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Robust warming of the global upper ocean

Posted on 23 May 2010 by John Cook

Most of global warming goes into the ocean. Consequently, the amount of heat accumulating in the world's oceans is a vital cog in our understanding of climate. A number of teams across the world have performed analyses of ocean heat observations. While there's year-to-year differences between the various estimates, they all show essentially the same long-term trend. Now members from the various teams have combined their efforts into a single 'best estimate' of ocean heat (Lyman 2010). What they find is robust warming in the upper ocean over the 16 years from 1993 to 2008.

When reconstructing ocean heat content, the greatest source of uncertainty is biases in expendable bathythermograph (XBT) data. XBTs are dropped from ships and measure water temperature as they sink. One example of uncertainty is estimating how the rate at which the XBTs fall has changed over time as the instruments have subtly changed. This fall rate is used to work out the depth at which temperature is measured. The various teams working on the problem make their own choices on how to adjust for the various XBT biases. We can see the differences arising from these choices by overlaying the curves produced by each team. 

Upper ocean heat content anomaly
Figure 1: Ocean Heat Content anomaly from various teams. Ocean heat is calculated from 0 to 700 metres (Lyman 2010)
.

All the curves show significant warming of the global upper ocean  from 1993 to 2008. While there are differences in year-to-year variability, the long-term warming rates are broadly consistent. The various datasets were then combined into a 'best estimate' of ocean heat content including a comprehensive estimate of the total uncertainty. This is shown in Figure 2: the black line is the composite estimate of upper ocean heat content anomaly and the uncertainty marked in vertical black lines.

Upper ocean heat content anomaly
Figure 2: Ocean heat content anomaly curves from various teams (colour) and composite ocean heat content anomaly (black) (Lyman 2010).

In the same issue of Nature is a follow-up article, Global change: The ocean is warming, isn't it? (Trenberth 2010). Kevin Trenberth summarises the results of Lyman 2010 and gives a broader perspective. The general gist of his article is, loosely paraphrasing, "yes, the upper ocean is warming, fine, now where's my damn missing heat?!"

The most interesting feature in Trenberth's article is a comparison of upper ocean heat (the top 700 metres) versus ocean heat down to 2000 metres deep. In the following graph, the black line shows the 'best estimate' upper ocean heat curve from Lyman 2010 (the black line in Figure 2 above). The pink line is the long-term warming trend which averages 0.64 watts per square metre over the whole Earth. This is the global average, an indication of the planet's energy imbalance. The blue line is the observed rate of heat accumulating in the global ocean down to 2000 metres, calculated from von Schuckmann 2009.

Upper ocean heat content compared with ocean heat to 2000 metres
Figure 3: Changing heat content of the global ocean. Black curve is changes in upper ocean heat content (0 to 700 metres). Pink line is trend in upper ocean heat content. Blue line is trend in ocean heat content down to 2000 metres (Trenberth 2010).

When we look at ocean heat down to 2000 metres since 2003, the global ocean has been warming at a rate of 0.77 watts per square metre. When averaged over the entire Earth, the warming is 0.54 watts per square metre. This is a rough estimate of how much heat is building up from 2003 to 2008. Note that the blue trend is greater than the black line over the same period. This means that more heat is accumulating at greater depths than 700 metres.

In summary, the oceans show a robust warming trend from 1993 to 2008. The observed rate of warming has slowed somewhat compared to the 16 year trend but the ocean is still accumulating heat.

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Comments 51 to 78 out of 78:

  1. HR, I'm not assigning any causality or even forming conclusions, instead looking at what's available in the way of hints in publications such as those I cited. Recent Bottom Water Warming in the Pacific Ocean (pdf, full text) has a pretty good discussion of general factors controlling transfer of heat in the ocean, definitely worth a careful read. Be sure not to become beguiled or transfixed by the sentence "Abyssal cooling of about 0.02°C has been reported in the southwest Pacific Ocean...", heh!

    Ok, I lie, I'll allow myself one conclusion, namely that the classical understanding of vertical heat transfer in the ocean is appropriately conservative in the face of limited understanding of what's actually "going on down there" but needs and indeed is receiving some freshening (pun!).

    It'll be absolutely fabulous to see some instruments drifting around in the bottom half. Can we hold our breaths that long? I doubt it!
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  2. 51.doug_bostrom

    I wasn't accusing you of assigning casuality more this publication and the general assumption this is a AGW signal. It maybe but there seems a lot more to measure and explain before we say it is.
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  3. HR, no problem and I realized I sounded defensive as soon as I hit the "Submit" button. I'm trying to retrain myself to avoid signaling unfounded conclusions so was trying to be clear on that.

    OT but speaking of "Submit", I wonder what is the subconscious effect of that common term used on web interfaces, at sites sometimes featuring contention? Reminds me of the old New Yorker cartoon depicting a heavily ribboned and brassed military man at the wheel of his automobile, approaching a "Yield" sign and barking out "Never!"
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  4. HumanityRules #52

    Given that we can't model the observed 20th and 21st century warming without using CO2 as a parameter, it seems extremely likely that large scale observations of warming are also due to the same CO2 parameter. This is not mathematics, we can't provide logical proof - inductive proof is just how science works, and the global warming story is remarkably consistent for such a large poorly measured complex system. Just because some things are uncertain in the measurement system, it doesn't follow that everything is uncertain, which appears to me to be your argument.

    More generally I'm most unimpressed with the way that short term problems with the measurement model of ocean heat content are used by so called climate sceptics to try to draw strong conclusions about longer term climate implications, discarding much prior work on the topic in the process.
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  5. I know I'm going to be a bit boring by repeating the same thing, but I cannot resist to quote from the paper linked by Doug (thanks Doug, by the way):

    "The data from these repeat sections suggest that abyssal variations may contribute significantly to global heat, and hence sea level, budgets.
    To close ocean heat, sea level, and likely freshwater budgets on interannual time scales, the ocean below 2000 m must be much better sampled in space and time than it has been, or is likely to be, relying on repeat hydrography alone."

    Different paper, different people, similar conclusions, it's a travesty we cannot track the flow of energy through the climate system.
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  6. Riccardo #55

    Absolutely. The measurement model as it stands is indadequate to assess these heat budgets with a reasonable degree of certainty over a sufficiently long timescale. Until we have enough good quality data over a long enough timescale, this global heat balance stuff will not be good enough to make a substantial contribution to the state of the scientific consensus.
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  7. 54.kdkd

    "it seems extremely likely that large scale observations of warming are also due to the same CO2 parameter."

    I guess it's the 10 of the 16years of OHC showing no large scale observations of warming that makes me question this. It's the reduced uncertainty in the measurement system for the most recent period of no warming that further backs up my cautious approach. This isn't even necessarily a question of if AGW is occuring but could just be the magnitude.
    Everybody seems fixed on finding the missing heat rather than considering whether we should reduce our overall estimate of the build up of energy in the system based on these observations. Given the singularity of this approach there's likely only one possible outcome somebody, somehow will find the missing heat.
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  8. From the Pielke Snr website this was Josh Willis assessment of Johnson most recent paper on deep ocean warming
    "They looked at the prospect of deep warming on decadal time scales using the sparse, but highly accurate repeat hydrographic sections and found that below 3000 m in the global oceans, and below 1000 m in the southern ocean, the ocean is taking up an energy equivalent of about a 0.1 W/m^2 energy imbalance at the top of the atmosphere. So while this is significant, it suggests to me at least that the deep ocean is probably not taking up a bunch of heat really rapidly and the traditional idea that most of the action is in the upper several hundred meters is probably going to hold up."
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  9. HumanityRules #57

    There's certainly something wrong somewhere. Your final comments are a mis-statement of the scientific process. If someone can find strong evidence that the missing heat doesn't actually exist then that will make their career. Meanwhile the surface observations are what are used to make the (to date rather conservative) IPCC & co predictions, and the heat imbalance model is a bit of a side show to the main game. Much as some people would like it to be central. However the uncertainties relative to the other things that are measured better, and easier to measure are so high this won't happen for a while.

    What's the uncertainty on the 0.1 W/m2 term by the way, i.e. ± how much?
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  10. HR #57 #58, kdkd #59

    If Josh Willis' 0.1W/sq.m sequestered in the deep oceans (below 1000m) is correct, and the upper levels (down to 900m)are showing flat OHC from Argo post 2004, then Dr Trenberth's 0.9W/sq.m TOA imbalance is *nine* times the increase in OHC. Both cannot be right when there is no other feasible heat storage than the oceans.

    The 0.1 W/sq.m is small enough to be from other sources like undersea volcanoes or geothermal (warm bottom) sources.

    The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing. Try heating your bath with a radiant heater held above the surface or from warm air in a room. SW penetrates about 300m into water and LW a few millimeters. An immersion heater is a different story. Undersea volcanoes or geothermal heating would be much more efficient in heat transfer terms.

    Or the other 8/9ths of Dr Trenberth's heat could simply be lost to space where the heat sink is at -273 degC.

    The above 60 posts show that warming of the upper oceans is not 'Robust' at all. BP has got it pretty right in his application of the first law, and the conclusion that the large OHC increases prior to 2004 are offset errors in the XBT-Argo transition is much more 'Robust' I would suggest.
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  11. Ken Lambert:

    The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing.

    You'll need to develop that assertion into an explanation better than what others practicing in the field have done before you're convincing. You do realize that, right?
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  12. Ken Lambert at 23:46 PM on 26 May, 2010

    "The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing."

    Nope. An unconvincing variety of "common sense" doesn't "trump" a century of understanding of the thermodynamics of radiative heat transfer!

    Remember that for each 10^22 joules of energy added to the top 700 metres of the oceans, this region of the ocean (top 700 metres) warms by ~ 0.01 oC [*]. Therefore year on year variation of upper ocean heat content is very difficult to measure and yearly averaged measures of ocean heat content have a considerable associated error (as is apparent in the error bars in the data in the figures in the top post). As with all measurements where yearly data points have large associated errors, longer term measures are more robust than short term measures.

    So it's possible that the calibration errors in ARGO floats haven't been completely eliminated and we aren't quite measuring the upper oceans reliably. It's also possible that some of the heat may be in regions of the oceans (greater depths) and partly escaped detection. it's also possible that for a short period there hasn't been a significant radiative imbalance (e.g. due to a particular coincidence of atmospheric effects), and so some of the heat wasn't missing at all (we'll get it as an "added chunk" as atmospheric fluctuations shift in the other direction).

    We have reasonable evidence that sea level rise slowed for a couple of years around 2006-2008, but that the longer term trend of sea level rise has pretty much caught up. The sea level rise in recent years can't be fully accounted for from knowledge of land ice melt, and efforts to "close the sea level budget" for these short periods require some thermal expansion (enhanced ocean heat) contribution [**].

    So there are some interesting uncertainties to be resolved for this very short period of time. No doubt in the next few years these uncertainties will be resolved. However as with all areas of science, one doesn't choose one area of uncertainty, select a particular set of data, and then assume that encasing this within a bit of arithmetic defines absolutely what's happening in the natural world.
    -------------------------------

    [*] In case anyone wants to check my sums:

    surface area of oceans: 3.61 x 10^14 m^2

    volume of top 700 metres: 3.61 x 10^14 x 700 =
    2.57 x 10^17 m^3 = 2.57 x 10^20 litres

    weight of this seawater: 2.57 x 10^20 x 1.03 kg (density correction)

    it requires 4186 joules to warm 1 kg of water by 1 oC

    raising the temperature of the top 700 metres of the oceans by 0.01 oC requires 2.56 x 10^20 x 4186 x 0.01 = 1.07 x 10^22 joules.....



    [**] recently reviewed here:

    A. Cazenave and W. Llovel (2009)Contemporary Sea Level Rise Annual Review of Marine Science 2, 145-173
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  13. John, have you considered updating the ocean cooling page?
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  14. Chris #62

    I checked your sums and they are correct. The next question is what is the accuracy of measurement of water temperature by Argo??

    Noting that E22 Joules = 100E20 Joules and Dr Trenberth's 0.9 W/sq.m imbalance at TOA equals 145E20 Joules/year - if all this heat was absorbed in the top 700m of the oceans, then this would equal 0.0145degC temperature rise.

    Is this rise observed and with what accuracy??

    You might explain why there could be a "global short period where there hasn't been a significant radiative imbalance (e.g. due to a particular coincidence of atmospheric effects)". CO2GHG theorizes a relationship of forcing imbalance which is only dependent on log CO2 concentration. Is there any data to suggest a smothering of this CO2GHG forcing by increased cooling effects over a transient period which operates globally?
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  15. Ken you can check on accuracy and many other fascinating details of the ARGO system and other systemshere (PDF, "World Ocean Database 2009).

    Also, TOA balance discussions could probably benefit from integration of information found in this article by Trenberth et al, 2009.
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  16. Ken Lambert at 00:07 AM on 28 May, 2010
    "You might explain why there could be a "global short period where there hasn't been a significant radiative imbalance (e.g. due to a particular coincidence of atmospheric effects)". CO2GHG theorizes a relationship of forcing imbalance which is only dependent on log CO2 concentration. Is there any data to suggest a smothering of this CO2GHG forcing by increased cooling effects over a transient period which operates globally?"


    I don't think that's really correct Ken. If by "CO2GHG" you mean the Earth temperature response to enhanced [CO2], then this doesn't really "theorizes a relationship of forcing imbalance which is only dependent on log CO2 concentration". It "theorizes" that there is a contribution to forcing that depends on the logarithm of the proportion by which [CO2] changes. But it certainly doesn't presume that the forcing from enhanced greenhouse is the only contribution to forcing. It's obvious that that isn't the case. By considering the forcing from enhanced [CO2] we don't then decide to ignore all the other forcings (solar, atmsopheric aerosols, clouds etc.) that contribute to radiative forcing, and which modulate the effects of changes in [CO2].

    So to answer your question, we know, for example that during the last 6-7 years there has been a steady reduction in the solar output which opposes the [CO2] forcing (not by much, but empirical analysis shows it is enough to effectively counter the expected increase in surface temperature from the [CO2] forcing during the solar downswing). We know that following large volcanic eruptions the forcing from [CO2] can be completely negated for a year or two. It's possible that a short term fluctuation in cloud cover (that might relate to ocean circulation fluctuations) could significantly modulate the [CO2]-induced radiative forcing for some period.

    Clearly there hasn't been large volcanic eruptions in recent years. I suspect that there likely hasn't been major variations in cloud cover either (we could investigate this, but I expect it would have been reported by now). We know that the solar effect is applicable to the period in question.

    The point is that our understanding of the radiative response to enhanced [CO2] doesn't require that there is some absolutely constant radiaive imbalance at the top of the atmosphere. It fluctuates up and down stochastically and in response to non-stochastic variation (like that incolving the solar cycle). Averaged over longish periods the stochastic variability averages out and the average forcing will apply. Strictly speaking, the theory of greenhouse gas forcing relates to the effects on Earth surface temperature once the latter has come to equilibrium with the forcing. The temporal trajectory by which it get's there is a different kettle of fish altogether, and periods of apparent temperature stasis or cooling, apparent slowdowns in sea level changes and ocean heat uptake, etc. aren't unexpected.
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  17. Doug #65 Chris #66

    Similar information is repeated in Dr Trenberth's Aug09 paper:

    http://www.cgd.ucar.edu/cas/Trenberth/trenberth.papers/EnergyDiagnostics09final2.pdf

    which I have oft quoted in these blogs.

    The relevant Fig 4 of this paper shown how the TOA imbalance of 0.9W/sq.m is derived.

    Note that the main warming components are CO2, about 1.66W/sq.m and other GHG (1.0 W/sq.m) and the main cooling effects are surface, direct and cloud albedo. Solar is minimized at 0.12W/sq.m giving an overall net AG forcing imbalance of 1.6W/sq.m.

    Dr Trenberth then shows the Net Responses of the Earth system as -2.8W/sq.m (radiative feedback) and WV and ice albedo as +2.1W/sq.m giving a net response of -(minus)0.7W/sq.m. (The -2.8W/sq.m is calculated from S-B for a temperature rise of 0.75degC at a radiating temperature of 255degK. This is proportional to T^4.)

    The TOA imbalance is net AG (+1.6) and net response (-0.7) to give 0.9W/sq.m total net imbalance.

    Chris, the Solar forcing is only 0.12W/sq.m and we know that the 11 year cycle gives an incoming variation of about 0.25W/sq.m from top to bottom - therefore this is nowhere near enough to offset the postulated 0.9W/sq.m of net positive imbalance.

    If you look at the CERES satellite data there is a +6.4 W/sq.m TOA imbalance - which is impossible; so again we have an offset error and BP's low accuracy but high precision.

    In fact if you look at Doug's reference: http://content.imamu.edu.sa/Scholars/it/net/trenbert.pdf
    the absolute values of the components are all over the place - so only year to year differences make sense.

    If you go back to BP's post #30 or #36 (I think) he gives the last 10 years satellite chart and there are no significant year to year trends showing anything near negating the 0.9W/sq.m imbalance at TOA.

    Clouds and aerosols could be the most poorly understood, modelled and measured, however Dr Trenberth claims that HIRS is measuring to +/-1% which is +/-0.5W/sq.m and again - no big differences year to year.

    And of course the OHC seems flat since 2004 by Argo analysis.

    Conclusion: The 0.9W/sq.m imbalance might be much less over the last 6 years at least and the major culprits are Log CO2, Log 'other GHG', WV+Ice albedo feedbacks, or Surface, Direct and Cloud albedo. Clearly less warming, or more cooling or combinations of both.
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  18. PaulK, It seems we all share Trenberth's frustrations. Poor Trenberth has been scrutinizing this matter for decades now, always struggling with the sort of problems you detail. The thing I find most astonishing about his 2010 review are the enduringly paltry choices he has for obtaining primary data, choices that have problems known for 20 years or more and have gone largely unaddressed, or at least have not enjoyed concerted attention on the part of folks assembling mission objectives.

    We've ignored the requirement for better instrumentation, the price of which is vanishingly small compared to what we collectively spend on really important things, such as hair gel for us guys and eyeliner for the ladies.

    We can't just throw money into instrumentation randomly, but in fact we do have a reasonably good idea of what we want to measure. Venus has a dedicated climate orbiter on the way with the primary mission of taking a close look at various aspects of radiation there. Back here-- where we live-- we mostly use instruments glued onto orbiters as afterthoughts.

    As I mentioned earlier there are plans to intensify deep ocean measurements, good, but it's still a puzzle to me as to why we're -planning- data collection now as opposed to -analyzing- data we've already collected.

    Really, our thinking about money and opportunity costs is quite incoherent.
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  19. Ken #67

    The one thing you always ignore in raising this argument is the importance of measurement error, although you will always report the bottom end of the uncertainty to try and support an "AGW isn't terribly important" position. An explicit acknowledgment of the size of error terms, and accounting for the full range of possible values (not cherry picking the range at which you will consider) is important.

    The other area your argument is deficient, which we've been through before is that you will only consider data at very short time durations. In order to improve the validity of your argument you need to consider longer time durations which would fit the definition of "climate". At the moment, you're really looking at "weather" and claiming that it's climate.
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  20. kdkd #69

    Is 16 years of "Robust" global upper ocean warming - which is the subject of this blog; regarded as climate or weather kdkd?

    If it is climate, then BP and I have illustrated that the large jumps in OHC before 2004 are calibration offsets of the XBT-Argo transition, and most probably illusory.

    If it is weather 'noise' then the same conclusion applies - not 'robust' but illusory.
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  21. Ken,

    We've been through this to death elsewhere. You maintain that the global heat balance is well enough understood to supersede all other global warming indicators. I maintain that the global heat balance is one of the least understood parts of the system, and the measurement uncertainties are why it can't be used to discard all the other evidence for AGW. At the end of the day what is required is a consistent story that is scientifically robust. The uncertainties in the global heat balance record that are inconsustent with
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  22. #60 Ken Lambert at 23:46 PM on 26 May, 2010
    The mechanism of heat transfer to the oceans from the atmosphere has always been unconvincing

    You are right. Downwelling can only occur close to the ice edge where sea surface temperature is pretty constant (determined by freezing point of seawater). On top of that water salinity at surface has to be higher than at bottom and/or its potential temperature has to be lower. It is easy to see that with no additional heating from below bottom water becomes saturated sooner or later in both respects. If that happens, circulation is halted.

    Thermal conductivity of water is rater low (0.58 W m-1 K-1). It means that with 20 K temperature difference between surface and water at a depth of 4000 m heat transfer by conduction is only 3 mW m-2. It takes more than 150 kyear to heat up the abyss by 1 K this way.

    On the other hand average heat flow from oceanic crust is 100 mW m-1 and at some places it can be as high as 350 mW m-1



    For geothermal heating it takes only 5000 years to raise ocean temperature by 1 K. BTW, there is about the order of magnitude correspondence between this figure and alleged ocean turnaround time.
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  23. Regarding modelling temperatures in the atmosphere, re: "#54 kdkd at 16:59 PM on 26 May, 2010
    HumanityRules #52

    ......Given that we can't model the observed 20th and 21st century warming without using CO2 as a parameter, it seems extremely likely that large scale observations of warming are also due to the same CO2 parameter........"

    Apparently not all the available data has been incorporated into the paradigm. This paper by Dr. Nicholas Scafetta (at http://arxiv.org/abs/1005.4639) takes a further look at variabilities in the climate caused by various resonances between the orbits of the planets, the sun, and the moon.

    Abstract: We investigate whether or not the decadal and multi-decadal climate oscillations have an astronomical origin. Several global surface temperature records since 1850 and records deduced from the orbits of the planets present very similar power spectra. Eleven frequencies with period between 5 and 100 years closely correspond in the two records. Among them, large climate oscillations with peak-to-trough amplitude of about 0.1 degC and 0.25 deg$, and periods of about 20 and 60 years, respectively, are synchronized to the orbital periods of Jupiter and Saturn. Schwabe and Hale solar cycles are also visible in the temperature records. A 9.1-year cycle is synchronized to the Moon’s orbital cycles. A phenomenological model based on these astronomical cycles can be used to well reconstruct the temperature oscillations since 1850 and to make partial forecasts for the 21st century. It is found that at least 60% of the global warming observed since 1970 has been induced by the combined effect of the above natural climate oscillations. The artial forecast indicates that climate may stabilize or cool until 2030-2040. Possible physical mechanisms are qualitatively discussed with an emphasis on the phenomenon of collective synchronization of coupled oscillators."

    All of these astronomical resonances have effects akin to the tides caused by the sun and the moon and can cause changes in the transfer of radiation from the sun. Given that the temperature reconstruction gives a pretty remarkable fit to the measured variations in the temperature record, something no GHG climate model does, the results show me that at the very least all of the mainstream forecasts of temperature and CO2 are missing a major portion of the climate equation
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  24. PhilC, to my untrained eye Scafetta appears to be throwing things against the wall, hoping something will stick.

    Previously Scafetta has said We estimate that the sun contributed as much as 45–50% of the 1900–2000 global warming, and 25–35% of the 1980–2000 global warming. These results, while confirming that anthropogenic-added climate forcing might have progressively played a dominant role in climate change during the last century, also suggest that the solar impact on climate change during the same period is significantly stronger than what some theoretical models have predicted. Problems with this assertion were discussed at Real Climate.

    In another paper, Scafetta says We find good correspondence between global temperature and solar induced temperature curves during the pre-industrial period such as the cooling periods occurring during the Maunder Minimum (1645–1715) and the Dalton Minimum (1795–1825). The sun might have contributed approximately 50% of the observed global warming since 1900 This paper was also critiqued at Real Climate

    At least those two papers had something in common. Now Scafetta is trying something else entirely? But what about the previous research? Is it inoperative now? Is there something new under the Sun?
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  25. Delving into Scafetta's latest paper, we immediately find a dubious assertion:

    The existence of a 60-year natural cycle in the climate system, which is clearly proven in multiple studies and herein in Figures 2, 6, 10 and 12, indicates that the AGWT promoted by the IPCC [2007], which claims that 100% of the global warming observed since 1970 is anthropogenic, is erroneous.

    Does the IPCC claim that 100% of warming observed since 1970 is anthropogenic?

    Here's what the IPCC 2007 report actually says:

    Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic GHG concentrations. 7 It is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antarctica) (Figure SPM.4). {2.4}

    Not even close to a flat 100%, not by the most liberal interpretation. So either Scafetta can't read, has not read the IPCC material he references, or is resorting to rhetorical hyperbole, something unwelcome in a scientific paper. No matter as long as we don't care what's true or false, Scafetta has a hypothesis. Or does he?

    The planets, in particular Jupiter and Saturn, with their movement around the Sun give origin to large gravitational and magnetic oscillations that cause the solar system to vibrate. These vibrations have the same frequencies of the planetary orbits. The vibrations of the solar system can be directly or indirectly felt by the climate system and can cause it to oscillate with those same frequencies.

    More specific physical mechanisms involved in the process include gravitational tidal forces, spin orbit transfer phenomena and magnetic perturbations (the jovian planets have large magnetic fields that interact with the solar plasma and with the magnetic field of the Earth). These gravitational and magnetic forces act as external forcings of the solar dynamo, of the solar wind and of the Earth-Moon system and may modulate both solar dynamics and, directly or indirectly, through the Sun, the climate of the Earth.


    So what's the mechanism?

    Later:

    In conclusion, data analysis indicates that current general circulation climate models are missing fundamental mechanisms that have their physical origin and ultimate justification in astronomical phenomena, and in interplanetary and solar-planetary interaction physics.

    In sum, we're asked to accept as certainty an indication of a previously unknown cyclical mechanism influencing climate, this cyclic process being derived from a fairly scanty physical record and an elaborate compound astronomical process. More, despite there being no known actual physical process describing how this mechanism may function, this mystery is "fundamental" and should be included in GCM's or they're incomplete.

    All this coming from somebody who for whatever reason was unable to accurately describe what the IPCC actually has said regarding the behavior of the climate.

    What would happen if the IPCC included work of this sort in WG1? Would anybody complain? Nah, surely not.
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    Moderator Response: Better topic thread for discussion of this is Models are unreliable
  26. But this paper hasnt actually been published yet has it? It looks rather like it needs some reviewing (unless of course it is for E&E).
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  27. BP #72

    Interesting Graph of geothermal heat flow from the global ocean bottom BP.

    If I could extrapolate your numbers:

    Heat energy to heat all the oceans by 1.0 degK:

    Mass of global ocean water 1.435E21 kG x Specific Heat 4.18 kJ/kG/degK = 6.0E21 kJ = 6.0E24 Joules.

    If this 1 degK rise takes 5000 years then the geothermal heat energy added per year is: 6.0E24/5000 = 1.2E21 Joules/year.

    Willis finds the equivalent of 0.1 W/sq.m of energy sequestered in the deep oceans (below 700m) which equals 1.61E21 Joules. (Remember Trenberth's 0.9W/sq.m TOA = 145E20 Joules/year = 14.5E21 Joules/year)

    Average ocean depth is 3700m so the proportion of geothermal heat energy added below 700m is 3000/3700 x 1.2E21 = 0.97E21 Joules/year.

    We seem to have found 0.97E21 of Willis' 1.61E21 Joules/year from BP's oceanic crust geothermal heat; which is just over 60%.

    I don't know if this crustal heat includes undersea volcanoes - perhaps BP could answer that.

    Either way, if BP's numbers are right, the prospect of heat emanating from the ocean bottom (immersion heating) certainly is of the right order of magnitude and a feasible transfer mechanism to explain a large chunk of Willis' 0.1 W/sq.m deep ocean warming.
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  28. Ken Lambert at 23:26 PM on 10 June, 2010

    You persist in pursuing an illogic argument Ken. If you argument is to have any merit you should produce some evidence that the geothermal heat flux has miraculously accelerated hugely (i.e. doubled) during the last couple of decades during which we've seen an apparent large increase in deep ocean heat.

    This has been explained in response to your previous pursuit of this odd argument here, and here.
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