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Rob Painting at 17:12 PM on 17 March 2013Water vapor is the most powerful greenhouse gas
Absolutely Doug. But it gives insight into how some contrarians operate.
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Tom Curtis at 14:20 PM on 17 March 2013Lessons from Past Climate Predictions: Syun-Ichi Akasofu
Before responding to Matthew L @35, I checked a few details, which themselves raise additional issues. The least important of these is that the graph of the running five year average of the Wood for Trees (WfT) temperature index is offset by about - 4 months. Because of the steep slopes in the area, that offsets the start point of the prediction by about 0.005 C. Having noted that, that seems inconsequential to me. I note it, howeve, in case anyone else finds the same discrepancy.
Also of little consequence, Matthew L's extension of the WfT observed index is too low. On WfT, the low point around 2010 is no lower than that around 2007. Matthew, however, places it around 0.005 C lower.
The most important issue, however, is that Akasofu's prediction is incorrectly stated by Akasofu. In all his figures, Akasofu shows a sine like wave in representing his 60 year cycle. That is consistent with the various indices (AMO, PDO) that he presents as evidence of that oscilation. Therefore, his prediction is of a sine like oscilation superimposed on a linear 0.5 C per century trend.
In a sine like oscilation, however, as the wave approaches the peak or trough, the slope of the sine like component of the wave approaches zero. That means, at the peaks and troughs, the underlying 0.5 C per century trend should be evident. Given that Akasofu states that the most recent peak was in 2000, and the most recent trough in 1970, he should predict a 0.05 C per decade trend for the ten years (or indeed, any symetrical interval) bracketing those years. So, his predicted trend from 1995-2005 is 0.05 C per decade. It is actually 0.213 C per decade (GISTEMP; NOAA: 0.212; HadCRUT3: 0.234; HadCRUT4: 0.222). 1970 fairs a little better, with trends ranging from 0.087 to -0.016 C per decade (GISTEMP and HadCRUT4).
Of course, with a sine wave fluctuation, the maximum negative trend is predicted to be reached in 2015, so the trend from 2000-current is predicted to be significantly negative (0.075 C/decade). In fact, it is positive (GISTEMP: 0.072 C/decade; NOAA: 0.044 C/decade; HadCRUT3: 0.008 C/decade; HadCRUT4: 0.043 C/decade).
However, Akasofu can only avoid refutation of his hypothesis by the recent data by acknowledging that over the short term, the impact of ENSO and volcanism dominate over long term trends.
That does not save him, however, for his prediction, with a sine like oscilation, shoud be for a maximum positive trend at around 1985, with the trend gradually developing to that point, before gradually falling back to 0.05 C per decade 15 years later. In fact, the trend from 1970 to 2000 is indistinguishable from a linear trend plus noise (as shown by the plateau in the trend, see graph below). The same can also be said of the trends from 1940 to 1970, and from 1910 to 1940. Indeed, the model of a sine wave superimposed on a linear trend performs very poorly in predicting trends:
(Successive 217 month trends for GISSTEMP and linear plus sine wave models. Click on graph for larger image.)
It should be noted that Matthew L's apparently sine like rate of change graphs are purely a function of using trend lengths approximately equal to, or greater than a half cycle. Doing so guaranttees a sine like graph for any underlying regular wave function (although the amplitude of the wave function approaches zero as the trend length gets large relative to the full underlying wave length.)
As previously noted, Akasofu can accomadate this discrepancy by allowing for large short term fluctuations related to ENSO. If he does so, however, he must explain why he makes no attempt to remove the ENSO signal, and why the underlying trend with the ENSO signal removed is so strongly positive.
Finally, it could be reasonably argued that I am being too kind to Akasofu. In modeling his prediction, I have used a regular sine wave with an amplitude of 0.2 C and a wave lenght of 60 years. In fact, in his only direct presentation of the wave I am aware of, he shows two full cycles, with no cycle having the same duration, amplitude or shape of any other:
(From Akasofu, "On the recovery from the LIA", Natural Science, 2010, Fig 4d)
Allowing this, essentially freehand modification means Akasofu could have fit any sine like pattern in the tempeature data, regardless of its cause. It also means the pattern he fitted is not predictive, for no information is contained about the lengths or amplitudes of future "cycles", given that these parameters are allowed to vary freely.
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Matt Fitzpatrick at 13:59 PM on 17 March 2013February 2013 Arctic Sea Ice Death Spiral Update
In fairness, the perspective in the second figure exaggerates values below 30 thousand km3 in more recent years.
But the circle (spiral) graph is stunning. It even provides a tidy disappearing point for when months start hitting zero. If not for that, I imagine some people might take the flat segment on a non-circular graph between September 20X0's zero and September 20X1's zero as "evidence" of no warming.
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Leto at 13:55 PM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Hi Roger,
When I asked for details, I was wondering whether Ridley had mounted any sort of sophisticated botanical argument of relevance to the science of climatology. If you can't answer without mentioning fears of a mini-ice age and mass starvation on the back of "lacl of warming for over a decade", or without dismissing concerns about AGW as "inane", it does give me some idea of the audience he is pitching to, at least.
Comment policy on this site prevents me from saying much more of what I think, so I'll leave it at that. Some of the more patient folk here at SkS might be ready to discuss your ideas with you.
I'm not sure you've done Ridley any favours here.
Leto.
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Bob Lacatena at 13:44 PM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
52,
Tom, the paper does have a different focus from Chapter 4 of the thesis, because Chapter 4 of the thesis was preliminary material in support of 3 distinct and separate goals of the thesis, but with no other intent of its own, while the paper which grew from and builds upon Chapter 4 has a purpose in and of itself. The distinction is critical to the discussion. The distinction is, in fact, the crux of the argument.
When Chapter 4 consisted of a reconstruction in support of questions concerning paleo issues several thousands of years ago, the only relevant aspect of modern temperatures within Chapter 4 was some overlap with more recent proxies so as to calibrate and validate the temperature record extending further back.
When Chapter 4 grew into a paper intended explicitly to comment on the variability of climate for the past ten thousand years, as compared with recent climate change, then the issue of more recent temperature change became relevant and was included.
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Doug Hutcheson at 13:30 PM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Roger Dewhurst @ 33, your claims seem to be extraordinary and require extraordinary proofs. For a quick review, I recommend having a look at the following articles here:
- http://www.skepticalscience.com/co2-plant-food.htm
- http://www.skepticalscience.com/heading-into-new-little-ice-age.htm
- http://www.skepticalscience.com/global-warming-stopped-in-1998.htm
Moderator Response: [DB] Thank you. You pre-empted the need for further Moderator intervention. Interested parties may engage Roger Dewhurst on the appropriate thread. -
Doug Hutcheson at 13:17 PM on 17 March 2013Water vapor is the most powerful greenhouse gas
Rob Painting @ 166, the extraordinary claim that the net response to a doubling of CO2 would be a temperature increase of 0.2OC requires more than "a tiny kernel of truth", I would have thought. I have emailed Radio National to see if they have a transcript of the interview and will post here again, if I get a response.
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Tom Curtis at 13:05 PM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
barry @51, the paper does not have a different focus from Chapter 4 of the thesis; and nor does it, except for minor modifications, have different methods. Further, pointing out that it has different methods (minor as the changes are) does not answer the question as to which difference in the methods resulted in the changes in the data presented in otherwise equivalent graphs. Nor is it clear from the description of the methods in the paper and thesis in what the difference lies.
While I agree completely with your final sentence, the issued raised in bad faith by McIntyre and Watts could also be raised in good faith. Merely pointing out that McIntyre and Watts do not ask the questions in good faith does not show the questions do not need an answer.
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barry1487 at 11:53 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
"And yet, as might be expected, Dr. Marcott chose to build upon his previous work and to take it in a new direction, one relevant to a major issue of the day, anthropogenic climate change."
Anthony Watts did the same for the US temperature record, building upon the work of Fall et al (he was a co-author) when drawing up his unpublished effort on station exposure. Both papers give a pie chart on percentage of stations with different classification. They are different from each other.Should we now imply that A Watts has done something questionnable by 'altering' the latter graph?
No - the papers have a different focus (and methods). Same with Marcott. Honest participants would take the trouble to find out why there are differences, and not just make implication with 'questions' they are not interested in answering for themselves.
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Roger Dewhurst at 11:50 AM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Ferns, cycads, horsetails and the like evolved in palaeozoic times with far higher levels of carbon dioxide in the atmosphere. Most of the evolution of the angiosperms, at least to generic and family level, had taken place before the end of Jurassic times, also in an atmosphere much richer in carbon dioxide. The level of carbon dioxide in the atmosphere today is sub-optimal for most plants. This is of course a fact well known to the operators of commercial greenhouses. It is no surprise really, and to be expected, that the increase in atmospheric carbon dioxide in recent decades has stimulated plant growth.
Should the inane pleas for reduction in atmospheric carbon dioxide actually succeed plant growth will slow and starvation will become the norm in much of the third world. Should we be entering a mini ice age, which is a distinct possibility given the lacl of warming for over a decade and the low level of sunspot activity, we might just need all the carbon dioxide we can get into the atmosphere!Moderator Response: [DB] Any further discussion of this line needs to be taken to the CO2 is plant food thread. Off-topic sloganeering struck out. Interested parties may engage Roger Dewhurst on the appropriate threads noted by Doug Hutcheson. -
Roger Dewhurst at 11:37 AM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Leto.
Ridley's initial claim is that the earth is getting greener and he presented good evidence for that. Do you wish to dispute that point?
He also claimed that the increase in atmospheric carbon dioxide contributed to that greening arguing, on correct botanical grounds, that carbon dioxide is plant food.
Do you wish to dispute that point? Are there any point in his talk that you would like to dispute? If so what are they?
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barry1487 at 11:20 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
DSL,
Alas, Poole could've used a more robust representation of "climate change" instead of just equating it with temperature as Luntz does. Climate change somewhat obviously can be changes in temp, general circulation, precipitation, weather patterns, wind, cloud cover, frequency of "extreme" events, etc.
While illuminating the definition of climate change in this way may be laudable, Poole's thesis was on the politicisation of language, and he articulated the intent of the political actors at the time. It would be great if the faux skeptics just dropped the talking point, but seeing as they bring it up as a political argument (cf Anthony Watts) it's worthwhile knowing how discussion of the terminologies actually played out. Watts claims that AGW 'proponents' fiddled with the language. But it wasn't the scientists or the media or Greenpeace that focussed on the political ramifications of the two phrases, it was those with vested interests in downplaying AGW. It still is.
Watts is not only wrong, his criticism is completely misdirected.
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Rob Painting at 11:15 AM on 17 March 2013Water vapor is the most powerful greenhouse gas
Doug - it's a bogus claim, but there is a tiny kernel of truth in there. Increasing the water vapour content of the atmosphere would indeed block more sunlight from reaching the Earth's surface. It isn't sufficient to counteract the warming impact from increased water vapour though.
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Treesong2 at 10:32 AM on 17 March 20132013 SkS Weekly News Roundup #11
The link for 'Why saving the planet means saving the economy, too' is the same as the one for 'Five companies vie to build wind farms off North Carolina coastline'.
Moderator Response: [JH]Link fixed. Thank you for bringing this to our attention. -
Doug Hutcheson at 10:14 AM on 17 March 2013Water vapor is the most powerful greenhouse gas
I was listening to Radio National (Australia) yesterday and heard Pielke Jr claim that water vapour actually has a negative forcing, meaning a doubling in CO2 would cause a global temperature change of 0.2oC. I was astounded, not surprisingly! Hands up all those scientists who think CO2 has a negative forcing? Anyone? (Cue sound of crickets ...)
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DSL at 09:15 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
TC, Sph: in what world are you not both right? Questioning the difference between the graphs is a legitimate enterprise if done to further one's understanding of the research. I questioned the difference myself until I saw the reasons (confirmed more completely by TC). It's clear from Watts' and McIntyre's rhetoric that they have no interest in furthering their understanding or disseminating that understanding to the people they've already confused.
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Leto at 08:47 AM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Hi Roger @30,
Care to put some detail into that claim? Given all of the nonsense Ridley has spouted in the past, I would be surprised if he got something right, but it's always interesting to hear the argument.
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jyushchyshyn at 08:44 AM on 17 March 2013State Department Downplays the Climate Impact of Keystone XL
If the Northern Gateway pipeline is also rejected, then rejecting Keystone will slow down oilsands development. But rejecting Keystone will not have any effect on what really matters in the fight against global warming; how much energy is provided by the combustion of hydrocarbons. If Keystone is rejected and if we continue to use hydrocarbons as we have to now, then we would just get the oil from OPEC. On the other hand, if someone actually had a plan to make the oil delivered by Keystone unnecessary, then whether or not the pipeline is built would be moot. If Keystone were built but not used, would that be such a bad thing, except for its investors.
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dalyplanet at 08:44 AM on 17 March 2013February 2013 Arctic Sea Ice Death Spiral Update
Nice graphics and the loss of volume is an eye popping if not heart stopping bit of information
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Roger Dewhurst at 08:38 AM on 17 March 2013Matt Ridley Risk Management Failure Deja Vu
Attacks on the messenger but the message escapes unscathed. Rightly so becuse he stuck to facts. Although Ridley is not a botanist his botanical arument was totally correct.
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Bob Lacatena at 08:29 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
...given the similarity of these descriptions...
So what? I've said repeatedly that the Nature paper was clearly based on Chapter 4 from the thesis, and it makes sense to have done so. Of course there were similarities. The question Watts posed was why was that particular change (adding the recent temperature record) made to the paper when it was not the original thesis, and the answer is clearly that it was not necessary given the objective of the original project.
That's all that matters here. Watt's inane query was "I wonder why the difference" and the answer is "because it was irrelevant to the purpose of the original thesis."
That's all.
Therefore it is intirely reasonable to ask about differences between them.
No, it's not. The reasons for the differences are obvious, and the reasons for pursuing it further are obvious as well – to stir up false controversy and to cast doubt upon the motivations and methods of Marcott. That's all this is, is a Watts/McIntyre denial hatchet-job, and it has no foundation whatsoever.
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LarryM at 07:48 AM on 17 March 2013February 2013 Arctic Sea Ice Death Spiral Update
The first Death Spiral graphic is visually striking and clearly shows the loss of sea ice in all seasons. Another permutation that might complement it and more clearly show the differences between seasons is for the radial scale to show, rather than absolute volume in km3, the percentage of the volume in 1979 that remains. I think it would show that the summer/fall ice is disappearing exceptionally fast.
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Tom Curtis at 07:12 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Sphaerica @46, from the Science article:
"We then assessed the sensitivity of the temperature reconstruction to several averaging schemes, including an arithmetic mean of the data sets, a 30° × 30° area-weighted mean, a 10° latitudinal weighted mean, and a calculation of 1000 jackknifed stacks that randomly exclude 50% of the records in each realization (Fig. 1, C and D, and fig. S4). Although some differences exist at the centennial scale among the various methods (Fig. 1, C and D), they are small (<0.2°C) for most of the reconstructions, well within the uncertainties of our Standard5x5 reconstruction, and do not affect the long-term trend in the reconstruction."
From the thesis:
"To test the reproducibility of our two methods for reconstructing the temperature stack, we experimented with various ways of calculating the globally stacked temperature anomalies (Figure 4.3 a,e). We divided the records into 10° latitudinal bins and weighted them by their cosine of latitude to test the sensitivity of our datasets being skewed toward the northern hemisphere. A jack-knife technique, where for each of the Monte Carlo simulations 50% of the records were randomly excluded, was also implemented to determine the sensitivity of the global stack to any one record or group of records. While some differences exist at the centennial scale amongst the various methods (Figure 4.3 a), they are very small (<0.2°C) for most of the reconstruction, well within the uncertainties of our stacked temperature record, and do not affect the long-term trend in the reconstruction, demonstrating the robustness of our record at the multi-centennial and multi-millennial scale."
And regarding the specific figure under discussion, from Science:
"(CandD) Global temperature anomalies stacked using several methods (Standard and Standard5x5Grid; 30x30Grid; 10-lat: Arithmeticmeancalculation, area-weighted with a 5° × 5° grid, area-weighted ith a 30° × 30° grid, and area-weighted using 10° latitude bins, respectively; RegEM and RegEM5x5Grid: regularized expectation maximization algorithminfilled arithmetic mean and5°×5°area-weighted). The gray shading [50% Jackknife ( Jack50)] represents the 1s envelope when randomly leaving 50% of the records out during each Monte Carlo mean calculation. Uncertainties shown are 1s for each of the methods."
And from the thesis:
"Comparison of different methods and reconstructions of global and hemispheric temperature anomalies.
a, Mean values of our global and hemispheric temperature anomalies using several methods (Standard – Arithmetic mean calculation; StandardNH – Arithmetic mean calculation of Northern Hemisphere records only; CosLat – Arithmetic mean calculation, cosine of latitude weighted; RegEM – Mean calculation using RegEM). The gray shading (Jack50) represents the 1! band when randomly leaving 50% of the records out during each Monte Carlo mean calculation."
There is no doubt, given the similarity of these descriptions that Fig 1 c from Science, and Fig 4.3 a from the thesis serve the same purpose within their respective documents. Therefore it is intirely reasonable to ask about differences between them.
What is not reasonable is to make insinuations of fraud when an entirely adequate potential reason is shown in the same group of graphs.
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Bob Lacatena at 05:44 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Tom,
The purpose of the project as a whole is explicitly and clearly stated in the opening chapter:
This dissertation addresses three issues related to paleoclimate in an attempt to shed new light on the mechanism and timing of climate and glacier changes in the past.
While the individual chapters may have strayed into other potential conclusions and uses, and while it may have evolved by this point in time to have a different application and to be published as a paper in its own right in Nature, there is no doubt that this was not the original intent, so to complain explicitly about the lack of careful comparison to current temperatures is an erroneous and baseless complaint.
And I did not dispute that elements of the paper did evolve into Marcott et al. Quite to the contrary, I explicitly stated:
And yet, as might be expected, Dr. Marcott chose to build upon his previous work and to take it in a new direction, one relevant to a major issue of the day, anthropogenic climate change.
All of my points still stand, specifically:
- The purpose of the original project, regardless of tangents, was not to evaluate past climate as a benchmark for current climate change, so no complaint can be made about the completeness of the thesis for that purpose.
- It is not only not unexpected, but rather to be expected that Marcott would use this as a foundation for further work, including application directly to current climate change. it would be surprising if he had not done so.
The Watts/McIntyre complaint is a complete and total misdirection, and anyone who falls for it should be ashamed of themselves (for failing to be more skeptical and sensible). Anyone who fell for it should do some introspection about what their own motives and desires might be (i.e. to ascertain the truth, or to arrive at a seeming truth which supports their hoped for outcome).
- The purpose of the original project, regardless of tangents, was not to evaluate past climate as a benchmark for current climate change, so no complaint can be made about the completeness of the thesis for that purpose.
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DSL at 04:33 AM on 17 March 2013Southern sea ice is increasing
newtja, Corr & Vaughan (2008) does not attempt to assess or quantify the effect of volcanic venting on the Pine Island glacier. The eruption discussed occurred roughly 2k years ago. It's possible that venting is helping the break up of PI glacier, but as you can see from the article above, and from Shepherd et al. (2013), there are greater factors involved. You might also check out Vaughan & Corr (2012). Here are the last lines of their abstract:
"We conclude that ice-shelf basal melting plays a role in determining patterns of surface and basal crevassing. Increased delivery of warm ocean water into the sub-ice shelf cavity may therefore cause not only thinning but also structural weakening of the ice shelf, perhaps, as a prelude to eventual collapse."
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rugbyguy59 at 04:27 AM on 17 March 20132013 SkS Weekly News Roundup #11
As a Canadian, when I first saw the headline Canada Losing its Seasons I thought "Oh no, another 'kids won't see snow' comment." However the article notes a variety of changes that are already started and changes that are much less weather dependent than "no snow" allusions. Still I'd be naive to think deniers won't (incorrectly) use it.
It all makes me wonder if I shouldn't send the kids north to get established as those who are their first usually benefit the most. Of course that would be based on an orderly migration north. With who knows how many millions making the trek I get the feeling the migration may not be particularly orderly.
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newtja at 03:57 AM on 17 March 2013Southern sea ice is increasing
How do the explanations in this article correspond to the 2008 paper by Corr and Vaughn in Nature Geoscience about volcanism affecting the Pine Island Glacier?
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John Mason at 02:17 AM on 17 March 2013Death in Jurassic Park: global warming and ocean anoxia
PS - this paper may be of interest to you: it does concern deeper water facies from the Toarcian:
An open marine record of the Toarcian oceanic anoxic event
Abstract.
6‰) negative excursion in d13Corg that, based on radiolarian biostratigraphy, is a correlative of the lower Toarcian negative CIE known from Pangaean epi-and pericontinental strata. A smaller negative excursion in d13Corg (ca. 2‰) is recognized lower in the studied succession. This excursion may, within the current biostratigraphic resolution, represent the excursion recorded in European epi-continental successions close to the Pliensbachian/Toarcian boundary. These results from the open ocean realm suggest, in conjunction with other previously published datasets, that these Early Jurassic carbon cycle perturbations affected the active global reservoirs of the exchangeable carbon cycle(deep marine, shallow marine, atmospheric).Moderator Response: [RH] Shortened link. -
John Mason at 02:09 AM on 17 March 2013Death in Jurassic Park: global warming and ocean anoxia
@ mlyle - sure: however the authors do state the following:
Evidence of an extinction event has
been reported in western Europe (e.g., [24,33–35]), South
America [36–37], Siberia [38] and northern Africa [39]. Although
definitive cause-effect relationships are not yet established, the
extinction has either been linked to the development of widespread
anoxia [27,37,40–41], or to global warming [32,42].Thus it seems a reasonable point to report upon. I agree that most Toarcian oceanic crust has been recycled, but the widespread occurrence of these black shales suggests something was afoot. Bearing in mind that shelf areas are particularly productive in terms of biodiversity, anoxia in these areas would have a particularly devastating impact.
N and P would be relatively easy to get into the system if widespread terrestrial erosion of soils was going on at the time.
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DSL at 00:48 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
And has McIntyre or Watts actually asked Marcott about the differences (instead of quite publicly insinuating that Marcott is guilty of some sort of fraud)? Have you addressed this issue with the presumably more "skeptical" Watts and McIntyre, Ray?
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mlyle at 00:29 AM on 17 March 2013Death in Jurassic Park: global warming and ocean anoxia
You have to be careful to make estimates of global ocean conditions from one locale, especially from the shelf-slope region. I can find basins today that are anoxic, but that doesn't mean the whole ocean is today. The paper puts forward an interesting hypothesis, but needs to show why one might expect this to represent global conditions. Unfortunately, there are few pieces of deep ocean floor preserved to actually test for global anoxia. Also, to get hyperproductivity, the problem is to get N and P into the oceans, not C.
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Tom Curtis at 00:27 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Ray @36, the graph you mention is not the only one to have altered between thesis and paper in Science. Specifically Fig 1 G (Science; Fig 4.3 C in the thesis) also differs. That figure shows the number of proxies available at different time periods. Most importantly, in the thesis it shows less than 10 proxies extend into the twentieth century. In contrast, in the Science article, shows 20 proxies available at the same time interval. As the same proxies appear to be used in each, this suggests that either Marcott has recieved additional, more recent data for several of the proxies, or that the interpolation using RegEm (as discussed both in paper and thesis) has been more extensively applied.
Regardless of the course, less than ten proxies is a very limited sample for determining global surface temperature and such a small sample is likely to have considerable biases. Therefore, more than doubling the number of available proxies is likely to result in changes in the reconstruction where the proxies are sparce (twentieth century), although adding the same number of proxies will have little effect where the proxies are more extensive (ie, prior to AD 1500).
Failing further evidence to the contrary, this would appear to completely answer the issues raised. You may want to ask yourself why this change in the number of available proxies has not been commented on at WUWT.
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Tom Curtis at 00:13 AM on 17 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Sphaerica @37, Chapter 4 of the thesis is specifically about the reconstruction of Holocene temperatures, and is analogous the Science paper, and has the same authors as the Science paper. It is also noted that that chapter would be submitted to Nature for publication. It is a reasonable supposition the Science paper is Chapter 4 as modified in the process of publication. That Marcott adresses other issues in other chapters of his thesis is not germaine, and does not rebut the general equivalence of Chapter 4 and the Science paper.
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DSL at 23:51 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Alas, Poole could've used a more robust representation of "climate change" instead of just equating it with temperature as Luntz does. Climate change somewhat obviously can be changes in temp, general circulation, precipitation, weather patterns, wind, cloud cover, frequency of "extreme" events, etc.
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MA Rodger at 23:33 PM on 16 March 2013Lessons from Past Climate Predictions: Syun-Ichi Akasofu
I examined Akasofu's work last year as he was being used to support denialist argument presented by the GWPF. Was I being rather generous?
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shoyemore at 19:03 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Ray #36,
Anyone with a feeling for fair play would (I hope) agree that the accusations flung at Marcott over his PhD thesis are shrill and unjust. And also irrelevant.
Ask yourself: Do the contents of Marcott's PhD thesis suggest any grounds for the recent paper to be withdrawn or modified in any way? Who will submit a comment to Science based on a difference in the results of the paper and the thesis?
My answers are "No" and "Nobody".
Theses often end up as papers or books, but in this case Marcott was not "working up" his PhD thesis as a paper, based on Sphaerica #37.
I am glad to see the hysteria over Marcott et al is being mostly ignored by good science blogs. Nor has the paper been accepted without reservation among the climate-change blogging community. If anything, it has been greeted with a proper degree of caution, or real scepticism.
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meher engineer at 18:18 PM on 16 March 2013Death in Jurassic Park: global warming and ocean anoxia
A useful article. A quote that may add to it says, "The oceans act like a sponge to draw down excess carbon dioxide from the air; the gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor. But if CO2 goes into the oceans too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.
That is what is happening now. In a review of hundreds of paleoceanographic studies, a team of researchers from five countries found evidence for only one period in the last 300 million years when the oceans changed even remotely as fast as today: the Paleocene-Eocene Thermal Maximum, or PETM, some 56 million years ago. In the early 1990s, scientists extracting sediments from the seafloor off Antarctica found a layer of mud from this period wedged between thick deposits of white plankton fossils. In a span of about 5,000 years, they estimated, a mysterious surge of carbon doubled atmospheric concentrations, pushed average global temperatures up by about 6 degrees C, and dramatically changed the ecological landscape." It appeared in an article on "Ocean acidification rate mey be unprecedented" (see: http://www.earth.columbia.edu/articles/view/2951), that is worth looking at.
Moderator Response: [DB] The source paper for that article can be found here. -
barry1487 at 18:13 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Sorry about the formatting. :(
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barry1487 at 18:12 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
In fact, perhaps the only individual to actually advocate changing the term from 'global warming' to 'climate change' was Republican political strategist Frank Luntz in a controversial memo advising conservative politicians on communicating about the environment:
It’s time for us to start talking about “climate change” instead of global warming and “conservation” instead of preservation.
“Climate change” is less frightening than “global warming”. As one focus group participant noted, climate change “sounds like you’re going from Pittsburgh to Fort Lauderdale.” While global warming has catastrophic connotations attached to it, climate change suggests a more controllable and less emotional challenge.
I've quoted it once before on SkS; According to Stephen Poole in his book Unspeak..."The U.S., Saudi Arabia, and other oil-producing countries lobbied the U.N. in the late 1980s to change the language of early resolutions from 'global warming' to 'climate change' because the latter is vaguer and less frightening, and also because it doesn’t point the finger so directly at the burning of fossil fuels as the cause. While 'climate change' is scientifically correct (because a local climate might get colder rather than hotter), it obscures the fact that such changes will be a result of the rising mean temperature of the planet — i.e., of global warming."
Poole mentions that part of his book at his blog, here (but there he says the talks occurred in the early 1990s). It's also referenced here. If correct, it might be worth mentioning that everyone who tried to change the language was on the 'skeptical' side of the debate.
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Leto at 16:57 PM on 16 March 2013We're heading into an ice age
Hi there grindup,
I must be having a slow day... Could you spell out the argument for me?
Thanks.
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grindupBaker at 16:45 PM on 16 March 2013We're heading into an ice age
You've all got this backwards on the planning & ethics front. We developed skills over centuries to know that climate will typically go into a very annoying cold state every few thousand years & found that it can be ameliorated simply by burning old rotted vegetables we've found. Instead of leaving most of them for future humans to regulate their climate for a pleasant life, we greedy pigs are taking the whole lot now when it isn't needed. That's an "intergenerational evil" involving very very old rotted vegetables.
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dana1981 at 15:58 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
Did Ray just criticize this post for 'not showing all the data' because it showed a graph with more data than a previous version in Marcott's PhD thesis? It sounds to me like Ray should be directing these accusations at Wattsy.
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dana1981 at 15:53 PM on 16 March 2013Lessons from Past Climate Predictions: Syun-Ichi Akasofu
Matthew, I think you're being rather generous to Akasofu's prediction, which was one of about 0.03°C surface cooling from 2000 to 2013, whereas we've actuallly seen about 0.07°C surface warming despite a preponderance of La Niña events and increased heat storage in the deeper oceans. Even with nature doing everything it can to help him out, Akasofu still hasn't done very well, off by a tenth of a degree after just 13 years.
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Jose_X at 15:01 PM on 16 March 2013Water vapor is the most powerful greenhouse gas
KR and Tom Curtis, I would guess we are probably in agreement that at least within some mostly linear range and to first approximation that the path of deltas/slugs doesn't matter for CO2 and probably also not for most other greenhouse gases. We also probably agree that, in contrast, moving across certain temperatures (eg, hysteresis points) will cause RF calculations to depend on the details of the path taken.
I have a better understanding of this question and will probably consider it more later on rather than sooner, although feel free to keep tempting me back into the conversation if you have something else to add (fyi and if I appear not to return to this thread, my email is hozelda at the yahoo com). Thanks. -
Bob Lacatena at 13:50 PM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
36, Ray,
A skeptical person would have found and downloaded the Ph.D. thesis, and attempted to answer the question for himself, before making veiled implications of impropriety and malfeasance, both on the part of Marcott and Dana.
If you had downloaded the thesis here (sorry, it's rather poorly compressed and 63Mb) you would see that the goal of the thesis was to investigate three longstanding questions of paleoclimatology:
- A longstanding question in glaciology is the nature and mechanism of the so- called “Heinrich events” of the last ~60 ka.
- In the field of glacial geology a longstanding question has been the timing of alpine glacial advances during the Holocene.
- In the field of paleoclimatology a question regarding how global temperature varied over the entirety of the Holocene epoch has remained to be answered for some time.
A brief review of those three goals quickly reveals that the purpose of the original thesis was to answer questions related to climate many thousands of years ago. Current temperatures are obviously irrelevant to that goal, so the graph does not extend beyond what was required.
And yet, as might be expected, Dr. Marcott chose to build upon his previous work and to take it in a new direction, one relevant to a major issue of the day, anthropogenic climate change.
Why is this surprising to you, or to anyone?
But... thank you, because you've added another bit of evidence pertaining to Mr. Watts' denial, and his willingness to intentionally mislead readers such as yourself. He took a perfectly innocuous and pedestrian example of the way science is conducted (do one study, earning one's doctorate, and then build on that work later in one's career) and presented it with implications of nefarious impropriety. Of course, he won't come out and actually make his accusations. He just asks innocent questions like "I wonder what accounts for the difference" (much as you did), then lets that hang in the air like a foul stench.
And you and others fall for it hook, line and sinker.
Maybe, next time, you'll trust Watts less and invest some of your own energy into figuring out how he's led you astray.
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Ray at 11:21 AM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
As this topic is centred on Anthony Watts I visited his website to "have a look for myself". Interestingly the figure you show from Marcott's Science paper, also shown on Watts' blog but not here, is virtually identical to a figure from Marcott's PhD thesis in all respects for the early periods but not for later periods. Notably reconstructions given as negative in the PhD figure are given as positive in the Science paper and even more notably the uptick at the end seen in the Scince paper is absent in the figure from Marcott's Ph.D. Are there any explanations for these discrepancies of which you are aware? I must say I am rather surprised these differences are not mentioned here given your heading "True skeptics consider all the data" .
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Matthew L at 10:27 AM on 16 March 2013Lessons from Past Climate Predictions: Syun-Ichi Akasofu
Oops! My sincere apologies to Mr Akasofu for spelling his name so comically wrong, twice, in the above post.
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Riduna at 10:23 AM on 16 March 2013State Department Downplays the Climate Impact of Keystone XL
The question for the US/Canadian governments is: Should we be stimulating and prolonging the use of fossil fuels or should we be making decisions which decisively move away from their use particularly for transport and electricity generation?
The Canadian government has already answered that question in favor of extending the use of fossil fuels, irrespective of (indeed, by deliberately ignoring) the effects on global warming and the likelihood of destabilising and producing a more extreme climate. A case of money now speaks louder than an assured future. Canada wants a warmer climate.
For the US, the question is can it survive with a rapidly warming environment and an increasingly unpredictable and severe climate likely to seriously impair farm output? For most Americans, logic tells them to go electric for transport and step-up the move to renewables. For vested interests in the oil refining, motor and transport industries its “go Keystone” and God help us if we have to invest in new technology.
God help us if they don’t! But they won’t – not willingly, which is why a final decision by Obama is important. Cling to the past – or move to the future?
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Matthew L at 10:20 AM on 16 March 2013Lessons from Past Climate Predictions: Syun-Ichi Akasofu
I think it is quite possible to spot a pattern and project results into the future based on it without knowing that pattern's cause. For example it had long been established that there was a solar sunspot cycle of approximately 11 years long before the physics was known.
Akafosu thinks he has spotted a 60 year cycle in the temperature data but he does not have an explanation. He has simply projected the data forward as if the cycle he has spotted existed. That is a perfectly valid, if rather limited, thing to do. I am sure the early solar astronomers did the same sort of thing and projected pretty accurately even though the science behind the cycle was unknown, and could not have been discovered with the technology available at the time.
Just because a cause is unknown does not mean that it does not exist, and it is unfair to say that if he is right it is just down to luck. He may have spotted a cycle that the current state of climate science has no explanation for.
Out of interest I have (rather crudely) extended his projection to today against the WfT index below. So far his 'luck' is holding out (or maybe he is correct!).
Support for the 60 year cycle idea is also available from plotting the annual rate of change using long term linear regression analysis. The graph linked to below shows 60 and 30 year linear regression curves for the monthly HadCrut4 data. I used that series because it goes back to 1850.
This seems to support a rough 60 year cycle in the rate of change of temperatures, although it does seem to show accelleration in the rate of change over the last century and a half that Akafasu does not mention. I have put each data point at the centre of the 60 years so that the latest figure is plotted as at 1983. Similarly the 30 year curve is offset -15 years. Currently the 60 year linear regression line shows a rate of change equivalent to just over 1c a century. So where will it go from here?
The graph below superimposes the 15 year linear regression line (centred at -7.5 years). This has taken a steep drop down to a rate equating to around 0.4c a century, a rate not seen since the early 1970s. So unless this 15 year line makes a sudden move in an upward direction (quite possible of course!) Akafasu's projection might carry on being closer to the actual temperature line than the IPCC Model Mean.
Personally I think the CO2 warming signature in this data is in the accelleration in the rate of change rather than the absolute rate at any particular point in time. Just a thought!
I agree with you that this is hardly cutting edge science, more an interesting blog post. As you say, the real science would be finding an explanation for a 60 year cycle in global temperatures. Not one for me, the extent of my expertise is fiddling around with numbers in Excel!
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dana1981 at 10:11 AM on 16 March 2013Watts Interview – Denial and Reality Mix like Oil and Water
shoyeore @34 - it just depends how you define what's an El Niño/La Niña year. My methodology is discussed here.
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