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Bob Loblaw at 12:27 PM on 28 May 2013Medieval Warm Period was warmer
WIlliam Haas: "There is proxy data that shows that for a specific location, temperatures were warmer during the Medieval Warm Period then they are today and man's contribution of CO2 to the atmosphere could not have played a part."
I have direct, anecdotal evidence that it was warmer in my back yard the week before last than all the global warming scenarios ever created predict for the next 100 years. And I'm sure CO2 was not the cause of my back yard being warm.
On the other hand, I don't think that the specific location of my back yard being warm for one short period of time has much to do with global warming due to increased atmospheric greenhouse gases resulting from human burning of fossil fuels over a period of decades.
Perhaps you would actually be willing to provide us with an argument as to why your anecdote is more relevant than mine?
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nealjking at 09:37 AM on 28 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
s_gordon_b:
You wrote:
"Two and 3, by definition, lacked the scope to indicate one way or another whether they support the consensus. Basically, just as most of all of the abstracts that were rated lacked the scope to comment at all on causation; 2 and 3 lacked the scope to comment on the consensus quantification of causation."
That is an interpretation you can assert, but from my involvement and discussion with the study evaluators, I know that they would not have checked off on levels of support 2 or 3 without having come to the conclusion that the abstract was assenting to a support for a significant (not minimal) degree of global warming, due to human influence. They bent over backwards to avoid reading too much support into a statement: Why do you think there are so many neutrals? If the evaluators had been willing to interpret perceived lukewarm support or a tiny perceived impact as 2 or 3, there wouldn't be many neutrals at all.
What you're proposing is a conceivable interpretation of the words in the paper, but bears no relationship to how the evaluators actually worked.
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Tom Curtis at 09:18 AM on 28 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
s_gordon_b @220, you claim that categories 2 and 3 do not support the consensus because:
"Two and 3, by definition, lacked the scope to indicate one way or another whether they support the consensus. Basically, just as most of all of the abstracts that were rated lacked the scope to comment at all on causation; 2 and 3 lacked the scope to comment on the consensus quantification of causation."
First, whether or not the abstracts lack sufficient information to categorize them is irrelevant to the meaning of "endorse AGW". Your argument, if valid, at most shows that categories (2) and (3) should be empty sets.
Seting that argument aside, several cues require us to give "endorse AGW" and "reject AGW" the same meanings where ever they occur in the list of categories. Of these the most important is that if you do not, if you allow "endorse AGW" to mean "endorse the claim that humans have caused most of recent warming" in (1), but "humans have caused at least some part of recent warming" in (2) and (3), then abstracts can logically belong to both categories (2) {or (3)} and category (7) at the same time. Given that the categories are clearly intended to be exclusive, it follows that if "endorse AGW" and "reject AGW" can be interpreted in a way that makes them exclusive it they should be; and that any interpretation that makes them non-exclusive is a misinterpretation. If follows that "endorse AGW" and "reject AGW" must be given the same meaning whereever they occur in the rating system, and that the difference in ratings for endorsements and rejections is a difference not in the level of endorsement (or rejection) but in the clarity of the endorsement or rejection in the abstract.
Several critics of the consensus have bizarrely criticized the paper both on the grounds that both the ratings at different level vary the meaning of "endorse AGW" and that the ratings are inconsistent due to overlap. They do not appear to recognize that by doing so they make their criticism inconsistent. Specifically, they make it clear that they show their criticism to be based on a hostile, out of context interpretation of the ratings and therefore irrelevant.
Leaving that aside, consider how you would rate the following title and abstract:
"On Regional Labor Productivity
Global climate change will increase outdoor and indoor heat loads, and may impair health and productivity for millions of working people. This study applies physiological evidence about effects of heat, climate guidelines for safe work environments, climate modelling and global distributions of working populations, to estimate the impact of two climate scenarios on future labour productivity. In most regions, climate change will decrease labour productivity, under the simple assumption of no specific adaptation. By the 2080s, the greatest absolute losses of population based labour work ability as compared with a situation of no heat impact (11-27%) are seen under the A2 scenario in South-East Asia, Andean and Central America, and the Caribbean. Climate change will significantly impact on labour productivity unless farmers, self-employed and employers invest in adaptive measures. Workers may need to work longer hours to achieve the same output and there will be economic costs of occupational health interventions against heat exposures."
How would you rate it?
It certainly does not ascribe a specific portion of recent warming to anthropogenic factors, so according to your argument it should be rated as neutral (4) at best. It was actually rated as implicitly endorsing AGW (3)*, a rating I agree with because:
1) It explicitly indicates, "Global climate change will increase outdoor and indoor heat loads" (my emphasis), something we have no reason to believe if anthropogenic factors are not the main driver of recent and near future temperature changes.
2) It implicitly endorses the IPCC A2 scenario as a plausible scenario of future temperature evolution; thereby implicitly endorsing the causal connection between greenhouse gases and temperature rise shown in that scenario including the forcing history and relationship to temperature in recent times. That forcing history, of course, shows anthropogenic factors as the cause of greater than 50% of recent warming.
I think the suposition that categories (2) and (3) cannot endorse anthropogenic factors as causing >50% of recent warming is simply wrongheaded, as shown by the example above. Of course any proposition that can be stated explicitly with quantification can also be stated explicitly without quantification by the use of such terms as "most of" (as in "most of recent warming is due to anthropogenic factors") or "dominant" (as in "the dominant cause of recent warming has been anthropegenic factors"). Further, anything that can be stated explicitly can be stated implicitly by leaving part of the affirmation to background information.
In the end, your objection comes down to the claim that it is easier to make mistakes about categories (2) and (3) than category (1). As the endorsement becomes less explicit and precise, it becomes easier to mistake endorsement for a neutral paper, and vise versa. That, at least, is true. Given the comparison between abstract rated and self rated papers, however, the mistakes have overwelmingly been conservative so the papers conclusions stand.
*One of the author's of the paper has rated it as neutral (4), but in ongoing comments he has shown that he does not understand the rating system by indicating that he thinks there is a "luke warm" category (which is clearly a mistake), and implicitly endorsed a claim by a well known "skeptic" that the consensus position is that "... almost 90-100% of the observed global warming was induced by human emission", which is absurd given the actual statements from the IPCC. It follows that the author (Richard Tol) is so confused about what is being endorsed and the rating system that his self ratings are irrelevant. I discuss his claims further on my blog.
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Tom Dayton at 09:10 AM on 28 May 2013Medieval Warm Period was warmer
William Haas, read the Intermediate tab of this posting, and take special note of the description of the "seminal paper on this subject." Click that phrase on that page to get to the details. It is irrelevant that as you wrote "for a specific location" temperatures were warmer than today. "Global" warming means more than one specific location, and there was no synchronized global Medieval Warm Period. So your vague contrarian speculation is irrelevant; you are speculating about a non-event.
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Rob Honeycutt at 08:51 AM on 28 May 2013Medieval Warm Period was warmer
William Haas... No one claims that man-made CO2 had any effect during Medieval times. There are, though, other known factors at play during that period, including increased solar activity and low volcanic activity. But, overall, it is estmated that current global temperature is likely as high or higher than the MWP. This in spite of the fact that the planet has been on a 5000 year orbitally forced trend toward generally cooler conditions.
Currently there is no other rational explanation for the temperature trend since modern industrialization other than increased levels of man-made greenhouse gases.
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William Haas at 08:37 AM on 28 May 2013Medieval Warm Period was warmer
Estimates of global temperatures during the Me devil Warm Period are somewhat speculative because we do not have direct measurements of global temperatures dating back that far. There is proxy data that shows that for a specific location, temperatures were warmer during the Medieval Warm Period then they are today and man's contribution of CO2 to the atmosphere could not have played a part.
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Tom Curtis at 07:44 AM on 28 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
s_gordon_b @221, try searching for the terms " " (ie, a single space) or "i" for a generalized search.
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s_gordon_b at 07:09 AM on 28 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
JasonB,
I wrote: "I still don't see how I can use that page to get those figures."
D'oh. I mistook the search page for the "rate abstracts" page. It does insist you enter a search term, though, which limits the results.
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s_gordon_b at 06:42 AM on 28 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
Hi JasonB,
You wrote in reply to my post:
Perhaps it would be easier to understand your point if you could point us to some examples of where the study is being spun?
Ironically, in light of the methodology of the paper, the spin (more neutrally, I should call it confusion or conflation) starts with my "rating" of where Cook et al.'s abstract stands on AGW (emphasis below is mine):
"We analyze the evolution of the scientific consensus on anthropogenic global warming (AGW) in the peer-reviewed scientific literature, examining 11 944 climate abstracts from 1991–2011 matching the topics 'global climate change' or 'global warming'. We find that 66.4% of abstracts expressed no position on AGW, 32.6% endorsed AGW..."AGW is immediately defined as "the scientific consensus on anthropogenic global warming," not in the broadbrushed, imprecise, popular way that ranges from "we're a significant contributor, along with natural causes" to "we're the cause." In the next breath, we're told that "32.6% endorsed" that consensus. Ask anyone who reads climate science papers what the term "scientific consensus on anthropogenic global warming" means in the context of such a paper, and how many will say "simple: humans are a significant cause of global warming" vs "it refers to the consensus of the IPCC and pretty much all of the other major scientific review bodies that humans are the dominant (if not the only) cause of global warming, at least since the 1950s"? In climate science circles "consensus" has a precise meaning. And this is a climate science paper. This is why when I initially read about the paper - and based on my very high level of trust in SkS - I took the claim about support for "the consensus" literally, in the IPCC sense, and represented the paper that way on social media. It's also why I was stunned when I actually read the paper and got to the part where categories 1, 2 and 3 were rolled up together and rated as "the consensus." Not so. Two and 3, by definition, lacked the scope to indicate one way or another whether they support the consensus. Basically, just as most of all of the abstracts that were rated lacked the scope to comment at all on causation; 2 and 3 lacked the scope to comment on the consensus quantification of causation.
You continued:
Regarding the authors, again, they were asked to state whether each specific paper endorsed the proposition that anthropogenic GHGs are causing global warming, rejected the proposition that anthropogenic GHGs are causing global warming, or was neutral. If the author of the paper felt that their paper implied humans were having a minimal impact on global warming (e.g. by proposing an alternative as the main cause of global warming), or stated that human impact was minimal or non-existent, or stated that humans were causing less then half of global warming, then they would have categorised their own papers as rejecting the proposition.
I'm fairly confident that anyone who rejected the consensus view would have made damn sure their paper was counted as a rejection if it was at all possible to do so! And let's not forget that the authors of any papers who feel their paper should have been counted as a rejection are free to search for their paper in the results and alert us to the miscategorisation.
You're misunderstanding my argument. I'm not in any way suggesting that minimizing or denying papers were lumped into the "endorsing"/consensus-supporting abstract count. For example, if I wrote a paper that (to quote from the choices the authors were given) "... explicitly states humans are causing global warming or refers to anthropogenic global warming/climate change as a given fact," I would concur if it was rated as category 2. Likewise, I would concur with a category 3 rating if my "paper implies humans are causing global warming. E.g., research assumes greenhouse gases cause warming without explicitly stating humans are the cause." But I would concur in both these cases even if my paper had zero to say for or against the IPCC consensus on degree of causation. Indeed, if my paper had supported the consensus, I would have rated it 1.
Anyway, the bottom line is that the authors of 97.2% of the papers that took a position stated that their papers endorsed the proposition that anthropogenic greenhouse gasses are causing global warming. That's it.
Exactly. They "endorsed the proposition that anthropogenic greenhouse gasses are causing global warming." "Are causing" can be read the same way as "obesity is causing Type 2 diabetes": it's a contribuitng cause. But, again, only a fraction of the papers were designed to endorse or reject the dominant cause IPCC consensus implied in the abstract and in all manner of coverage that has followed. E.g.:
From the lead in Suzanne Goldberg's story in The Guardian (http://www.guardian.co.uk/environment/2013/may/16/climate-research-nearly-unanimous-humans-causes):"A survey of thousands of peer-reviewed papers in scientific journals has found 97.1% agreed that climate change is caused by human activity."
When I write (as a journalist) or read "is caused by" in the context of the climate change social debate (it is a debate, in civil society; otherwise there would be no need for this paper and the Consensus Project), my meaning/understanding is primary causation, if not "the cause."
There's no shortage of argument on this board about the semantics used in the study and surrounding it. Cook et al. could simply address this by releasing a clarification, unless they really believe it's scentifically sound to infer that category 2 and 3 papers do endorse the consensus. Alternately, they could go through all their past writings and redefine their use of the word consensus to mean that human activities are at least a significant contributor to global warming.
Quoting and answering me:
*I've looked everywhere, but I can't find where the numbers of abstracts assigned to each of the original Table 2 categories is or the category assignments by the study authors. Could you point me to that data?
http://www.skepticalscience.com/tcp.php?t=search
I had already gone there. I still don't see how I can use that page to get those figures. Why isn't the data simply published somewhere? It's such basic information for people who want to understand the study's findings.
Perhaps you should spend some time reading the earlier comments to avoid rehashing the same points over and over again.
I read plenty and found little beyond arguments about semantics. But now you've provided me numbers for category 1 in your earlier post, where you write:
... of interest to this discussion is the breakdown between papers that quantify the human contribution to global warming as >= 50% and papers that quantify the human contribution to global warming as < 50% (i.e. levels 1 and 7), since there is no interpretation required for those. The former represent 88% of all papers that quantify the human contribution to global warming (64 of 73).
I think you've made a fundamental error here. For a paper to unambiguously support the IPCC et al. consensus, it does indeed have to fall into category 1. But for a paper to unambiguously reject or deny it, it only has to fall into category 5, 6 or 7. That's 0.7 of 11,944 papers = 84 (maybe a few more, judging by the responses to some to the queries Popular Technology sent to known anti-AGW scientists whose papers had been rated). So the proper comparison, it seems to me, is 64 vs 84 or 64 out of 148 explicitly, unambiguously endorsing vs rejecting the IPCC consensus.
For me, the lesson of this study is that it's very hard to find robust support for the IPCC consensus just by doing a head count of papers on climate change, because very few papers, so far at least, have explicitly (or implictly, I suppose) sought to test that quantified consensus. Maybe this is analogous to the relationship between any large body of literature and the relatively uncommon major reviews and meta-analyses that attempt to put it all together and draw those larger conclusions of which consensuses are made.
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John Hartz at 06:21 AM on 28 May 2013A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Also see:
Cassano, E. N., Cassano, J. J., Higgins, M. E. and Serreze, M. C. (2013), Atmospheric impacts of an Arctic sea ice minimum as seen in the Community Atmosphere Model. Int. J. Climatol.. doi: 10.1002/joc.3723
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Rob Painting at 06:08 AM on 28 May 2013Uncertainty no excuse for procrastinating on climate change
Kev, my bad. And I did read the paper! Mind you the first sentence in the paper is misleading.
It's not easy tracking down all the sources for their inputs into the calculations, but their choice of climate forcing seems to be the clincher. The use of the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) forcing moves the equilibrium climate sensitivity back up to 2.4°C - closer to the central estimate using other methods.
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John Hartz at 05:32 AM on 28 May 2013Land Surface Warming Confirmed Independently Without Land Station Data
Dana,
Your "Note" at the end of the OP needs an edit.
Also, shouldn't the rebuttal article, It's Urban Heat Island effect also be updated in a similar manner?
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william5331 at 04:55 AM on 28 May 2013A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
R. Gates (18)
There is another phenomenon that is likely. When low pressure systems sidle up to the Atlantic side of Greenland, they induces katabatic winds down the flanks of Greenland. Presumably the same will happen if a low can get close to the northern coast. All that is necesary is for the ice to disappear. The ice shelf tends to hold low pressure areas off the coast and weaken them. Katabatic warming for descending air (no dew point involved as is the case with rising air) is 9.8 degrees per vertical km. From the very peak of Greenland to the coast is over 3km or about 300C. With a hurricane such as the one that we had Aug6, 2012, we should see some serious surface melting.
http://mtkass.blogspot.co.nz/2012/11/greenland-melting.html
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MA Rodger at 02:54 AM on 28 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years?
I continue my game of cosmological Where's Wally by crossing the Atlantic. The US Eastern seaboard stretches 1,500 miles so can provide a regional temperature by averaging a set of State data from NCDC, Maine, Massachusetts, Maryland, N Carolina & Florida being chosen. They have a very similar temperature record as shown in the tiny inset graphic. (The anomaly base 1895-1945 is probably the reason for the particularly close match during those years.)
The contiguious ocean SST from nomad3 were taken as 25-45N, 70-80W. (This isn't the most representitive part of the Atlantic SST-wise, lacking signs of warming 1981-date.) AMO is after Enfield.
The first graph shows the land & adjacent ocean temperatures 1981-date do have certain similarities but with warming only evident on land. Also, if the larger wobbles match up, they appear a month or so earlier on land, which is not good for any theory of AMO as a driver of land temperature.
The second graph attempts to compare those US temperature records with AMO over a 120 year period. I see there no evidence of AMO warming the Eastern coast of the USA over that period.
So where is Amo hiding?
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MA Rodger at 02:49 AM on 28 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years?
So where to look for evidence of AMO warming affecting climate beyond the shores of the N Atlantic?
My first thought was that if AMO was going to effect temperatures anywhere, it would be the UK. Indeed, the CET was invoked within T&Zh13. So I compared CET with the SST for the surrounding seas (45-65N, 20W-10E) with nomad3 providing monthly SST data - 1981 to date. The two temperature profiles are re-based for comparison and graphed below. with AMO also plotted (although AMO is of course subject to a de-trending).
The divergent record is evidently CET not the SST which suggests that during these divergent periods, AMO is not in any way a dominant influence in CET. So are divergent periods infrequent such that the period 1988-2004 is the norm where SST & CET can be married together?
A de-trended CET for the period of Enfield's AMO index (1856 to date) is next up for comparison being graphed below. Divergence appears the normal state here, with the two indices have little in common. I would conclude that the CET record does not support the suggestion that AMO drives UK temperatures.
Still. It's early days. There may yet be that local variation is swamping the signs of the AMO driving UK temperatures. And the UK is not the whole globe.
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MA Rodger at 02:39 AM on 28 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years?
Apologies for the non-functioning links @64 & @65 & thank you DB for providing links.
I feel the extra palaver of linking to view the graphics is a step too far so will attempt to find a host for the graphics that will allow on-page viewing.
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Daniel Bailey at 01:30 AM on 28 May 2013Cherrypicking to Deny Continued Ocean and Global Warming
@ matzdj
About that 1970s ice age prediction:
This meme stems originally from a 1971 Rasool and Schneider study, which was predicated on a quadrupling of aerosol emissions; this possible pathway never happened.
Emissions actually went the opposite trajectory due to the establishment of the EPA and the Clean Water Act in 1970, the Vienna Convention on the Protection of the Ozone Layer of 1985, the The Montreal Protocol on Substances that Deplete the Ozone Layer of 1987 and the Clean Air Act of 1990.
http://www.sciencemag.org/content/173/3992/138
http://www.epa.gov/ozone/intpol/The meme originates with a 1974 Time article and a 1975 Newsweek report.
http://www.nationalcenter.org/Time-Ice-Age-06-24-1974-Sm.jpg
http://denisdutton.com/newsweek_coolingworld.pdfHowever, those are media articles, not scientific studies. A survey of peer reviewed scientific papers from 1965 to 1979 show that few papers predicted global cooling (7 in total). Significantly more papers (42 in total) predicted global warming (Peterson 2008). The large majority of climate research in the 1970s predicted the Earth would warm as a consequence of CO2. Rather than 1970s scientists predicting cooling, the opposite is the case.
http://ams.confex.com/ams/pdfpapers/131047.pdfSo only the alarmists still perpetuate the "70s Ice Age" meme, FYI.
Please do a better job of staying on-topic in this thread; thanks.
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Daniel Bailey at 01:22 AM on 28 May 2013Cherrypicking to Deny Continued Ocean and Global Warming
Occasionally, scientific ideas (such as biological evolution) are written off with the putdown "it's just a theory." This slur is misleading and conflates two separate meanings of the word theory: in common usage, the word theory means just a hunch, but in science, a theory is a powerful explanation for a broad set of observations. To be accepted by the scientific community, a theory (in the scientific sense of the word) must be strongly supported by many different lines of evidence. So biological evolution is a theory (it is a well-supported, widely accepted, and powerful explanation for the diversity of life on Earth), but it is not "just" a theory.
Words with both technical and everyday meanings often cause confusion. Even scientists sometimes use the word theory when they really mean hypothesis or even just a hunch. Many technical fields have similar vocabulary problems — for example, both the terms work in physics and ego in psychology have specific meanings in their technical fields that differ from their common uses. However, context and a little background knowledge are usually sufficient to figure out which meaning is intended.
http://undsci.berkeley.edu/article/howscienceworks_19Below is a generalized sequence of steps taken to establish a scientific theory:
1. Choose and define the natural phenomenon that you want to figure out and explain.
2. Collect information (data) about this phenomena by going where the phenomena occur and making observations. Or, try to replicate this phenomena by means of a test (experiment) under controlled conditions (usually in a laboratory) that eliminates interference's from environmental conditions.
3. After collecting a lot of data, look for patterns in the data. Attempt to explain these patterns by making a provisional explanation, called a hypothesis.
4. Test the hypothesis by collecting more data to see if the hypothesis continues to show the assumed pattern. If the data does not support the hypothesis, it must be changed, or rejected in favor of a better one. In collecting data, one must NOT ignore data that contradicts the hypothesis in favor of only supportive data. (That is called "cherry-picking" and is commonly used by pseudo-scientists attempting to scam people unfamiliar with the scientific method. A good example of this fraud is shown by the so-called "creationists," who start out with a pre-conceived conclusion - a geologically young, 6,000 year old earth, and then cherry-pick only evidence that supports their views, while ignoring or rejecting overwhelming evidence of a much older earth.)
5. If a refined hypothesis survives all attacks on it and is the best existing explanation for a particular phenomenon, it is then elevated to the status of a theory.
6. A theory is subject to modification and even rejection if there is overwhelming evidence that disproves it and/or supports another, better theory. Therefore, a theory is not an eternal or perpetual truth.
http://www.oakton.edu/user/4/billtong/eas100/scientificmethod.htmFor a good discussion of science terminology (especially for the "Evidence, not Proof" bit), see here:
http://evolution.berkeley.edu/evosite/footshooting/Iterminology.shtmlAnd speaking of NASA again:
http://climate.nasa.gov/key_indicators
http://climate.nasa.gov/evidence/
http://climate.nasa.gov/causes
http://climate.nasa.gov/effectsWhich brings us full-circle to matzdj's comment sparking this line of discussion: anthropogenic climate change (ACC)/anthropogenic global warming (AGW) is indeed a theory. In reality, the National Academies of Science refer to it as "settled fact" instead of a scientific theory.
Per the National Academies of Science, in their 2010 publication Advancing The Science Of Climate Change (pp 44-45):
"Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small.
Such conclusions and theories are then regarded as settled facts.
This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities."
http://www.nap.edu/catalog.php?record_id=12782
And note that the above National Academies paper is available for free download after a free registration. No purchase necessary. And the quote is from pages 44 & 45.
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Kevin C at 01:05 AM on 28 May 2013Cherrypicking to Deny Continued Ocean and Global Warming
matzdj: The point of this site is that there is a huge amount of misinformation concerning climate.
While to a casual observer it may look as though there are two balanced sides both arguing that the other is wrong, if you spend a little time comparing secondary sources against primary sources, I think you will very quickly spot a pattern and be able to draw some conclusions about what is going on. As a starting point, let me pick a couple of examples from your post:
No question we are hotter now than in the 1970's (when climatologists were predicting a coming ice age)
What is the basis for your belief that climatologists were predicting an ice age in theh 70's? Is there documentary evidence? Was it a widespread view?
but the monotonic correlation with CO2 does not correlate, except over a long term.
Does climate science predict a correlation with CO2 over the short term, or are the other factors which can affect short term trends? Do we know what these are?
Have any of the models predicted this stair-step climb of temperature? If none do, then maybe they are missing a driver or incorrectly including it.
Good question. Have you attempted to answer it? ('Hiatus decade' may be a useful search term if you are stuck.)
Is there any Experimernt, or any observation, that could occur that might lead the "settled science" folks to say, "We should look at that. We might be wrong".
Plenty. Here's just one to start with: If the Earth's IR spectrum as observed from space did not show CO2 absorbtion lines which broaden as we increase the CO2 concentration in the atmosphere, we would throw out climate science straight away.
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Tom Dayton at 00:47 AM on 28 May 2013Cherrypicking to Deny Continued Ocean and Global Warming
matzdj, are you saddened by the overwhelming evidence that gravity exists? I don't know what field your PhD is in, but in science part of the definition of "progress" is that intentionally varied evidence converges on a picture of reality, because reality constrains the evidence. Scientists are motivated to show that all other scientists are wrong--that the consensus is incorrect--because that path leads to fame and personal pride and a feeling of accomplishment and contribution. So scientists leap on evidence that appears to contradict the consensus. But reality always eventually wins, as apparently contradictory evidence is refined until it reveals the truth.
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matzdj at 23:46 PM on 27 May 2013Cherrypicking to Deny Continued Ocean and Global Warming
Every time I try to review information on this site, I always come away with the sad feeling that 100% of the data interpretations that might lead to some conclusion other than anthropogenic CO2 caused Global warming are wrong. That can't be.
Both sides do have legitimate scientists on them (more on the CO2-is-the-ogre side), but there is no legitimate way that every statement that either side makes can be wrong. (-snip-).
When it comes to the escalator effect, different data sets show somewhat different effect. The GISS data that I have seen seems to show a steady average Global T from 1970 to the early 1990's, a substantial step from the early 90's to the early 2000's and a relatively steady average from then until now.
No question we are hotter now than in the 1970's (when climatologists were predicting a coming ice age), but the monotonic correlation with CO2 does not correlate, except over a long term.
If we assume that the CO2 driver is the main driver in the background, where is the analysis of all other factors that cause no net temperature climb over these relatively flat periods with step changes when the sub-drivers stop neutralizing the CO2 effect. (-snip-).
Have any of the models predicted this stair-step climb of temperature? If none do, then maybe they are missing a driver or incorrectly including it.
Is there any Experimernt, or any observation, that could occur that might lead the "settled science" folks to say, "We should look at that. We might be wrong". If there is nothing that can ever prove that your theory is wrong, than it is not a scientific theory. it is just a belief.
Some day I would like to see a fair and balanced discussion on data linking CO2 to warming and on alternative potential drivers to global warming, rather than this constant barrage of why the other guys are 100% wrong?
David J Matz, PH.D
Moderator Response:[DB] In order to make best usage of what this site has to offer, you need to use the Taxonomic listing of arguments and the Search Function (located in the UL section of every page). Discussions of the intricacies you express interest in are best conducted on those specific threads.
For example, your claims about data interpretations might be answered by reviewing the Big Picture article and following the links as needed from there.
Discussions of the Escalator and its permutations are best done here.
For CO2:temperature correlations, see here.
CO2 is not the only driver of climate
Models are not necessarily as unreliable as you think
As for your theory vs belief, I will place a separate comment about that, as a proper response lies outside the aegis of this function.
Off-topic/sloganeering snipped.
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Kevin C at 23:37 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Rob: Otto et al looks at the following temperature differences:
- mean(2000...2009) - mean(1860...1879)
- mean(1990...1999) - mean(1860...1879)
- mean(1980...1989) - mean(1860...1879)
- mean(1970...1979) - mean(1860...1879)
These are compared to the change between the two periods in either forcing or (forcing-uptake) for TCR or EffCS. The trends within those periods do not appear anywhere in the calculation. Uptake is assumed to be 0 for the early period - i.e. the ocean is assumed to be equilibriated.
There is a copy of Otto et al online here. It's worth reading what the paper actually says, because it bears little resemblence to what most secondary sources say the paper says.
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chriskoz at 19:55 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Rob@8,
I concur with your doubts. David Keith looks to me as the guy who cares about the mythical limitless growth only rather than sustainability. Not even mentioning his perpetually-moving optimism about the law of thermodynamics. I wonder why the interviewer on this YT video didn't ask for that, I would have pressed the guy here and won't let him evade it.
I think the climate change due to athmosphere being treated as CO2 dumping ground is part of even larger problem facing overpopulated earth: complete disregard on sustainabily principles by the ravaging homo "sapiens". This larger context is not to be ignored, because even if we solve/stabilise CO2 problem soon, we may end up exposing another, equally alarming environmental degradation problem.
Meanwhile it's worth remembering This article + comments, which apears to be the latest SkS stance on this topic.
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Rob Painting at 18:26 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Shoyemore - I understand one of the Skeptical Science authors has volunteered to write about the Myles Allen piece. I'm not sure how he plans to overcome the laws of thermodynamics with this carbon capture scheme. Has the hallmarks of perpetual motion machine crankery about it.
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shoyemore at 17:48 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Professor Myles Allen (one of the authors of the Otto study) has written a strange article in that rag, the Daily Mail, advocating a new departure to seriously research carbon capture and sequestration (CCS). Naturally, the Mail distorts his views in its headline (and you could almsot say it serves him right!:))
Others have been writing about this lately, like the physicist Laurence Krauss in Slate, and Dr David Keith of the University of Calgary.
www.youtube.com/watch?feature=player_embedded&v=PilKYZ_VVnc
CCS proposals like Allen's will probably used to justify more procrastination, of course.
Perhaps Skeptical Science could so a full post on this, or even re-post Allen's article for discussion. I am sure he would agree.
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Rob Painting at 17:02 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Kevin - that makes no sense. How can they calculate the transient climate response (TCR) and equilibrium climate sensitivity (ECS) without feeding in the change in (near-surface air) temperature for each period? Change in (surface) temperature is an essential input into the equation.
In figure 1 of Otto (2013) they even give a break-down of TCR and ECS for each decadal period - from the 1970's to 2000's.
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Kevin C at 15:12 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
A recent study by Alexander Otto of Oxford University and colleagues, published in the journal Nature Geoscience, also considered future global warming in the context of observations of global mean temperature change over the last decade.
I'm puzzled by this sentence, since it seems to be based on the BBC's misrepresentation of the Otto paper, rather than what the Otto paper actually says.
The Otto paper is not based on temperature changes over the last decade - in fact Otto et al totally ignore changes over the last decade (except in OHC). Instead they take the average temperature over the last decade (and also the previous 3), and compare it to the average of a baseline period from 1860-1880. And the last decade does not stand out in any way - they find similar results for the 00's, the 90's, and the 80's. This part of the calculation is trivially reproducable.
Otto et al is not without it's limitations:
- HadCRUT4 only covers 5/6 of the planet even in recent decades. My best estimate is that this causes them underestimate the temperature change by 5%, although the global temperature distribution for the 1860s is based in totally inadaquate information and so I'm guessing this number should be closer to 10%.
- They note in the text that they are calculating effective climate sensitivity, which provides a lower bound for equilibrium sensitivity. They reference Armour et al, which finds that the effective sensitivity is about 15% lower than the equilibrium sensitivity.
If correct, these two factors alone would bring the Otto ECS to 2.4C, which is much more plausible, however the EffCS-ECS correction is currently based on only one paper (and my coverage work is not published at all). Until this is better constrained I wish they would be a bit clearer about the distinction between EffCS and ECS.
The method from the Otto paper is also totally dependent on the size of the forcings. They use forcings from this paper by Forster et al which looks very interesting indeed. I would like to try this data in my response function model.
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jyyh at 13:58 PM on 27 May 2013A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
ulisescervantes: "negative AO, if associated with Arctic warming, tends to mitigate the (very strong) positive feedback of extra cloudiness."
This at least goes well with the ages old weather proverb (on lake ice) from Finland that states (translation):"clear skies, strong ice, icing with snow, on ice don't go". I don't know how well this applies to salty sea ice, though.
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Tom Curtis at 13:56 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
tonyabalone @3, agreed about The Australian's publications of letters. I have never had one of my letters pointing out (even subtely) their constant misrepresentation of the science actually published. I'm now trying a new tactic. I just sent of my email complaining about the article, but copied it to David Karoly and mediawatch (mediawatch@your.abc.net.au. Perhaps the knowledge that they cannot simply disappear the email will encourage them to publish. And if not, perhaps mediawatch will take an interest.
Who knows?
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tonyabalone at 13:49 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Tom Curtis @ 2 yes I suspect that you are correct that the paper has been bombarded with complaints. I fired off an email to the editor compaining about the misinformation in the article. It won't be published of course. Limited News is very careful about their image and they don't take kindly to criticism, even when they know it is justified.
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Tom Curtis at 13:37 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
tonyabalone @1, the Australian is schizophrenic on this study. In print the headline the article "Scientists now expect 2C rise", which is doubly misleading. First because it lacks the words "at least", and second because it suggests this is news, ie, that scientists have not been expecting at least a 2 C rise since about 1990.
The then state (as you point out):
"The earth's temperature is unlikely to increase by more than 2C by 2100 - significantly less than earlier predictions - assuming carbon dioxide emissions are substantially reduced."
This contrasts sharply with the abstract of the study which states:
"This results in an increased probability of exceeding a 2 °C global–mean temperature increase by 2100 while reducing the probability of surpassing a 6 °C threshold for non-mitigation scenarios such as the Special Report on Emissions Scenarios A1B and A1FI scenarios6, as compared with projections from the Fourth Assessment Report7 of the Intergovernmental Panel on Climate Change."
(My emphasis)
The abstract does not discuss scenarios with substantially reduced emissions at all.
The in print article goes on to say:
"The results are based on a scenario in which action is taken to mitigate emissions, though no reduction target is specified. It says under a 'business as usual' approach, temperatures are likely to rise by more than 2 C."
Well, I guess 4 C (the expected rise under BAU) is more than 2 C, so it is not exactly a lie - but hardly informative.
In contrast, the online version of the Australian leads with:
"Doubt will remain on climate
BY:MITCHELL NADIN From: The Australian May 27, 2013 3:00AMSCIENTISTS have narrowed the range of possible global temperature rises due to greenhouse gas emissions, but say uncertainty will always remain because of the complexity of factors in climate change.
Research conducted at the Melbourne University, and published today in Nature, found previous estimates of a 6C rise in temperatures by 2100 were "unlikely", but that exceeding a 2C change was "very likely" given business-as-usual emissions."
Same author, same study, different title and a balanced if much truncated text. Oddly, that article is listed as being posted "1 hour ago", ie, 12:30 PM AEST, not the 3:00 AM listed under the byline. My guess is that complaints were made about the transparent and misleading bias of the inprint article, resulting it being pulled online and a better version substituted. Without, of course, any admission of error.
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tonyabalone at 13:03 PM on 27 May 2013Uncertainty no excuse for procrastinating on climate change
Sadly "The Australian " newspaper today (27 May) was up to its usual trick of misrepresenting the science by stating in the opening sentence "The earth's temperature is unlikely to increase by more than 2C by 2100.." whereas the authors are clearly saying that "exceeding 2C is virtually certain." This is typical of the Murdoch press as they continually put the best face on the climate science even if it means that publishing misinformation.
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chriskoz at 11:53 AM on 27 May 20132013 SkS Weekly Digest #21
Toons are getting better and better!
I thought the one from last weeek was hard to beat but this week is also excellent. And sadlyvery realistic, as news popup about arctic drilling opportunities following receding ice.
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Tom Dayton at 09:54 AM on 27 May 2013Has the rate of surface warming changed? 16 years revisited
I agree with jdixon1980 and Dumb Scientist: Why the heck do climate scientists refer almost exclusively to atmospheric temperature with the words "global temperature" in press releases, interviews, and even sometimes abstracts, without an emphasized disclaimer that atmospheric temperature is not even remotely close to the real global "temperature"--that is, total thermal content? Often the scientists even say publicly that "global warming has slowed" or "paused" or is on "temporary hiatus" when they know perfectly well that it most certainly is not when you properly consider the total energy content.
I asked that of James Hansen last week in his talk at NASA Ames Research Center, but I did not phrase the question clearly enough. He answered that you do not even need to do that, because even surface atmospheric temperature has not paused in its increase; it has merely not been increasing as much as it was in the decades before, and that is entirely expected variability. I think that retort is too technical for most of the public. I think it is much easier for the public to understand that the "temperature" of the entire system must be what is monitored, and clearly it has not stopped increasing. (By the way, Hansen's talk is available online on UStream.)
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Tom Dayton at 09:15 AM on 27 May 2013It's not bad
New NASA study accepted by Geophysical Research Letters (Lau et al.) quantifies that wet places will get wetter and dry places will get drier--more floods and drought. Heavy rain will increase, light rain will increase slightly, but moderate rain will decrease and no rain will be more frequent. There is a summary with video of global map of changes.
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Steve J at 08:10 AM on 27 May 2013Ivar Giaever - Nobel Winning Physicist and Climate Pseudoscientist
Needs a place on the page "Climate Misinformers"?
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Dumb Scientist at 02:27 AM on 27 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years?
I wanted to thank Dikran again for his contribution. It inspired my own simulation, which has better formatting here.
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ulisescervantes at 20:11 PM on 26 May 2013A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
Excellent article, thanks. Yet, I wanted to note something: arctic clouds during fall-winter-spring have a net heat-trap effect. At the same time, these periods of very negative AO, that happened in recent years between fall and spring, are synonymous of sustained high pressure (and correct me if I'm wrong, cloud-free skies) over the Arctic. It sems that negative AO, if associated with Arctic warming, tends to mitigate the (very strong) positive feedback of extra cloudiness. Any thoughts?
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garethman at 18:31 PM on 26 May 2013A Rough Guide to the Jet Stream: what it is, how it works and how it is responding to enhanced Arctic warming
What a cracking good article. It clerared up a lot of questions I had regarding this issue, especially due to living in Wales where the jet stream almost rules our lives.
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Bernard J. at 13:58 PM on 26 May 2013On the value of consensus in climate communication
Anyone who has any doubt about the practical utility of Cook et al should consider that the Australian conservative opposition leader, Tony Abbott, has used ambiguity about a scientific consensus to publicly question the very existence of climate change. Many of his senior (and junior) party members, and a number of high-profile conservative media commentators, are even now at least as inclined to use this stratagem to stir up public doubt.
This action was one of several that were employed by conservatives and that led to a very significant delay of action in Australia in addressing the effects of human emissions. It has in fact effectively tainted the political landscape of Australia since 2010, when its consequences amongst the general public contributed significantly to Kevin Rudd shying away from action and Julia Gillard grasping the reins from him.
The next (and already evident) approach by the conservatives will be to acknowledge that climate change is happening, and that it was accepted by a consensus of scientists, but that it is not nearly as dangerous as scientists are warning. It's just the next gambit in the list of denialist responses that many of us have been discussing for years. A useful follow-up to Cook et al would be to conduct a similar survey investigating scientific understanding of and thoughts on the full spectrum of consequences and impacts of human-caused climate change. Last year in an idle moment I even sketched an outline for such a survey, including questionaire design and methodological rationale and approaches such as stratification for professional and personal cofactors.
Now that would be a study that would be of great interest to me, and no doubt to many others...
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KK Tung at 13:43 PM on 26 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In reply to KR at post 83 and originally at post 14 on the Anderson et al 2012 paper: It was claimed by KR that this paper has ruled out the possibility of more than 10% of the observed warming as contributed by natural variability. I am delinquent in replying to this thread.
Nothing of the sort--- that sets an upper limit of 10% as contributed by natural variability as claimed--- can be concluded from the model results.
Unlike the papers of Meehl et al that I discussed in post 113, the models used in Anderson et al are atmosphere-only, and are incapable of generating internal variability involving ocean dynamics. Through clever experimental design, the authors were able to place some constraints on the magnitude of unknown internal variability, and showed consistency within models which simulated well the observed warming of the late 20th century as almost entirely forced. In the first simulation, the observed sea-surface temperature (SST) in 1950-2005 is specified but with no greenhouse gas forcing or any other atmospheric forcing. In the second simulation, known atmospheric forcing such as greenhouse gases, tropospheric sulfate aerosols, tropospheric ozone and solar variations are added to the first. In third simulation, there is no change in SST. The atmospheric radiative forcing is the same as the second simulation. Five ensemble members are run for each experimental setup. The top-of-the atmosphere radiative imbalance is assumed to be the same as what should have been going into the (missing) ocean as change in ocean heat content. This is a reasonable assumption. The second simulation should give the radiative imbalance produced by known radiative forcing agents and the observed historical SST. This imbalance was compared with the ocean heat content change and was found to be in good agreement. The ocean heat content change was estimated using Levitus et al’s data up to 2008, and down to about 700m. It was assumed that this is 70% of the total ocean heat content, as the latter was not in the data. Possible errors associated with this one assumption alone already could exceed 10%. (This is however not my main argument.) The rest of the paper went on to argue why there is no room for more than 10% contribution from other unknown radiative forcing agents.
The model result should be viewed as a consistency test of the hypothesis proposed. As I mentioned in my previous posts, most CMIP3 models succeeded in simulating the observed warming in the second half of the 20th century as forced response using known radiative forcing agents with the magnitudes that they input into their models. If, as we argued in our paper and in part 1 of my post, the tropospheric aerosol cooling, which is uncertain, was underestimated, there would be a need for the presence of internal variability that warms during the second half of the 20th century. The authors acknowledged the possibility of two alternative hypotheses that were not tested by their work: My comments in bold below.
It should be noted that….there are two alternate, untested hypotheses. One is that the known change in total radiative forcing over the last half of the twentieth century … is systematically overestimated by the models (yes, that is our hypothesis) and that the long-term observed changes in global-mean temperatures are instead being driven by an unknown radiative-forcing agent(the unknown agent is the additional tropospheric sulfate aerosol cooling). The second hypothesis is that the global-scale radiative response of the system … is systematically underestimated by the models (equivalently the climate sensitivity is systematically overestimated) (I do not intend to argue that the climate sensitivity should be lower than used by the models, and so this is not the hypothesis that we pursued)…. However, for either of these two alternate hypotheses to supplant the current one (i.e., that known historical changes in total radiative forcing produced the observed evolution of global-mean SSTs and ocean heat content), the unknown forcing agent would need to be identified(we have identified it), changes in its magnitude would need to be quantified (we have not done it yet but showed what it needed to be), and it would have to be demonstrated that either (i) changes in the magnitude of known forcing agents in the model systems are systematically over-estimated by almost exactly the same amount or (ii) the radiative responses in the model systems are systematically underestimated by almost exactly the same amount. (Perhaps the word "exactly" should not be used in this context). However, testing either of these two hypotheses given the current model systems is not feasible until a candidate unknown forcing agent is identified and its magnitude is quantified.
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DSL at 13:36 PM on 26 May 2013Help close the consensus gap using social media
Actually, it does very much matter why. If we know why, then we know what to expect in general. We know the trend isn't going to go into long-term reverse -- not for a very long time.
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Dumb Scientist at 12:52 PM on 26 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
In my original post, I claimed that regressing global temperatures against the linearly-detrended Atlantic Multidecadal Oscillation (AMO) to determine anthropogenic global warming (AGW) assumes that AGW is linear. Thus, even if AGW actually were faster after 1950, Dr. Tung's method would conclude that AGW is linear anyway.
Dr. Tung dismissed Dikran Marsupial's MATLAB simulation because its conclusion is "obvious" and suggested coming up with a better example without technical problems. I disagree with this criticism and would like to again thank Dikran for his contribution, which inspired this open-source analysis written in the "R" programming language.
Can regressing against the linearly-detrended AMO detect nonlinear AGW?
Imagine that AGW is very nonlinear, such that the total human influence on surface temperatures (not the radiative forcing) is a 5th power polynomial from 1856-2011:
t = 1856:2011
human = (t-t[1])^5
human = 0.8*human/human[length(t)]Its value in 2011 is 0.8°C, to match Tung and Zhou 2013's claim that 0.8°C of AGW has occurred since 1910. The exponent of "5" was chosen such that the linear trend after 1979 is 0.17°C/decade, to match Foster and Rahmstorf 2011.
Tung and Zhou 2013 describes an AMO with an amplitude of 0.2°C and a period of 70 years which peaks around the year 2000:
nature = 0.2*cos(2*pi*(t-2000)/70)
Global surface temperatures are caused by both, along with weather noise described by a gaussian with standard deviation 0.2°C for simplicity:
global = human + nature + rnorm(t,mean=0,sd=0.2)
N. Atlantic sea surface temperatures (SST) are a subset of global surface temperatures, with added regional noise with standard deviation 0.1°C:
n_atlantic = global + rnorm(t,mean=0,sd=0.1)
Compare these simulated time series to the actual time series. The AMO is linearly-detrended N. Atlantic SST:
n_atlantic_trend = lm(n_atlantic~t)
amo = n_atlantic - coef(summary(n_atlantic_trend))[2,1]*(t-t[1])
Regress global surface temperatures against this AMO index and the exact human influence, after subtracting means to insure that the intercept handles any non-zero bias:
human_p = human - mean(human)
amo_p = amo - mean(amo)
regression = lm(global~human_p+amo_p)Will Dr. Tung's method detect this nonlinear AGW? Here are the residuals:
Let's add the residuals back as Dr. Tung does, then calculate the trends after 1979 for the true and estimated human influences:
Note that the absolute values are meaningless. A Monte Carlo simulation of 1000 runs was performed, and the estimated human trends since 1979 are shown here:
Notice that even though we know that the true AGW trend after 1979 is 0.17°C/decade, Dr. Tung's method insists that it's about 0.07°C/decade. That's similar to the result in Tung and Zhou 2013, even though we know it's an underestimate here.
The linearity of the estimated human influence was measured by fitting linear and quadratic terms over 1856-2011 to the same 1000 runs. The same procedure applied to the true human influence yields a quadratic term of 5.965E-05°C/year^2.
Even though we know that the true quadratic term is 5.965E-05°C/year^2, the average quadratic term from Dr. Tung's method is less than half that. The true nonlinearity of this AGW term is 5th order, so this is a drastic understatement.
Conclusion: Tung and Zhou 2013 is indeed a circular argument. By subtracting the linearly-detrended AMO from global temperatures, their conclusion of nearly-linear AGW is guaranteed, which also underestimates AGW after ~1950.
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user6244 at 12:38 PM on 26 May 2013Help close the consensus gap using social media
My earlier post got deleted.
I am trying to point out why it doesnt really matter what is causing the climate to change.
Instead we need to focus on methods to turn it around if the dire predictions are correct.
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user6244 at 12:25 PM on 26 May 2013Renewable energy is too expensive
let me try again.
Alternative energy is expensive bottom line it doesnt matter what is or isnt accounted for in the price. When I whip out my wallet I dont care how the price got to where it is at. At this moment in time if i come to the counter for a box of solar or a box of fossil fuels especially natural gas at the moment the cost of gas is far cheaper , no way around it.
I would like to link to an article that does a better job of making the point Energy policy and Environment
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nealjking at 10:36 AM on 26 May 2013Skeptical Science Study Finds 97% Consensus on Human-Caused Global Warming in the Peer-Reviewed Literature
The point of the paper is that the state of the current scientific literature reflects an overwhelming working assumption by relevant scientists that AGW is real and happening; and that, unfortunately, the impression of most Americans (for example) is that the scientific community is in a state of conflict about the matter.
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Ken in Oz at 10:29 AM on 26 May 2013On the value of consensus in climate communication
Correction to para 3 of my comment above - "Whilst this effort to examine the consensus amongst scientists is important and valuable..."
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Ken in Oz at 09:44 AM on 26 May 2013On the value of consensus in climate communication
Good comments! Definitely worth drawing attention to the strength of agreement amongst scientists but it does sound like careful consideration of the language used is necessary, so better call it something other than a scientific consensus!
Is it of any value to put the 3% under the scope -or would that simply give them a platform in which the "stick to the facts and don't leave out the provisos" scientists will face opponents that have impose no such restrictions or boundaries on their rhetoric? Against the experienced debater, who can argue as effectively that black is white and that 2+2=5 as argue the contrary, we need experienced debaters who can enter the fray, boots and all.
Whilst this effort to examine the consensus amongst scientists, I think what I would like to see is more effort along a different tack - a greater focus on our peak science bodies and on the role they have played in providing independent expert assessment of climate science, it's methodology and results.I'd like to see a starting from scratch rerun of that process, but with as much televised fanfare as possible - a look at the Royal Societies and Nation Academies, what and who they are and what they do, who picks the panels/committees and on what basis, a look at the members of those panels - both to highlight their credentials and how they've distinguished themselves - and to humanise them. And to show that these are people who have no personal axe to grind, are above any kind of group think and who will not be swayed by anything but the evidence at hand.
Whilst that might be another way to persuade the public of climate science's bona fides, I think the most important audience has to be those who hold positions of public trust - our elected and appointed representatives. ie the ones who have been recipients of government commissioned scientific reports and advice but have been choosing to dismiss and ignore:-Whilst the public has some right to their own opinions, those representative do not. Even if it's populism without responsibility that puts them there, once they are, they do have a greater and wider responsibility - to the entire community, not just those who backed their election. For them to endanger our future by wilfully ignoring government commissioned expert advice is a betrayal of that wider trust and responsibility.
Too many of our office holders have been lending climate science denial an air of respectability it has not earned and for those interests who want to obstruct strong climate policy, that high level support from skilled and persuasive speakers in positions of influence is (IMO) a more powerful influence over the scope and the tone of the public debate; 97% won't persuade the public if that 97% can't persuade a clear majority of those who hold positions of trust and responsibility on the public's behalf. -
gws at 07:19 AM on 26 May 2013To frack or not to frack?
some answers and analyses appeared on Climate Central here.
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Dikran Marsupial at 03:53 AM on 26 May 2013The anthropogenic global warming rate: Is it steady for the last 100 years? Part 2.
Prof. Tung wrote:
The observation now appears to be below the 95% variability bar of the CMIP3 model projections made in 2000
I have already presented an analysis showing that this statement is simply incorrect.
Do you stand by this statement, yes or no? If yes, please explain the error in the analysis.
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