophysical response of the Human eye to received electromagnetic radiation in the single octave from about 400 to 800 nm wavelength.
So this distinguishes “light” from “heat”, since light exists ONLY after reception by the human eye (no not baboon eyes either); whereas according to Kevin and Nasif; and Nasif’s eminent Mentor, Heat does not exist in any storage mechanism; it is not emitted by anything, nor received by anything, but exists ephemerally during transit from source to sink. That puts it into the realm of particle physics almost, where the forces of nature are moderated by “exchange” particles that pass in a transitory fashion between particles to establish a foce between them. The standard classroom example is two ice skaters facing each other, and tossing a medicine ball (exchange particle) form one to other, and back thereby creating a repulsive force that drives them apart on the ice.
Now Kevin’s news will come as a big surprise to those few people who have bought solar thermal homes which have a basement pit full of rocks through which air warmed by the sun is passed during the day thereby warming the rocks up; so that at night they can pass air through those warmed rocks and use it to warm their house. I would say heat their house, but that would violate Kevin’s pedantic point of physics; that it isn’t heat unless it is in transit.
Well I have to disagree with both Kevin, and Nasif, after studying the subject for at least 50 years; “heat” if you must use it as a noun; ONLY exists in conjunction with real particulate matter; atoms and molecules; and it RESIDES in the mechanical kinetic energy of the random motions of those real matter particles. ONLY such real materials can have a “temperature”, which word has no meaning, absent real materials.
Incidently, the appropriate “exchange” particle of electromagnetism; one of the two natural forces with infinite range is the “photon”. Photons don’t exist inside anything; they aren’t real matter; they exist ONLY in transit from one particle to another in moderating the electromagentic force.
“Heat” on the other hand is NOT one of the exchange particles and exists only in real matter. Like warm rocks; or the earth’s oceans. That’s if you want to be physically pedantic of course.
George
3×2 (07:50:00) :
I have always been more than a little uncomfortable with applying “clean” physical laws to dynamic planet wide systems particularly ours.
I think that all systems obey the ‘clean laws’.
@ur momisugly Robert Wood (10:06:11) :
” The Sun can directly warm a body of water to teh depthe that sunlight is completely abosrbed, below whic it is dark and the oceans then only heat by conduction and convection and mixing. ”
Not to put too fine a point on it, but there is some heating as a result of volcanic activity – black smokers, island building, and the like. I’d be curious to know if anyone has a clue about that. Is it significant enough to take into account?
“”” oms (10:05:34) :
George E. Smith (09:38:43) :
Measuring the ocean’s heat content is even more troublesome than measurting the earth’s mean surface temperature, because that heat content problem is a three dimensional problem, whereas surface temperature is only two dimensions.
This is what profiling and objective mapping are for. And yes, it is a difficult problem.
Andybody who wants to measure the oceanic heat content of the earth is advised to buy a book on the theory of sampled data systems, and read it.
Some of the people working on this have read those books. Others are actively developing the theory. Why would you expect differently? “””
Well I’m glad to hear that OMS; so we don’t have to worry any more about Urban heat islands and other such peculiarities, that seem to upset computations such as GISStemp; but don’t seem to bother planet earth one iota; that’s wonderful news.
George E. Smith (10:28:02) :
There are urban heat islands in the middle of the ocean?
George E. Smith (10:18:42) :
…“heat” if you must use it as a noun; ONLY exists in conjunction with real particulate matter; atoms and molecules; and it RESIDES in the mechanical kinetic energy of the random motions of those real matter particles. ONLY such real materials can have a “temperature”, which word has no meaning, absent real materials.
Then, it is not “heat”, but kinetic energy (included in internal energy), which is not a trajectory quantity, but a state function.
So as you describe it is the same as saying “…and energy in transit (heat) RESIDES in the mechanical kinetic energy of the random motions…”
Sounds odd, isn’t it? I do not buy that.
“…. magnitude and phase confirm earlier observations that delivery of the energy to the ocean is rapid, thus eliminating the possibility of long time constants”
Wow, where have I heard that before?
I don’t want to bring this debate here again. I have explained this “thing” many times trying to be adhered to clear science.
For this reason, I won’t talk again on this issue; there are hundreds of scientific essays explaining and clarifying the physical theories from which you can find that I am correct.
I just want to express something very important for us all, who are incorrectly labeled like “skeptics”: We, as scientists and/engineers, who wish to restore the correct scientific methodology and truthful science, are not allowed to use wrongly the scientific terminology or to confound it. I told you this due to my personal experiences with AGWers.
I apologize if I have bothered to someone with true scientific concepts. Those are not my perceptions, but the perceptions of all physicists writing on heat, heat transfer, thermodynamics, physics, etc.
I forgot to say: Thanks, Anthony Watts and moderators, for your patience.