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Steve Metzler at 09:32 AM on 7 May 2013Roy Spencer's Catholic Online Climate Myths
I'm with composer99 and others on this. Whenever Spencer's name comes up in a positive light in a climate science related thread, inevitably flung out there by a contrarian, I now throw the Cornwall Alliance book right back at them. It's nearly always *crickets* after that.
The poor man must carry a boatload of cognitive dissonance around with him. -
dana1981 at 09:21 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
John Chapman @5 - do you have a link to that Archibald prediction?
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barry1487 at 09:01 AM on 7 May 2013Participate in a survey measuring consensus in climate research
From the article that dealt with crowd funding of this project;
Over the past year volunteers here at Skeptical Science have been quietly engaged in a landmark citizen science project. We have completed the most comprehensive analysis of peer-reviewed climate science papers ever done. Some 21 years worth of climate papers – more than 12,000 in all – have been carefully ranked by their level of endorsement of human-caused global warming. We also invited thousands of the authors of these papers to rate their own papers.
https://skepticalscience.com/Be-part-of-landmark-citizen-science-paper-on-consensus.html
Seemed pretty clear to me that many papers had been rated by the authors of those papers.
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Jonas at 06:39 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
So SOI has no trend, but temperature has.
But even if SOI had a trend, this would not disprove human induced global warming: SOI could potentially be altered or given a trend by human made global warming (or even be disrupted completely by the human caused temperature change): a correlation does not explain which factor is the physical cause ...
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John Chapman at 06:39 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
David Archibald makes a similar prediction (catastrophic temp drop) for 2013 based on solar activity. We can visit that next year!
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chris at 03:58 AM on 7 May 2013Participate in a survey measuring consensus in climate research
Very interesting survey - well done for thinking this through - there's some fascinating elements of psychology and the nature of scientific understanding and knowledge in this.
Like most of the respondents on this thread I also slightly underscored relative to the authors consideration of their endorsement of AGW in their papers (I scored 3.0 on average; the authors scored 2.5 in my selection of 10).
I suspect this relates to two things. The first already mentioned here is that the authors have a conceptual framework outside of the specific element of the study in their paper and this influences their own perception of the level of endorsement in their study. The second is that an abstract doesn't give a full account of the level of endorsement that might pertain in the paper as a whole. The authors have access to this - those of us rating on the basis of abstracts alone don't.
In support of the above I had a look at a few of the papers in my ten in their entirety, after doing the survey. In all of the examples I looked at I would have scored the paper one step higher (ie.e. towards endorsement) had I known what was in the full paper.
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Steve L at 01:54 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
I know your philosophy is to tackle the science rather than the contexts that surround it, but a naive reader may get the impression from the beginning of the post that McLean is a legit climate researcher. His ridiculous prediction may say to a naive reader -- "I knew those climate science jerks didn't know anything about how climate works." But really that would be the wrong impression.
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JasonB at 01:43 AM on 7 May 2013Participate in a survey measuring consensus in climate research
MMM @ 31,
That's exactly what I meant by "just goes to show how deep the level of acceptance of the consensus is" above. It's much harder for the original authors to assess the abstract in isolation when they know what they feel and what they were trying to get across.
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JasonB at 01:39 AM on 7 May 2013Participate in a survey measuring consensus in climate research
Tom Curtis @ 30,
I did use the words "pretty remote" rather than "ridiculously remote" and "something to write home about", so I stand by my comment. :-)
Also, I didn't make the claim that the sample set were supposed to be from the entire set of 12,000, merely commented on the statements of those that did. It had already occurred to me that the original wording made no mention of the sample size for this exercise.
Finally, speaking of reading comprehension:
Finally, I am concerned that you have seen four sets given that we are asked to only take the survey once.
I never said I took the survey more than once. In fact I only took the survey exactly one time, the results of which I reported above. Since "results are only recorded if the survey is completed" it seemed harmless to check to see if I could reproduce the behaviour being reported on the fake skeptic blogs, and the last time was just so I could double-check the exact wording of the different categories.
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dana1981 at 01:11 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
dwr @1 - yes thanks, typo corrected. Indeed I haven't seen any contrarian blogs revisit McLean's prediction, other than the one mentioned in this post that rather absurdly tried to argue he was right.
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Michael2013 at 00:51 AM on 7 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
cargo transportation Thank you for a very interesting post!
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Philippe Chantreau at 00:48 AM on 7 May 2013Global Warming: Not Reversible, But Stoppable
Thanks for the precisions Tom.I confess that I could think of so many other things to do with my time that I did not go explore M.B.'s blog. I did not assume that he was an economist but he did have an overall tone not too distinct from the overly optimistic ones who advocate for a solve-all, laisser-faire market, in spite of clear evidence that it does not work. Your account about his blog seems to be consistent with his attempts at bribing people to go comment there...
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MMM at 00:05 AM on 7 May 2013Participate in a survey measuring consensus in climate research
Ah. Now I understand that "The average rating of the 10 papers by the authors of the papers was 2.7." is in fact worded correctly, since the random draws were not from the full 12,000+ but rather from the subset that had ratings by the lead author of the paper itself.
This might also explain why most people here are getting higher average ratings than the ratings given by the authors - the authors might be drawing on their full knowledge of the paper, while we have to depend on just what is contained within the abstract itself...
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dwr at 21:17 PM on 6 May 2013Distinguishing Between Short-Term Variability and Long-Term Trends
First paragraph below Fig 4. hyperlink 'McClean et al. (2013)' perhaps should be (2009)?
Funny how these failed predictions are seldom revisited by 'sceptic' blogs, isn't it.
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Tom Curtis at 20:04 PM on 6 May 2013Participate in a survey measuring consensus in climate research
JasonB @27, the probability that any one of the ten papers should be identical to any of the papers in a prior selection given that the papers are randomly selected from 12,000 papers is just 0.458%, or just under 1 in 200; which is fairly remote, but not ridiculously so. The probability that you would get an identical paper in two of four retries rises to 1.366%, or just under 1 in 73. Certainly nothing to write home about. The odds that one of 100 readers should have an identical paper to one reported by a previous reader rises to 36.782% (if they report all ten titles) and is hardly surprising at all. Hence I consider the evidence adduced that the paper selection is not random is decidely lacking, and consists mostly of a failure to differentiate between the odds of a certain result with a single trial, and that odds with multiple trials.
Having said that, the 12,000 papers are those surveyed in the original paper already accepted for publication. The specific claim is:
"This survey mirrors a paper, Quantifying the consensus on anthropogenic global warming in the scientific literature, to be published soon in Environmental Research Letters, that analysed over 12,000 climate papers published between 1991 to 2011."
So, claims of non-random sampling not only fail at mathematics, but also fail at reading comprehension.
As you surmise, it is likely that the abstacts used in the current survey in which you participated are a subset of the 12,000 used in the original paper. Specifically, they are probably drawn from those which actually recieved an author rating.
Speaking of which, it is my understanding that the author rating of a paper consists of the rating given to the paper by the lead author of the paper, rather than being the mean rating of all authors of the paper.
Finally, I am concerned that you have seen four sets given that we are asked to only take the survey once.
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jyyh at 18:28 PM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
<John Brookes> I think he said a few months back he's preparing a new book, so this may be related to that, real life hurries, that is.
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John Brookes at 17:39 PM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
Just one more very OT thing. What is up with Tamino? No new blog posts for some time, and not taking comments...
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jyyh at 16:53 PM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
oops, the equatorial argument might be wrong since it's projected that the high northern oceans would warm up the most relatively, thus the expansion of water would be higher in the northern hemisphere. but anyway the simple amount of ice melt = amount of sea level rise equation does not hold locally everywhere.
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Lanfear at 16:48 PM on 6 May 2013Participate in a survey measuring consensus in climate research
"anyway a nice way to educate people of the research done"
Aha!
So this is nothing but an insidious plot by the warmistas to force the true sceptics to read the propaganda created by the industrial climate complex.
In other words, nothing but a brute attempt to indoctrinate the opponents.
</troll>
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jyyh at 16:14 PM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
<pikaia> also considering the rotation of the earth, and the melt in the Antarctica, the highest rise should be equatorial so this estimate might not be too far off. (local housing infotainment) The lowest building limit currently for temporary residence buildings is (if I recall correctly) +2 m so there'll be a lot of ocean front cottages on sale in Finland in 2150, I guess. Currently their prices are way outside normal salary rates. Main reason of selling those to outsiders currently is testament disputes. In cities though, even residential buildings may sometimes be built this low. These might be pretty cheap after some heavy winter storm/harsh winter+fast spring (ending local infotainment)
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JasonB at 15:07 PM on 6 May 2013Participate in a survey measuring consensus in climate research
I saw this in the comments at Lucia's:
For whats its worth, my scores have been under 4, but over 3. That would mean the literature I reviewed, was lukewarm.
What it means is that, on average, the papers he reviewed were somewhere between "not mentioning what's causing global warming" and "implying humans are causing global warming".
Somehow this got converted, in his mind, into a statement about climate sensitivity.
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JasonB at 14:45 PM on 6 May 2013Participate in a survey measuring consensus in climate research
On a side note, I had a look at WUWT's posting on this mentioned above and I had to laugh — the conspiracist ideation runs deep. :-) Their mantra appears to be "I may be paranoid, but am I paranoid enough?" :-) I love the fact that they're unwilling to have a go because of what it may reveal about them.
The concerns centre around two aspects; the first is the survey code embedded in the URL, which is presumably intended to track which site the reviewer followed the link from. To avoid triggering a Pavlovian response next time (assuming conspiracy theories weren't the intended purpose of the survey code :) I would suggest using the HTTP referer field instead next time. It isn't perfect (copying-and-pasting the link instead of clicking on it will defeat it) but it might filter out some of the noise.
The second is the randomness of the papers. I did a quick calculation and the chance of two people seeing the same paper out of a random selection of 10 out of 12,000 is pretty remote, so the fact that I've seen the same paper twice in four sessions suggests that the actual number of papers being used is far fewer than 12,000. This makes sense if the authors of the papers were actually asked to rate their own papers, and it wouldn't take many papers to turn up useful results.
The funny thing is that when I noticed the above it made me laugh and very keen to see what the outcome will be; when the WUWT crowd noticed it they got too scared to take the survey. It's like primitive tribes-people being afraid of their soul being captured by someone taking a photograph. Brilliant!
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JasonB at 14:27 PM on 6 May 2013Participate in a survey measuring consensus in climate research
barry,
It's not clear whether "the paper authors' ratings" refers to Cook et al or the authors of the original papers themselves. See MMM @ 18 above. The way it's worded is certainly ambiguous and assuming MMM is correct I agree that it could do with rewording. If the ratings really are from the authors of the original papers then the fact that an unbiased reading of their abstracts in isolation by third parties consistently seems to give a lower level of endorsement of the consensus than the authors themselves just goes to show how deep the level of acceptance of the consensus is.
I've long been impressed by the lack of bias amongst SkS' readership, and a willingness to disagree with each other even if it gives "ammunition" to "the other side".
As for the difference in scores, the biggest problem is likely the implicit endorsement question, which is highly subjective: "abstract implies humans are causing global warming. E.g., research assumes greenhouse gases cause warming without explicitly stating humans are the cause." The papers I classified as "neutral" rather than "implicit endorsement" all took global warming for granted, but none of them mentioned the cause of that global warming — rather, they were talking about the effect of that global warming on the particular subject of the paper. As I mentioned above, reading just the first line of the introduction to one of those papers made it very clear that the authors of the paper themselves fully supported human causation, but because they didn't say that in the abstract I had to classify that as neutral under my interpretation of the rules. It is possible that others, looking at the same abstract, might say that the paper implicitly endorsed human causation of global warming because, for example, it didn't try to suggest any other cause or cast doubt on the prevailing theory. Simply changing my four "neutral"s to "implicit endorement"s on that basis would reduce the difference to 2.9 (me) vs 2.8 (the authors).
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chriskoz at 14:20 PM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
John Brookes@4,
You are correct. "uneven warming of seas" should be replaced by "isostatic rebound from last glacial maximum". This and "changes in the Earth’s gravity field" are the 2 mean SL variations we know. Of course we are considering long term, excluding short term noise such as tides and weather fluctuations. "Uneven warming" is part of the weather.
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barry1487 at 13:13 PM on 6 May 2013Participate in a survey measuring consensus in climate research
I may not be a complete dunce.
Of the 10 papers that you rated, your average rating was 3.5 (to put that number into context, 1 represents endorsement of AGW, 7 represents rejection of AGW and 4 represents no position). The average rating of the 10 papers by the authors of the papers was 3.3.
Everyone posting here so far has rated their 10 papers less favourably towards endorsing AGW than did the authors, indicating a distinct lack of bias for this blog's readership. It may be that the abstracts are more neutral than the full results of the paper. Nevertheless, this small sample suggests an honest, objective approach from SkS readers, not to mention the comments above. Here be true skeptics.
If it's not giving away too much before submission/publication, how did the Cook et al team's results match up with the paper authors' ratings?Response:[JC] Nah, that's giving too much away, Barry. You're just going to have to wait :-)
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John Brookes at 11:33 AM on 6 May 2013Climate change will raise the sea level in the Gulf of Finland
"There is, however, great regional variation in the rise, for reasons such as the uneven warming of seas,..."
I would have thought that uneven warming would not effect the regional sea level?
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macoles at 09:01 AM on 6 May 2013WMO Annual Climate Statement Confirms 2012 as Among Top Ten Warmest Years
Thanks LarryM, that link clears it up nicely. I also hadn't realised that these ENSO indices can vary significantly month to month rather than just year to year, so the starting month makes a big difference too.
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Tom Curtis at 08:01 AM on 6 May 2013Participate in a survey measuring consensus in climate research
I should add, Shub also demonstrates the much larger readership at the "skeptical blogs" than at the pro-science blogs. It follows that had the owners of those "skeptical" blogs posted links to the survey, the proportion of "skeptics" to pro-consensus respondents to the survey would have been reversed. The lack of "skeptical" respondents to the survey was not by design of Lewandowsky and his co-authors. Rather it is the direct consequence of "skeptics" not wanting their views of their supporters to be known. Probably with good reason.
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Tom Curtis at 07:46 AM on 6 May 2013Participate in a survey measuring consensus in climate research
keitho @22, its odd that you should refer to Shub Niggurath's piece as proof of chicanery in LOG13 (moon landing paper). What he demonstrates after detailed (and likely biased) analysis is that slightly less than 80% of commenters on the pro-science sites that posted LOG13 survey support the consensus on climate change; ie, approximately the same percentage as in the survey itself. Beyond that the analysis seems entirely based on misinterpreting "broad readership" as meaning "readership equally divided between those opposing and those accepting the consensus".
Curiously, despite his detailed analysis, he fails to mention that a link to the survey was posted on at least one "skeptical" blog, ie, Junk Science. Admitedly Junk Science was not one of the blogs contacted by Lewandowsky, but that is hardly relevant. The fact that the link was posted on a "skeptical blog" undermines the entire basis of Shub's analysis.
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Tom Curtis at 07:35 AM on 6 May 2013Global Warming: Not Reversible, But Stoppable
Philippe Chantreau @93, I would not assume that Bahner is an economist, or indeed, that he has any university level economics training. His blog shows only 12 posts since it started in July 2007, none of which shows detailed economic reasoning, or detailed reasoning of any sort. The only thing it really shows is that he likes reading cornucopian futurists, and that he is almost completely ignorant of physics (he claims that what amounts to a 20 foot wide barrier of weighted corks could stop a storm surge, and that the weighing would stop it drifting of station in the face of a hurricane). HIs blog ("Random Thoughts") is well named, but could perhaps be better named "Thoughtless comments".
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Philippe Chantreau at 03:20 AM on 6 May 2013Global Warming: Not Reversible, But Stoppable
Mark Bahner sounds like an economist. Only they can postulate the future existence of wealth and then start using it as if it not only will come into existence for sure, but in fact already exists. That attitude, when it turns into a frenzy, was the cause of the largest market crashes in history. A sizeable amount of wealth in today's world is wealth that does not have any real existence. Of course, the really clever ones are those who can cash in on thesefrenzies on the very short term, because they keep the assets acquired even after the whole house of cards collapses.
I tend to trust economists that were able to predict bubbles and crashes before they happen, such as Jeremy Grantham. Unfortunately, that kind of clearsighted economist is unlikely to gather more attention about this subject than they did with the Japanese bubble, tech bubble, housing bubble, etc. People like easy and worry-free, so the Bahners of the World will always have a larger audience. Then when it hits the fan, the clearsighted ones will be under fire for not being more convincing.
http://www3.imperial.ac.uk/climatechange
http://www2.lse.ac.uk/GranthamInstitute/Home.aspx
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keitho at 01:13 AM on 6 May 2013Participate in a survey measuring consensus in climate research
I do hope that the same chicanery that happened with the last attempt at profiling doesn't happen again. Shub Niggurath has done some analysis on that paper and it doesn't look good . .
http://wattsupwiththat.com/2013/05/05/lewandowsky-et-al-2013-surveying-peter-to-report-on-paul/#comment-1297865
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LarryM at 00:48 AM on 6 May 2013WMO Annual Climate Statement Confirms 2012 as Among Top Ten Warmest Years
macoles - There are several ways to define El Nino/La Nina/Neutral, so no exact definition. The WMO press release didn't specify their definition, but for the above animated graph see the associated caption and links by clicking on it, or go directly to the explanation in this article. In summary, the average of 3 common ENSO indices was calculated for each year, and the bottom, middle, and top one-thirds were used as the 3 categories.
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pikaia at 18:02 PM on 5 May 2013Climate change will raise the sea level in the Gulf of Finland
It is an interesting fact that if the whole of the Greenland ice sheet melted, while average sea levels would rise by 7 metres, near Greenland the sea level would FALL by 100 metres! This is because the ice exerets a considerable gravitational force on the surrounding ocean.
http://www.youtube.com/watch?v=RhdY-ZezK7w
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Rob Painting at 16:44 PM on 5 May 2013Climate change will raise the sea level in the Gulf of Finland
Why would you find a rising sea level trend there surprising? The region was squished down by the presence of the Fennoscandian ice sheet during the last ice age, and the land has been rising back up since then. The rate of glacial isostatic uplift slows over time, so a globally coherent melt of land-based ice (and consequent global sea level rise), such as today, will eventually overcome local factors.
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JasonB at 16:38 PM on 5 May 2013Global Warming: Not Reversible, But Stoppable
Mark Bahner,
Of course not. I consider it profoundly immoral for the poor to sacrifice for the benefit of the rich and well-off. Don't you, too?
I consider it a meaningless slogan without context. With context, what you are saying is that not only should poor people throw their rubbish on the front lawns of the rich because the cost of cleaning it up as a proportion of income is less for the rich people than the cost of garbage collection is for the poor, but that it's actually "profoundly immoral" to ask the poor people to take care of their own garbage.
Where this analogy breaks down, of course, is that in the actual case in question you don't actually know for a fact that the recipients of the rubbish are rich. There are plenty of reasons to suggest they may actually be worse off than we are, economists' fantasies notwithstanding. Firstly, they will be dealing with the consequences of AGW, which we've barely had a taste of so far. Secondly, they won't be able to take advantage of the huge boon in cheap energy that we've benefited from over the past 150 years or so thanks to fossil fuels, which has had an enormous effect on our standard of living, because they are a finite resource anyway.
And even if GDP increases, that doesn't mean that everyone benefits. Those living on low-lying Pacific islands and places like Bangladesh may find their homelands and way of life destroyed forever. Those depending on sea-sourced protein may be suffering profoundly from the consequences of overfishing and the effect of ocean acidification on the food chain. What about those dependent on glacial run-off for their water supply? Surely it is profoundly immoral for them to have to sacrifice for the benefit of those of us now enjoying the benefits of the fossil fuel boom? It does seem a little self-serving to suggest that it would be immoral of us to lower our living standards for their benefit by making it seem as if they are the rich ones and we are the poor.
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Matt Fitzpatrick at 16:17 PM on 5 May 2013Climate change will raise the sea level in the Gulf of Finland
If the Gulf of Bothnia starts showing a rising trend too, that'd be a pretty big surprise.
English Wikipedia's article on the Baltic Sea has some interesting background on this topic, including a map showing about how much of Finland was submerged 11,000 years ago.
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Composer99 at 14:01 PM on 5 May 2013Roy Spencer's Catholic Online Climate Myths
Phil L:
I don't really see the Cornwall Alliance as being a matter of reflecting badly on evangelical Christians - at least not in the context of Dr Spencer.
Rather, what I perceive is the case is that it reflects badly - very badly - on Dr Spencer.
Basically, as far as I can see, as long as you have your scientific integrity intact, you can be corrupt, perjured, flawed, fallible, whatever - and still function effectively as a scientist.
But if you compromise your scientific integrity, it doesn't matter how upstanding you are in every other area of your life - it's game over, as far as being taken seriously as a scientist goes.
IMO Spencer signing on to the Cornwall Alliance means he has sacrificed his scientific integrity. Stick a fork in him: he's done.
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scaddenp at 11:48 AM on 5 May 2013Roy Spencer's Catholic Online Climate Myths
Good point Phil L,. And check this by Professor of Public Policy, J Boston here
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michael sweet at 10:55 AM on 5 May 2013Renewables can't provide baseload power
ThinkProgress has an article about Portugal generating 70% of their power for the first quarter of this year from renewables. They had about 37% from hydro and 27% from wind. Solar was only 0.7%. (I am not sure why the numbers do not add up to 70%. The original Portugese press release contains these numbers). Since hydro is the most flexible method of power generation (more flexible than coal, gas or nuclear), being able to ramp up quickly if needed and available at any time, they are able to easily use a lot of wind. Apparently it was rainy and windy so they got a lot more renewable than last year. They saved a lot of cash not buying coal and gas. For those who say renewables cannot provide more than 40% of energy, what do you think about this proof of concept? They exported about 6% of energy used. Presumably they exported on windy days. Stilll nowhere near as much export as the nuclear plants in France have to do every night.
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macoles at 10:53 AM on 5 May 2013WMO Annual Climate Statement Confirms 2012 as Among Top Ten Warmest Years
LarryM @2
Why do we have a difference in the year categorisations between these two graphs?
Isn't there some definitive way to determine what year is El Nino / La Nina / Neutral?
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John Hartz at 10:17 AM on 5 May 2013Global Warming: Not Reversible, But Stoppable
@Mark Bahner #87:
You stated, "I consider it profoundly immoral for the poor to sacrifice for the benefit of the rich and well-off."
The findings presented in the article, U.N. Finds “Little Appreciation” for Human Rights among U.S. Businesses" suggests that many U.S. business are acting immorally.
Do you agree?
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Tom Curtis at 10:16 AM on 5 May 2013Global Warming: Not Reversible, But Stoppable
1) Given Mark Bahner's stated moral outrage about the poor being asked to sacrifice for the benefit of the rich. Given that, no doubt we can expect him to clearly state a desire that the US government should ignore the deficit, which afterall, will be payed of far more easilly by future, wealthier generations (given his assumptions).
2) I have been checking two scenarios to see if their is any merit in Bahner's approach.
In both scenarios, CO2 emissions grow at an initial rate of 2% per annum (compared to the average over the last decade of 2.7% per annum). That rate reduces such that the emissions in any given year (y) are:
Emissions(y-1)*(1.02-(1.0234^(y-2013))/100)
The constraints on emissions growth are expected to come from increasing cost of fossil fuels and increasingly competitive renewable energy. The total curve represents the combustion of approximately twice current proven economic reserves. For comparison, Bahner assumes peak emissions at 30% above current emissions in thirty years, followed by a rapid fall of. This scenario shows a peak of 17.5% above current emissions in thirty years, followed by a rapid fall of, and so is optimistic on his assumptions. I also believe it to be optimistic on a BAU approach, but not entirely implausible.
In both scenarios, 1% of GWP is spent on carbon sequestration annually from 2014 until CO2 levels decline to 330 ppmv, at which level they are then maintained. The cost of carbon sequestration is set at an initial value of $1000/tonne and falls by 1% per annum, falling to less than $420 a tonne by 2100.
Growth in Gross World Product (GWP) in purchasing power parity (PPP) terms is assumed to be 4.5% per annum in the first, optimistic, scenario. That is greater than the average over the last 40 years (see graph @60 above), a period which has seen a slight but persistent decline in GWP despite the advent of the information technology revolution. Given the costs of ongoing global warming, not to mention the 1% of GWP spent on carbon sequestration every year, I think this assume growth is (very) optimistic.
In the alternative scenario, growth in GWP starts at 4.5% per annum, but the growth rate increases by 0.1% per annum. That acceleration of the growth rate means GWP by a factor of more than 2000 by 2100, or given standard estimates of population growth, in represents an increase in PPP GWP/capita by about 1000 by 2100. I therefore think it reasonably represents Bahner's (franky fanciful) assumptions.
Temperature response is set to track the Transient Climate Response to CO2 concentrations. This over estimates temperatures in the early stages of the scenarios (because it ignores sulfates) but will be approximately correct in later stages.
The results of the two scenarios are virtually indistinguishable from each other (and the no sequestration case) for the first 25 years (2014-2038) of the scenarios, with temperature climbing rapidly to more than 2 C above pre-industrial levels by 2035. They remain at elevated levels (> 2 C) for 57 years in the optimistic scenario and 33 years in the Bahner scenario. This is the key problem with Bahner's approach (even if we ignore his absurdly optimistic assumptions). Assuming PPP GWP growth of 4.5% per annum (let alone the approx 7% per annum in the Bahner scenario) in a plus 2 C world is absurd. If in fact, and very improbably, such high levels of growth can be maintained in a 2 C world, then, indeed, in strictly economic terms AGW is no problem. That, however, needs to be established - not used as a hidden assumption. If, as is more likely, growth in a plus 2 C world falls towards zero, or even becomes negative; sequestration will remain limited in its ability to draw down atmospheric CO2 and CO2 concentration will track closely the no sequestration pathway (ie, rising above 1000 ppmv and heading for a plus 5 C world).
So, at best, Bahner's solution to AGW works if, and only if, AGW is not a problem to begin with. If it is a problem, ie, if plus 2 C worlds will have negative impacts on the world economy, mitigation to avoid such scenarios is by far the better investment, although sequestration may become a viable alternative in the mid to later twenty-first century. Even then, sequestration will only be a viable strategy in the later twentieth century if we have significantly mitigated CO2 emissions in the first half of the twentieth century.
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Phil L at 03:10 AM on 5 May 2013Roy Spencer's Catholic Online Climate Myths
Please don't judge all evangelicals by those like Roy Spencer who signed the Cornwall Alliance. Check out the Evangelical Climate Initiative (ECI), which accepts climate science, takes the threat of climate change seriously, and calls on evangelical Christians to address the issue.
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Rob Honeycutt at 02:35 AM on 5 May 2013Global Warming: Not Reversible, But Stoppable
Mark said, "Of course not. I consider it profoundly immoral for the poor to sacrifice for the benefit of the rich and well-off. Don't you, too?"
Of course, everyone believes that. Tax structures do not inherently overburden the poor, if they're structured correctly. In fact, they generally benefit the poor and middle class.
It's one reason I'm more inclined to support a tax and dividend system.
But, JasonB has an important point that you casually dismissed. If the cost of removing CO2 from the atmosphere is $500 then that is the true cost of emissions. And that is the point I've been trying to address.
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grindupBaker at 18:29 PM on 4 May 2013Guemas et al. Attribute Slowed Surface Warming to the Oceans
I figured 14.49 ZettaJoules p.a. heating based on 0.9 wm**-2 I heard in a Dr. Trenberth lecture. I figured 1,600 years to warm ocean example +2.8 degrees @ that rate. I was about to theorize if surface stablizes in 100 years or so @ +2.8 degrees (because TOA radiation balances there) then oceans will continue warming 1,500 years more until it's all +2.8 degrees but that's not what will happen because 0.9 wm**-2 would be reducing to zero. Oceans will warm indefinitely until something reduces the +2.8 degrees surface temperature but warming will be on a curve of reducing rate until it's inconsequential. Needs some working out.
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Isaac at 17:26 PM on 4 May 2013Climate's changed before
"The combined evidence indicates that the net feedback to radiative forcing is significantly positive."
I would say that the fact that the planet survived several cycles of glaciation over the last half a million years, and that the planet's sensitivity can be computed, is an indication that the net feedback is negative. Positive feedback would cause a runaway temperature, even after the forcing function is removed (See amplifier squeaks.)
However I would like to verify the list of the various feedback mechanisms.
I read a lot about poitive feedback processes. Water vapor, atmospheric CO2, polar ice reflection, and maybe more. As for the negative feedback I saw only brief mention of clouds and black body radiation.
Are there any other negative feedbac mechanisms?
What is the dominant negatve feedback mechanism?
Is there evidence of its occurence at the peak of the glacial warming cycles?
Moderator Response:(Rob P) Please see this SkS post by Neal King:Why positive feedback doesn't necessarily lead to runaway warming. Further comments on positive feedback should be directed there - where it is considered to be on-topic.
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Rob Painting at 16:44 PM on 4 May 2013Guemas et al. Attribute Slowed Surface Warming to the Oceans
GrindupBaker - the reference is in regard to the idea that heat buried into the deep ocean will resurface during the next El Nino-dominant phase. That isn't correct, only heat in the upper ocean is involved with the ENSO-related ocean-to-atmosphere heat exchange.
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sidd at 16:41 PM on 4 May 2013Global Warming: Not Reversible, But Stoppable
I think it is profoundly immoral to put off cleanup to future generation. What if
1)problem is worse than we think ... and every projection is coming in worse
2)what if they got other, unforeseen by us, problems
3)most bad, what right do we have to make the silent unborn clean up our mess ?
they cannot defend themselves. This attitude is, to put it baldly, "Grandkid is worth nuttn because of the discount rate."
Applying an intergenerational discount rate between generations is evil. I suppose that's an unfashionable Rawlsian, (or, gasp, even Georgist!) thing to say.
People who rely on others to pick up after themselves are leeches. Leeches on unborn "... have a special dung heap in the low rent section of hell..." with their name on it.
[ I am indebted to Hunter S. Thompson for that last quote ]
sidd
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grindupBaker at 14:59 PM on 4 May 2013Guemas et al. Attribute Slowed Surface Warming to the Oceans
Rob Painting @14 I disagree with "the warming of the deep ocean will not affect global surface temperatures for hundreds of years" because deep ocean will start warming somewhat sooner than hundreds and it affects global surface temperatures as soon as it starts warming, by cooling the surface. You all have it conceptually backwards - the surface is valiently attempting to stop "global warming" by raising its temperature enough so it can match the incoming at TOA but the dratted ocean will keep draining its heat and keep the "global warming" going for a Boon's Age (unless, of course, the excess CO2 gets taken up).
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