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## Climate time lag

#### Posted on 8 July 2009 by John Cook

The previous post on CO2/Temperature correlation sparked some interesting comments on climate time lag. Unfortunately, the discussion went pear shaped with some ideological anti-intellectualism and things got a little bitchy after that. Nevertheless, climate time lag is an important subject that deserves more attention. Several metaphors were invoked in an effort to explain the phenomenon including stove hot plates and warming baths. However, I find the best way to understand climate time lag is a direct look at the science.

Our climate receives its energy from the sun. The amount of energy the planet absorbs from the sun is calculated from this equation:

### Incoming Energy Flux= πR2S(1-A)

R is the radius of the earth, S (the solar constant) is the energy flux from the sun and A is the Earth's albedo - around 30% of sunlight is reflected back to space. The earth also radiates energy into space. The amount of energy emitted is a function of its temperature:

### Outgoing Energy Flux = 4πR2εσT4

σ is Boltzmann's constant, T is the absolute temperature in degrees Kelvin and ε is the average emissivity of the earth. Emissivity is a measure of how efficiently the earth radiates energy, between 0 and 1. A blackbody has an emissivity of 1. Greenhouse gases lower the earth's emissivity. When the climate is in equilibrium, energy in equals the energy out.

### S(1-A) = 4εσT4

What happens if the sun warms (solar constant S increases) then maintains a sustained peak? This is what occured in the early 20th century when solar levels rose then plateaued at a hotter state in the 1950's. The radiative forcing from the warming sun is not particularly large - between 0.17 W/m2 (Wang 2005) to 0.23 W/m2 (Krivova 2007) since the Maunder Minimum. Nevertheless, let's assume for the sake of argument that there is some amplifying effect (perhaps the cosmic ray effect on clouds) so that the warming sun has a substantial effect on global temperature.

When the sun warms, initially more solar energy is coming in than is radiating back out. The earth accumulates heat and it's temperature rises. As the earth warms, the amount of energy radiating back out to space increases. Eventually, the energy out matches the incoming solar energy and the planet is in equilibrium again. The time lag is how long it takes climate to return to equilibrium.

How long does the climate take to return to equilibrium? The lag is a function of climate sensitivity. The more sensitive climate is, the longer the lag. Hansen 2005 estimates the climate lag time is between 25 to 50 years.

How would climate have responded to the solar levels maxing out in the 50's? For the next few decades after the 50's, the radiative imbalance would've gradually decreased until the climate reached radiative equilibrium around the late 80's (give or take a decade). So how has our planet's radiative imbalance evolved over the latter 20th century?

Figure 1: net radiation flux at the top of the atmosphere (Hansen 2005).

Hansen 2005 finds that the net radiative imbalance has steadily increased over the 20th century. There is no indication that the climate is heading towards equilibrium - quite the contrary. This is confirmed by satellite measurements of energy flux at the top of the atmosphere:

Figure 2: Global ocean heat storage (blue) against global net flux anomalies (Wong 2005).

The climate is not heading towards equilibrium. Rather, the radiative imbalance is increasing with the climate steadily receiving more energy than it is radiating back out into space. And this is where the true significance of climate time lag lies. Even if the radiative imbalance were to level off at its current rate of around 0.85W/m2, it would take several decades for the climate to return to radiative equilibrium. Based on this climate lag, Hansen 2005 calculates there is still 0.6°C warming still "in the pipeline".

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Comments 51 to 100 out of 388:

1. Chris, Thank you for the additional detail on the Svensmark paper. "A rather fatal flaw with the cosmic ray flux (CRF) cloud/climate hypothesis is that the straightforward natural experiments in which the CRF varies by up to 20% through the 11 year solar cycle, or undergoes dramatic short lived reductions again up to around 20% in so-called Forbush events, shows no significant cloud response whatsoever….." I don't know why you keep making this statement, but it is inaccurate. From Sloan & Wolfendale 2008 "we estimate that less than 23%, at the 95% confidence level, of *the 11 year cycle change in the globally averaged cloud cover observed in solar cycle 22* is due to the change in the rate of ionization from the solar modulation of cosmic rays." http://www.iop.org/EJ/abstract/1748-9326/3/2/024001/ From the above, we can clearly see that there is an 11 year change in globally averaged cloud cover that (more or less) follows the solar cycle. To keep asserting the contrary is to ignore the evidence. Likewise, here is some evidence that cloud cover is affected by Forbush events Harrison R.G. & D.B. Stephenson, Proc. Roy. Soc. A, doi:10.1098/rspa.2005.1628, 2006 I think that you seem to be misunderstanding the state of the science here. "Shaviv and Svensmark don't publish this sort of stuff in the peer-reviewed scientic literature since you generally have to present scientifically and logically robust arguments with proper data, in science journals. Obviously one can say whatever one likes on one's website." While it is true that this particular response wasn't published, this leaves the impression that they can't publish their ideas. Both gentlemen's papers have been pretty widely cited, and while the overall theory is still debatable, the evidence for it is **substantially** better than you are attempting to present it as. That doesn't mean that it will turn out to be an accurate theory, but the idea that they cannot make logical arguments is not true. Thank you for the Erlykin paper, that is interesting stuff. BTW, how familiar are you with Krisjannson's paper, I can't figure out how he derived his conclusions. If you look at his actual graphs, they appear to give quite high correlation btw CRF and the cloud measurements, but he somehow comes to the conclusion that they are not closely correlated at all. Cheers, :)
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2. re 47 Most of the ocean mass increase occurred in 2004/2005. What I said was let's assume that is real and not some artifact of JASON altimetry.
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3. Do cloud affect climate? Without a doubt. The ISCCP-FD reconstruction shows decling cloud cover to 1998 and increasing cloud cover since. This can be seen on Professor Ole Humlum's website. A great source for up to date climate data. http://www.climate4you.com/ClimateAndClouds.htm In the climatically important equatorial zone. Both high and low cloud cover decreased to 1998 and have increased since then explaining some of the global heat trends - particularly the perplexing mystery of the lost heat since 1998. I also note an updated sea level graph on the ocean page graph showing a decline in annual sea level since 1998. And before anyone quibbles - check the ocean heat storage in Figure 2 above. Now I am confused - it is based on the (gold standard)University of Colorado data but looks entirely different because it averages the 10 day readings over a year. I am now wondering whether this has something to do with the hydrological cycle. A global increase in water vapour and rainfall - driven by higher sea surface temperature after the mid 1970's. A problem for Ron (lateron - for those unfamiliar with Australian colloquialism - Blind Freddy has offered to lead a seminar). Ah complexity - thy name is climate science. Is there a connection of cloud with the 11 year solar cycle? All I know is that clouds have changed and that there is a long term correlation of cosmogenic isotopes and global temperature. If clouds change back around 2024, I will be surer of a cloud cover and a cosmic connection to the Pacific Decadal Oscillation and multi-decadal ENSO modulation. I am pretty sure there are 50, 1500 and 100,000 year (approximately) climate cycles.
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4. Actually, I was confused - the graph shows annual change in sea level and not mean sea level. It shows the rate of change declining declining since 1998 - there should be a law against people who torture data. Cheers Robbo
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5. re #51 ONE: Solar cycle – cloud response There isn't a robust relationship between the solar cycle and cloud response. There was an apparent relationship within solar cycle 22 (which is what Wolfendale and Sloan were addressing), but this relationship completely breaks down in the following cycle, and the recalibration of the ISCCP data (partly in response to artefacts in the satellite viewing geometry over which there still seems to be some concern; e.g. [*]) makes this apparent correlation smaller still [**]. You can see the mismatch between the cloud data and the solar cycle over the full record by sampling the ISCCP data from its repository: http://isccp.giss.nasa.gov/index.html (see Part 7 for low, medium and high level clouds) The bit of the abstract you quoted from the Wolfendale Sloan paper doesn't mean that 23% of low level cloud – solar cycle relationship (which is only apparent for solar cycle 22 and has been recalibrated anyway!) is due to the CRF, nor that the clouds necessarily respond in a cyclical manner in response to the solar cycle. It just means that the statistical relationship between the solar trend through cycle 22 and the cloud trend through cycle 22 has less than 23% that could "belong" to any CRF component. The meaning is clearer if one quotes from the body of the paper:
"From this it is deduced that less than 23% of the distribution, at the 95% confidence level, belongs to the part correlated with the CR modulation and more than 77% belongs to the other sources correlated to solar activity but not directly to the change in ionization rate. These limits are incompatible with a large part of the change in the LCC during solar cycle 22 being produced by a change in ionization and so they do not corroborate the hypothesis of such a change proposed in [1, 2]. The correlation seen in figures 1 and 2, if real, must be due to an effect, other than ionization, which is correlated with solar activity."
TWO: Web site advocacy vs scientific literature I said:
"Shaviv and Svensmark don't publish this sort of stuff in the peer-reviewed scientic literature since you generally have to present scientifically and logically robust arguments with proper data, in science journals. Obviously one can say whatever one likes on one's website."
you said:
"While it is true that this particular response wasn't published, this leaves the impression that they can't publish their ideas."
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6. Loads of thanks! I've been trying to understand the warming in the pipeline for some time without success. Thanks to this article I think I get the picture. It also helps me to understand the "simple model" article at RC (http://www.realclimate.org/index.php/archives/2007/04/learning-from-a-simple-model/). Thanks a lot!!!
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8. shawnet, yes, O.K., but the preprint you've described is another example of evidence in the scientific literature (to be!) of a lack of significant causal relationship between the cosmic ray flux (CRF) variation and cloud/temperature variation. I'm happy that you're directing our attention to the science rather than the dreadful website you linked to earlier on this thread. We can look at the preprint in more detail... downloadable from here: http://arxiv.org/abs/0906.4442 [A.D.Erlykin, G.Gyalai, K.Kudela, T.Sloan, A.W.Wolfendale On the correlation between cosmic ray intensity and cloud cover] The following points can be made: 1.There isn't a robust correlation between the solar cycle and the ISCCP cloud data. That can be confirmed by inspection of the ISCCP data I linked to above (see post #55). There is a correlation between the solar cycle and low level clouds through cycle 22, after which this correlation breaks down. Erlykin describe a moderate correlation coefficient (0.54) between solar cycle and low clouds through cycle 22 but this is only 0.24 through cycle 23 which is an very low correlation. Erlykin present data up to 2005. If this is extended to 2008 (see ISCCP web site link in post #55), the correlation is even worse. 2. Erlykin address "the correlation between cosmic ray intensity and cloud cover". The conclusion is that this correlation is moderate in cycle 22, but effectively discorrelated in solar cycle 23. In all cases any correlation is shown not to be causal. In other words (according to Erlykin), any apparent correlation is not the result of a CRF effect on clouds but is (if the correlation is true) due to the solar irradiance changes through the solar cycle. e.g. Erlykin et al conclude:
"the reduction of CR intensity coincident with the reduction of LCC is therefore by no means evidence of the causal connection between these two phenomena – they correlate with each other due to their common origin - the change of solar irradiance at the Earth."
and
"We argue that the positive correlation of CR and LCC found in Svensmark and Friis-Christensen, (1997) and Palle Bago and Butler, (2000) is not evidence for a causal connection between them, but the consequence of a parallel influence of the common source - the solar activity on CR from one side and CC the other."
3. Erlykin make a number of analyses of the possible causal contribution of CRF on low level cloud cover during solar cycle 22 (where there is a bit of a correlation with the solar cycle). Within a model where CRF are responsible for a fraction of the low level cloud change and CRF is the only cause of this fraction (the Shaviv model; Svensmark might or might not agree) they can determine a value of the fraction of low level clouds caused by changes in CRF. This is close to zero:
"This shows that the most likely fraction of LCC (low cloud cover) connected with CR (cosmic rays), which can be derived from expression (3), does not exceed 2% around X = 1."
and so on…the data and analyses taken at fasce value strongly support the conclusion that clouds, whether low level or whatever, do not respond signifcantly to changes in the CRF, and any apparent corelations observed (in solar cycle 22) are not causal. The likely source of any apparent correlations is the efects of solar irradiance changes on atmospheric and surface temperature. That seems entirely consistent with a vast amount of other science in the scientific literature. 4. General point: You suggest that "Just because you disagree with Svensmark and Shaviv doesn't mean that they don't make logical arguments (even on their blogs)." But again that misses the point. I don't particularly disagree with what Shaviv and Svensmark say in their peer-reviewed scientific publications.. I disagree with the misrepresentational advocacy and false arguments on their websites (and Svensmark dismal book for that matter). I gave a couple of examples in relation to the Shaviv web site you urled (see my post #50)…the Svensmark web report I urled in post #50 is dripping with false "arguments". That's what I disagree with shawnet – rubbish on dodgy websites created to misrepresent the science. 5. Another general point. There's lots of evidence of solar contributions to changes in climate in the past. It so happens that there has been little secular change in the solar outputs since 1958 (when these parameters started to me assessed in great detail), and the very marked warming of the past 30-odd years almost certainly has a negligible contribution from solar changes (despite the unsupported assertions on the dreary website you linked to in an earlier post). The solar contributions to climate changes in the past can generally be understood in relation to solar irradiance changes. Since the CRF changes generally correlate strongly with the solar irradiance changes (outwith Forbush events and the like), it’s easy for scurrilous "arguments" for solar irradiance chamges to be interpreted in terms of CRF changes (Svensmark does this on his website I urled).
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9. G'day, The PDO certainly has a correlation with global surface temperature. A cool mode to 1975 and a warm mode to 1998. The biological and physical chemical indications are that the PDO switched to a cool mode post 1999. The parallel with surface temperature is unmistakable. Although, I think it is a mistake to assume that the PDO is a cause of climate change rather than a co-variant. The PDO is associated with decadal modulation of ENSO. More intense and frequent El Niño in a warm mode and more intense and frequent La Niña in a cool mode. This suggests one mechanism for planetary warming and cooling. There are a couple of questions. Is the PDO real? It is certainly clearly evident in the sea surface temperature record in the latter half of last century. Before that – the available data all has wide margins of error. I think the most compelling argument for a natural origin is that is does seem to have conclusively switched to a cool mode. The cause of the PDO is deeply uncertain. The physical systems involved suggest that increases and decreases in shortwave radiation hitting the ocean surface heating could be the underlying cause if this varies on multi-decadal timescales. The ISCCP cloud cover record suggests that this is a possibility – although the period of record (and perhaps uncertainties in the data) are insufficient to be anywhere near conclusive. The periodicity of the PDO is certainly not explained by the 11 year solar cycle. The 22 year polar reversal cycle a more likely candidate. See this 1995 paper for an explanation. The 22 year cycle gives 11 years of peak magnetic activity and 11 years of subdued magnetic activity. Could this interact with the physical systems of the planet to produce changes with a 25 year harmonic? Interesting speculation. http://dawn.ucla.edu/personnel/russell/papers/731/731index.htm The heliospheric magnetic variation may be more important or the solar modulation parameter of Usoskin. These certainly did not peak in 1960 along with sunspot number. This all remains speculative and arguments about the non correlation of a particular metric misses the point. If the theory doesn’t fit the data – the theory needs revision. The current global warming debate finds certainty where there is precious little to be had. We talk about 50 years or less of reasonably accurate data on a few metric as if that could provide proof in such a complex system. We talk about reconstructions going back millions of years as if there is a precision in the results sufficient to mirror the precision of instrumental results. We have forgotten all of our ‘science of science’ and instead it is in the hands of advocates.
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11. I guess all of this stuff on CRF and the like is what some people might think is the sophisticated end of the denialism spectrum. But there is nothing sophisticated about it. No one has ever imagined that the climate didn't change in the past, nor that there are other inputs into global warming apart from greenhouse gases, nor that the climate hasn't exhibited fluctuations over the past 150 years, or even the last 30 years, as a result of some of those inputs. But to be rabbiting on, at such length, about these minor matters, while the great big CO2 elephant in the room keeps trumpeting for attention, is a sign of the same old denialism that is based on an unshakeable ideology that either (or both), humans can't affect a god-given home; or unfettered capitalism based on an ever increasing dependence on burning fossil fuels is the only way to conduct human affairs.
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12. This is just breaking – it appears that the underlying rate of warming between 1950 and 1997 was 0.1 degrees per decade. I would of (and have) used 1945 and 1998 – and get 0.08 degrees centigrade per decade. http://www.uwm.edu/~kswanson/publications/2008GL037022_all.pdf http://www.realclimate.org/index.php/archives/2009/07/warminginterrupted-much-ado-about-natural-variability/ Read carefully because Swanson supplies all necessary pre-digested rationalisations for global warmists. Although it is not new or startling science it is capitulation to the bleeding obvious. http://rogerpielkejr.blogspot.com/2009/07/two-decades-of-no-warming-consistent.html I am content to leave open the question of whether this is a longer term trend. The point is that 0.8 degrees per decade (and declining sensitivity to greenhouse gases) is not sufficient to warrant restricting the economic aspirations of billions of people. RealClimate states that this is not global cooling (at least not following the next decade or so) but natural variation - due to globally synchoised sea surface temperature changes triggering climte shifts over 20 to 30 years - on a warming trend. Has anyone argued that we can keep increasing carbon dioxide emissions. Certainly people like Bjorn Lomberg argue for an economically and technologically rational transition that doesn’t put millions of lives in the developing world at risk. And yes – stable democracy and a minimally regulated capitalism is the only way billions of people will emerge from poverty this century – although this would be more a policy than a science thread. So David, stop putting words in my mouth. If it is a contest between God and capitalism and aetheism and socialism - I am on the side of the angels.
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13. damn it - I meant 0.08 degrees per decade
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14. Robbo says "declining sensitivity to greenhouse gases" That implies that climate sensitivity is selective and variable, quite an interesting concept. References?
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15. One need to be carefull before coming to conclusions from linear trends. Indeed, the choice of the time interval is not neutral and can not be chosen arbitrarly. Also, the natural variability needs to be taken into account. Luckly there are statistical criteria to be met. As for the first issue (the time interval) you need to look at the residuals and no trend must be present. You can also look at autocorrelation and be sure it is minimal. This criterion excludes both '50-'97 and '45-'98 intervals. This does not mean you can't use them but you cannot draw robust conclusions, just a rough average trend. Using GISS data and trying to go as far back in time as possible, I found the interval 1970-2008 consistenly linear with a trend of 0.165 +/- 0.014 °C/decade. As for variability, you need to calculate the standard deviation of the residuals and use the standard 2*sigma criterion (equivalent to the 95% confidence level). Doing this will make apparent that nothing has changed up to now (2008), all the data points are within the +/- 2*sigma interval. Also, the last decade is nowhere near an anomalous deviation from the trend. Before claiming that we are in period of cooling or even flat temperatures we need to wait until the anomaly drops consistenly outside the statistical significance range. Using the same data and range as before I found a natural variability (2*sigma criterion) of about +/- 0.2 °C. It's worth to notice that even using smaller intervals down to the last decade sigma remains unchanged and again all the points are within +/-2*sigma, including those commonly considered extremes.
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16. Philippe, This is simply a fundamental concept of atmospheric physics. Greenhouse gases are transparent to shortwave radiation and opaque to specific bands of infrared radiation depending on the gas. As there are already gases in the atmosphere - some of the radiation is already blocked. More gas doesn't linearly decrease transparency of the atmosphere to IR - rather the transparency exponentially declines with each additional molecule. Once the IR window is closed - no amount of addtional greenhouse gas will trap more IR - but we are not there yet. In fact, I once calculated what would happen to global temps if the IR window was closed completely (it's an engineering thing) - and I don't think we want to go there. It is why there is a quasi linear response to an exponential increase in greenhouse gases. Yes - climate does respond to anthropogeninc greenhouse gases - I'm just not sure what it is. The upper limit appears to be the trend between 1946 to 1998 rather than 1976 to 1998. This makes a difference between - oh hell - we are all going to die and we have some time for human technological capacity to make a difference. Instead we have all these people - including the UN - who are wildly exaggerating the threat - and they admit to that all the time - and saying they can solve the problem with more taxes and bigger government. Excuse me for being hyper skeptical. Trust me - I'm a scientist/engineer. No don't do that - look it up on Wikepedia. Cheers Robbo
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17. Riccardo. You are torturing the data - up against the wall MF! Cheers Robbo
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18. re61 David Horton "But to be rabbiting on, at such length, about these minor matters, while the great big CO2 elephant in the room keeps trumpeting for attention, is a sign of the same old denialism that is based on an unshakeable ideology that either (or both), humans can't affect a god-given home; or unfettered capitalism based on an ever increasing dependence on burning fossil fuels is the only way to conduct human affairs" You left one important, strong human ideological tendancy out. Socialist-determinism, the worst historical distorter of data on record. (eg eugenics, communism, race-based Nazism). I think some communist propaganda posters depict capitalism as a big elephant, but I don't know what they would have made of human-induced global warming... It is amazing, that just like Karl Marx, you just cant see the weaknesses and common disortions in your own side of the argument. (eg 1. Karl Marx was so blind he scoffed at the idea that factory managers would be tempted to distort/exploit the new 'economic system', not to mention the 'radical intellectuals' themselves- just like you seem to have trouble doing...) (eg 2. check out Pipes of Harvard Uni's book on Communism-who claims that communism was largely founded by radical intellectuals-just like the human induced C02 warming agenda)
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20. "You left one important, strong human ideological tendancy out." Nothing says Strong Science quite like inferring that your adversaries are communists. Heckofa rebuttal. Well played.
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23. Chris, "1. While we've been discussing minutae of the solar/cloud/climate response the obvious thing that I think we agree on is that there has been no significant secular trend in the cosmic ray flux (CRF) since detailed measures began in 1958. So the very large global scale warming of the last 30-odd years has nothing to do with the CRF." I don't really disagree here, I suppose though I think that there might be a trend vis a vis the GCRs. IAC, I don't think cosmic ray flux has been a major contributor to the short term temperature trends. What I find puzzling, however, is the complete lack of interest in the *long-term* correlation of CRF and climate events. Since I consider this long-term correlation to be pretty definitive, this influences my interpretation of short-term measurements as well. If I ignored the long-term correlation as you do, I might well come to the same conclusions as you. http://arxiv.org/PS_cache/arxiv/pdf/0804/0804.1938v1.pdf IAC, I can see a lot of reasons why relatively small and fairly short-term varations may not be easily seen(leading to contradictory answers being found by say Erlykin and Harrison). I cannot, however, think of a good reason why multiple long term analyses demonstrate a correlation in different time schemes and proxies, where a relationship does not actually exist. I further think that the analysis of climate issues is massively complicated and it is fairly easy for mistakes to be made. Given this, it is pretty easy to imagine that what seems true after reading one paper may not turn out to be accurate in the future. I think you are somewhat unfair to Svensmark and Shaviv, but there is no reason to keep beating that horse. I don't think there is anything particularily illogical about their arguments. I still submit that you are much too quick to rule out the link between the solar cycle and cloudiness(based perhaps on the most recent cycle contradictory data). I feel that this link is pretty well accepted (by Erlykin et al. certainly). There must be some way that sunspot counts get reflected in the price of wheat and I don't see how a 0.1-0.2 deg. C could do it. Cheers, :)
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24. Robbo, i have really nothing to comment on the torturing of data. It's just very basic statistics without which you can make the data tell you whatever you like. As infact too often happens. Swanson et al. identify the periods differently from you. "The top panel in Figure 1 shows that in a statistically rigorous sense such synchronizations only occurred four times (1910-20; 1938-45; 1956-60; and 1976-1981) during the 20th century, and three of those synchronizations (all but 1956-1960) coincided with shifts in the climate state." Hence, the period starting in '38-'45 ended in '75-'81. I started in 1970 but could have started in '75 or '81 as well, it makes no difference. Autocorrelations is progressivly lower the more you average. It does not depends on the time range but on averages. In monthly data (often quoted to "demonstrate" the cooling of the last decades) it's larger, lower for annual and even lower for longer averages. And yes, the variability is due to ENSO, volcanos, etc.; pretty random, isn't it? You could even check the degree of randomness and, what a surprise, it behaves pretty much similar to autocorrelation. But ... wait ... it's statistics again ... :D Anyway, if you have time to check, ENSO (MEI index) and volcanoes explain the great part of the fluctuations (almost all indeed) superimposed on a monotonic increase. Finally, 1998 is indeed your cherry picking. Swanson et al just hypothised that there has been a climate shift in 2000-'01 not in 1998. And it is just an hypothesis because they could not find any cause and the time span is too short. From Swanson's post on RealClimate: "Whether or not such a halt has really occurred is of course controversial (it appears quite marked in the HadCRUT3 data, less so in GISTEMP); only time will tell if it’s real." And I agree. Like it or not the last decade is still largely inside the natural fluctuations.
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26. Chris assumes that lack of increase in neutron count from 1953 implies that this does not correlate with increasing temperature. He essentially denies a 1150 year correlation based on half a century of observation. Utterly ridiculous. The true interpretation is that cosmic ray flux peaked in the last half of the 20th century on a 1000 year high at least. How should this translate into global energy storage. Solar irradiance changes very little – yet climate changes over 1500 year cycles. This has led to the pursuit of a GCR/Cloud connection to explain the discrepancy. The theory suggests a millennial low in cloud cover last century - but reasonably constant over period of the neutron record. As we have already seen, Chris confuses energy flux with energy – particularly as it accumulates in the ocean. The increase in shortwave radiation results in a radiative imbalance that takes some time to work through the system. See this Stanford University site for a far more balanced and considered discussion than is provided by blinkered global warmists. http://www2.slac.stanford.edu/vvc/cosmicrays/cratmos.html Contrary to the unscientific certainty of global warmists – this is not 100% certain. However, there are other cyclic processes that are far more certain. The planet is not warming for 20 to 30 years from 1998.
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27. "The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible" If you really believe this, then I know I have nothing to learn from you. The other statement I was referring to earlier was this one: "declining sensitivity to greenhouse gases" i.e. variable sensitivity to a specific radiative forcing.
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28. #75 "Does Thumb's post apply to the insistance that denialists are Christian and capitalists? " #62 "If it is a contest between God and capitalism and aetheism and socialism - I am on the side of the angels."
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29. Philippe, 'The freezing point of carbon dioxide is -57 degrees centigrade. The lowest temperature ever recorded was -89.2 at Vostok in 1983. CO2 snow seems broadly feasible - although I am not sure that I would claim any climate implications - other than it is bloody cold in Antarctica.' You quote me out of context and imply a greater sigificance for a fun idea than it warrants. As I have explained - this is declining climate sensitivity to increasing greenhouse gases based on fundamental atmospheric physics. Bit of a shorthand - but I have tried to explain the concept. Are you saying this is wrong? There is no specific radiative forcing - just one forcing at one level of gases and another forcing at another - the relationship is not linear.
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30. David, I don't deny that I am both a theist and a capitalist. I think that people who think that evolution doesn't need God don't understand Einsteins's space-time continuum. In the context of that discussion - my comment was in relation to stable democracy, small government, minimally regulated capitalism and the reduction in global poverty. I can't help if you have a problem with that but this is not the place and I didn't raise the subject.
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31. Let’s have another quick look at clouds. There is a lot of useful data on Professor Ole Humlum’s homepage at: http://www.climate4you.com There are records of clouds from 1985. They show declining cloud cover to the turn of the century and increasing thereafter. Goode et al 2009 (can be found on the bibliography page of Project Earthshine – show this as albedo changes of a decrease in Earth albedo of 1% (additional shortwave of 3.5 W/m2) and an increase after 1999 of 0.75 % (less shortwave at the surface of 2 W/m2). High and low cloud in the climatically important equatorial zone declined to 1998 and increased thereafter. While the causes are not clear, it seems clear that 1998 marked a transition in biological, oceanographic and climate systems. Transitions occur in the instrumental and proxy records on a 50 year cycle – and it is interesting to consider a heliospheric /cloud connection. It may be that the cycle is a mode of internal dynamic variability that result in cloud changes.
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32. re #80: "I think that people who think that evolution doesn't need God don't understand Einsteins's space-time continuum." It's pretty clear that people who use the phrase "space-time continuum" in the same sentence as "evolution" don't understand either of those things. It's a bit like saying "i think that people who think that ducks don't need bicycles don't understand computers" - the sentence parses correctly, but really doesn't say anything useful...
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33. Gewtting back to the topic of ocean-earth heat lag. Hansen 2005 states: "Levitus et al. (14) compiled ocean temperature data that yielded increased ocean heat content of about 10 W yr m-2, averaged over the Earth’s surface, during 1955-1998". Yes, as expected by heat lag from the sun to the 1990s. But then he states: "First, the predicted energy imbalance due to increasing greenhouse gases has grown to 0.85 ± 0.15 W/m2". In other words he ENTIRELY assumes that past century T rise is by greenhouse gases first, which has therefore created a "predicted energy imbalance", by "increasing greenhouse gases". If we assume an energy imbalanace, then we get an energy imbalance. Mindbloggingly circular and stupid. There is no evidence to conclude, as he does, that the there is an energy imbalance at present, unless one assumes that T is rising by C02 in the first place, as he states above, that he does. This is not proof, is is circular reasoning. If we assume an energy imbalanace, then we get an energy imbalance. He uses the same argument further down to get a figure of 0.6 degrees C still 'in the pipeline' ie from ocean heat content, ie imbalanced with c02 forcing. NOWHERE does he discuss or address or acknowldedge the fundamental assumptions of the models he bases this figure on, ie that he ASSUMES T rise is being driven by c02, and not the sun. Ill repeat it for the sake of clarity: "the predicted energy imbalance due to increasing greenhouse gases has grown" How many circular assumptions kiddies are in this statment?? I count 3. 1. "predicted energy imbalance"..ie based on their being an energy imbalnace due to c02 driving T. 2."due to increasing greenhouse gases"-which assumes that they are driving T. No mention of the sun, or heat lag from such. 3.Has grown-ie if you assume the first 2 you get the last-has grown. Based on this sort of feedback reasoning, I predict that their T predictions, energy imbalances, and such, will just keep going up and up, because there is nothing stopping their "self-reinforcing reasoning feedback loops" from just getting larger and larger. Meanwhile, T hasnt risen in the last 10 years, because it is not subject to the 'global warmists by humans' self-reinforcing reasoning-positive feedback loops. Heat lags have now stabilised, there is no energy imbalance, and T will not rise over the next 10-20 years, unless the sun becomes more active again.
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34. I also strongly suspect, that Figures 1 and 2 above are based on model assumptions relating entirely to c02 driving T as well (see my previous post). They are therefore not evidence, jsut self-perpetuating data models, adjusted at whim as a modeller sees fit. Figure 1's 'runs' above are based on Hansens model assumptions of T being driven by c02 in his paper; figure 2 'erbs' and 'ceres' and also based on predicted fluxes-assuming an imbalance with respect to T being driven by c02. They are both therefore circular-reasoning graphs which dont show anything except the whims and assumptions of the modellers who compiled them. i have seen similar modelling assumptions in modelling work by financial instutions.
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35. re 82 Nothing to do with heat lag but the connection is with the arror of time. The past lost - the future unformed - all there is the evolving moment which moves forward in time like an arrow. Space-time does not evolve - it simply exists. ‘It is believed to be a 'continuum' because so far as we know, there are no missing points in space or instants in time, and both can be subdivided without any apparent limit in size or duration. So, physicists now routinely consider our world to be embedded in this 4-dimensional Space-Time continuum, and all events, places, moments in history and in the future, actions and so on are described in terms of their location in Space-Time.’ http://einstein.stanford.edu/content/relativity/q411.html Can evolution be said to occur if the future form exists in a future moment in the time-space continuum? Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe.
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36. re 82 Nothing to do with heat lag but the connection is with the arror of time. The past lost - the future unformed - all there is the evolving moment which moves forward in time like an arrow. Space-time does not evolve - it simply exists. ‘It is believed to be a 'continuum' because so far as we know, there are no missing points in space or instants in time, and both can be subdivided without any apparent limit in size or duration. So, physicists now routinely consider our world to be embedded in this 4-dimensional Space-Time continuum, and all events, places, moments in history and in the future, actions and so on are described in terms of their location in Space-Time.’ http://einstein.stanford.edu/content/relativity/q411.html Can evolution be said to occur if the future form exists in a future moment in the time-space continuum? Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe.
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37. Based on this sort of feedback reasoning, I predict that their T predictions, energy imbalances, and such, will just keep going up and up, because there is nothing stopping their "self-reinforcing reasoning feedback loops" from just getting larger and larger. Meanwhile - the duck rides the bicycle around and around at relativistic speeds until it disapears up it's own ring in a secular humanist universe Actually, the duck experiment seems to work well. Thanks Thingadonta.
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39. re: #86 "Can evolution be said to occur if the future form exists in a future moment in the time-space continuum?" This is gibberish. Do you really expect to be taken seriously by anybody when you write such bizarre nonsense as this? At least now your complete inability to follow the science makes some sense. Chris, your herculean efforts to bring facts and reason to the discussion (nice summary above BTW) are clearly wasted on somebody who writes such nonsense. This is no longer a scientific discussion, it is an exploration into abnormal psychology. Interesting, but other than learning about the psychological barriers to understanding that deniers have, it has little connection to science. Perhaps Robbo should go "debate" the timecube guy?
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40. Honestly - I link and quote a Stanford University website on what is a widely accepted understanding of space-time and a foolish little person insists on compounding their idiocy. Time would be better spent in expanding both their education and their imagination. Chris at least raises scientific issues – if in his usual disingenuous way. The 1150 year is of course the Usoskin correlation as he knows full well. I get it – you don’t think there is a link between clouds and cosmic rays and that natural climate variation is caused primarily by changes in solar irradiance. The usual consensus is that changes in irradiance are insufficient to explain observed climate variation. See for instance: Shortwave forcing of the Earth's climate: modern and historical variations in the Sun's irradiance and the Earth's reflectance, P.R. Goode, E. Palle, J. Atm. and Sol.-Terr. Phys., 69,1556, 2007. PDF I advise that there is an error on Figure 4 in that the left hand axis was mislabelled – which was brought to my attention by Chris misinterpreting this as a 20 fold reinterpretation of the data. I am very bored with the endless repetition of this argument and your dogmatic assertions – particularly so as I am barely involved in this line of argument. I merely referred to the Stanford University high energy physics site which suggests that the idea should not be dismissed out of hand – very much more in the spirit of scientific openness and debate. Much as is the work coming out of CERN and elsewhere. But you know best. I am much more interested in the empirical science of clouds, ocean temperature, rainfall and biology and in the climate transitions of the mid 1940’s, the mid 1970’s and following 1998. My exact words were that while ‘the causes are not clear, it seems clear that 1998 marked a transition in biological, oceanographic and climate systems. Transitions occur in the instrumental and proxy records on a 50 year cycle – and it is interesting to consider a heliospheric /cloud connection. It may be (however) that the cycle is a mode of internal dynamic variability that result in cloud changes. If you have 1 reference that questions this – I would be happy to hear of it.
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41. I have been edited - LOL 'The 2008 defensive reaction to the recent lack of global warming can be considered as another fine example of groupthink. A premature sense of apparent unanimity prevails (most scientists agree that global warming is real and manmade), and any doubts and contrary views are suppressed (by ... institutions launching lists of ‘correct’ answers to a number of critical questions (so-called myths), including the lack of warming since 1998).' 'To make groupthink testable, Irving Janis devised eight symptoms indicative of groupthink (1977). 1. Illusions of invulnerability creating excessive optimism and encouraging risk taking. 2. Rationalising warnings that might challenge the group's assumptions. 3. Unquestioned belief in the morality of the group, causing members to ignore the consequences of their actions. 4. Stereotyping those who are opposed to the group as weak, evil, biased, spiteful, disfigured, impotent, or stupid. 5. Direct pressure to conform placed on any member who questions the group, couched in terms of "disloyalty". 6. Self censorship of ideas that deviate from the apparent group consensus. 7. Illusions of unanimity among group members, silence is viewed as agreement. 8. Mindguards — self-appointed members who shield the group from dissenting information. Groupthink, resulting from the symptoms listed above, results in defective decision making. That is, consensus-driven decisions are the result of the following practices of groupthinking: 1. Incomplete survey of alternatives 2. Incomplete survey of objectives 3. Failure to examine risks of preferred choice 4. Failure to reevaluate previously rejected alternatives 5. Poor information search 6. Selection bias in collecting information 7. Failure to work out contingency plans.
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42. Context is irrelevant in the case of the CO2 snow idiocy. No other context is necessary than the atmosphere of this planet. In this context, "broadly feasible" is so far off the mark that it's downright comical. No implication about climate needs to be considered at all. The idea is not fun, it's stupid, and anyone entertaining it as even remotely possible should be met with profound distrust on science considerations.
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43. "Honestly - I link and quote a Stanford University website on what is a widely accepted understanding of space-time and a foolish little person insists on compounding their idiocy. Time would be better spent in expanding both their education and their imagination." Methinks someone's feelings were hurt. "'To make groupthink testable, Irving Janis devised eight symptoms indicative of groupthink (1977)." Now you're projecting. You gave your game away with this line: "...is not sufficient to warrant restricting the economic aspirations of billions of people." Your entire ongoing argument is based on finding anything, however small, that supports what I would argue is a false premise; that addressing our continued contribution to greenhouse gases would somehow have an adverse economic affect on "billions of people." In the real world in which I work converting to high efficiency and alternative energy sources creates jobs and holds an easily calculable payback when measured against current systems and fossil fuels, which, BTW, simply can't go on forever. Reducing greenhouse gases might be a driving force for some, but the real selling point for moving the global economy into green energy technologies is their potential to expand and enhance the economic aspirations of billions of people.
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44. "Similar arguments apply even more strongly in the past. Changes in 10Be in ice cores and 14C in tree rings is a measure of varying solar outputs represented by the CRF. But just as with the very detailed contemporary analyses (see my post #71), there is no good a priori reason for assuming that any climate-related consequences of solar variation are causally related to the putative CRF component of the solar variation. In fact recent evidence suggests that this a priori assumption is a very weakly supported one." The problem with this line of argument is that total irradiance doesn't vary nearly as much as the climate has. Kirkby's 2007 review states that "...more recent estimates suggest that long-term irradiance changes are probably negligible". As such, since the total irradiance doesn't change much and the CRF does, the fact that CRF varies in tandem with climate changes, is good evidence that the CRF itself influences climate somehow. It is possible that some other solar-related property varies much more closely than CRF to the observed climate changes, but clearly irradiance changes themselves don't explain what we see happening. Cheers, :)
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45. I've been trying to understand RC's post on a simple model in the light of this article and, if possible, I would like to understand the reason for a difference. According to RC's post: σTs4 = S /(1 - 0,5λ) Where S = (1-a)TSI/4 λ = emissivity (0,769) However, as I understand it, according to this article, that would rather be: σT4 = S/λ Using RC's notation: λ = ε (emissivity) S = what in this article is S(1-A)/4 Are my numbers wrong? Are the two approaches based on different simplifications? Thanks! RC's post Formulas better displayed here
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46. The problem with this line of argument is that total irradiance doesn't vary nearly as much as the climate has. Kirkby's 2007 review states that "...more recent estimates suggest that long-term irradiance changes are probably negligible". As such, since the total irradiance doesn't change much and the CRF does, the fact that CRF varies in tandem with climate changes, is good evidence that the CRF itself influences climate somehow.
That doesn't seem logical to me Shawnet. It begs rather a lot of questions. 1. The climate transitions since the Maunder minimum are understandable in terms of known contributions from solar, volcanic and greenhouse contributions (points 4,5 and 6 of my post #88). That doesn't mean that my breakdown of contributions is exactly correct! However one doesn't need to postulate any as yet uncharacterised forcings (solar or otherwise) to understand this variation. 2. That may or may not apply to the previous few centuries, e.g. involving the MWP. The climate variation during this period isn't so well characterised, and some of the climate variation may be regional and due to changes in ocean/atmospheric heat transport (my point 3 in post #88). Of course that begs the question of whether these heat transport variations are internal modulations of the climate system or are externally forced. 3. Previous to that there isn't a very good understanding of global Holocene climate variability I believe (I haven't seen serious Holocene global paleoproxy reconstructions other than these: Holocene_Temperature_Variations.png There are various bits of highly localized proxies (stalagmites; glacial ice etc.) which correlate solar proxies with climate proxies, but whether these are representative of global scale changes isn't very clear I think. So I'm not sure we can say that the total irradiance hasn't varied as much as the climate has, since we haven't got much evidence for the climate variability and solar irradiance variability during periods of the Holocene before a couple of millenia ago. Note that some of the early Holocene climate variability (around 8000-6000 years ago, I think) is a Milankovitch effect). 4. The fact that the CRF might vary more than solar irradiance (I assume you mean in terms of % variation around some mean), doesn't necessarily say anything about the relative contributions of the CRF changes and irradiance changes. After all, if CRF changes don't have a significant climate effect it doesn't matter how much these change. 5. Obviously climate has changed considerably in the past. But this is largely understandable in terms of earth orbital variations (Milankovitch cycles) with greenhouse gas and albedo feedbacks (last couple of million years), and further into the deep past through changes in greenhouse gas concentrations (rising CO2 concentrations from tectonic processes; reducing greenhouse gas concentrations from weathering processes), the progressively decreasing solar constant as we go back in time (Kirkby must surely know this, 'though perhaps by "long-term" he doesn't mean millions of years time scale), and tectonic activity. 6. So I'm not sure that we need to postulate any solar contributions outside irradiance changes. That's not to say that these don't exist (the evidence for the direct CRF-climate contribution is weak in my understanding of the science - e.g. see my post #71); it's just that they haven't been identified (to my knowledge), and aren't necessarily required to explain anything.... ...what do you think? Is there some serious evidence that some non-irradiance solar contributions are rwquired to explain particular climate transitions/variations?
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