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Doug Bostrom at 18:00 PM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Further to PluviAL, in the past half-dozen years China has equipped homes with 20GWE+ of domestic solar hot water, the equivalent of 10 of the largest nuclear plants crisply instantiated as facts on the ground. Here in the US we pretty much ignore this ridiculously easy to obtain energy, apparently preferring instead to dream and talk about a resurgence of nuclear power when fraction of the money required to realize our romance with atom splitting could actually solve problems for us immediately. Not to say we shouldn't split atoms, just that we frequently let imaginary perfection be the enemy of factual good enough.
Indeed, China doesn't "just talk about it."
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KR at 16:08 PM on 6 March 2013Reality Drop - using social media to rapidly respond to climate misinformation
As a not unexpected note, WUWT has blocked links from Reality Drop, insofar as they can, using the URL origin.
Apparently WUWT's best response to critiques based on peer-reviewed literature is to stick their fingers in their ears, sing "la la la", and ignore them. That's just sad.
Disengaging from discussion, ignoring other points of view, blocking dissention - I seem to recall complaints from the 'skeptics' on just those items. "Emulating the Enemy", or at least the perception of the enemy, perhaps?
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PluviAL at 15:57 PM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Habilus: I have been to China extensively. In less than 6 years they built the largest High-Speed rail road network in the world. When China sets out to do something they do it, they don't just talk about it. Your comment makes me think the rest of your comments are just as pooly based. That the air is dirty is not a question, so it is a straw man argument on your part. Do you work for the pollution company interests?
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Bob Loblaw at 14:42 PM on 6 March 2013Temp record is unreliable
..and furthermore...
Air temperature measurements were not started with the monitoring of climate in mind. The concept of "climate" probably didn't even exist in those terms until after people started accumulating data. As experience accumulated, methods of measuring temperature improved (and changes need to be accounted for in looking at long-term trends).
Even though historical air temperature records are an incomplete view of historical global conditions, they are useful. Extensive land surface air temperature records go back much further than ocean temperature records. We understand many of the linkages between ocean and land temperatures, and we can account for much of the differences in patterns. AIr temperatures are but one part of the jigsaw puzzle, but they do help.
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scaddenp at 14:13 PM on 6 March 2013Temp record is unreliable
Further to DSL
2- no it is absolutely not a simple average. First "global average temperature" is tough to define (and measure) so what is usually calculated is global average anomaly. Second, all the temperature records use area weighting. However, there is a lot of differences in the detail (and a lot of detail). The advanced section of this article gives you good pointers for more information.
3- Any proxy of use has to have two attributes - a way to tell the time accurately and a way to tell the temperature. The best long term proxy is ice core bubbles. The "lock in" time for a bubble is short and where you have annual snow layers, you have very good clock. Thermometry is also very good compared to most other proxies. Resolution degrades as you go back in time for all proxies. Ice core gets you 600Ka but only for very selected places on earth (greenland and Antarctica). Spelothems are prob next best as far as I know but more problematic for absolute dating and thermometry but wider global coverage. Going back beyond these you lose time resolution badly as you become dependent on radiometric dating resolution. Resolution will depend on the particular technique. In something like benthic forams from marine cores you can good relative time but not absolute time (and a lot of fun interpreting the thermometry).
In short all proxies have issues of one sort or another and paleoclimate studies are best within integrating multiple lines of evidence.Go to http://www.ncdc.noaa.gov/paleo/recons.html for data but read metadata about limitations before leaping to any wild conclusions.
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DSL at 13:41 PM on 6 March 2013Temp record is unreliable
grindupBaker,
1. Public interface. The thermal capacity of the oceans is difficult to explain to the general public, and surface temp is "in your face."
2. Hansen 2010; HadCRU; BEST
3. I'll defer to others.
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Phil L at 13:34 PM on 6 March 2013Reality Drop - using social media to rapidly respond to climate misinformation
brent @ 17, my apolgies for missing the tongue-in-cheek nature of your comment. I agree that Michael Mann's book is a masterpiece, and I'm a big fan of Mark Twain. My use of the term "your ideology" was unwarranted - I mistakenly thought you were dismissing Spurgeon as a citation because of the fact that he was a Baptist preacher, not because of his current obscurity. To me it's a simple question of who said it first, no matter how famous or obscure that person was.
"People misquote me on the Internet all the time. Please cut that sh1t out" -Albert Einstein
But I realize this discussion has strayed off topic .... Reality Drop looks like a useful tool with potential to complement SkS's carefully researched articles.
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jyyh at 13:32 PM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
What Tom Curtis said: Seconded. While it's good to debunk denialist articles individually too, the continous stream of crap, illogical presentations and outright lies by the usual suspects may effect also good sites. Luckily, the article refuting Goddard etc. types usually contain their name on the headline so I can skip the article. I mean, I have decided their originals (and comments therein) aren't worth the bandwith, but still someone might still believe then so the debunkings should continue, however frustrating it is. I'd like to call it 'The propaganda-machine of deniers', but I'm still not certain, they might just be assholes having fun at the expense of future generations. (oops, off topic, please delete.)
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grindupBaker at 13:30 PM on 6 March 2013Temp record is unreliable
I have 3 questions (1) Since oceans store same heat per ~20' depth as all air & all land that's relevant (to ~20' depth) why is avg global temp being used rather than ocean heat energy in the graphs publicly discussed ? (2) Is avg global temp a simple avg of all readings, or weighted ? (3) Can I find a proxy historical global temp set (600Ka ? 600Ma ?) to fine time resolution - a millenium ? a century ?). Anybody ?
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Philippe Chantreau at 12:13 PM on 6 March 2013Why SkS withdrew from the Bloggies
Nice Kr :-) Nothing like real data analysis, something that Watts took years to do and when he did he couldn't acknowledge the results. Not surprising since the results invalidated the very initial premise of his site's existence. Nuff said
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KR at 11:54 AM on 6 March 2013Why SkS withdrew from the Bloggies
Doug Bostrom - Less than 1:20 rated as good. Hmm, that seems to indicate a 2-sigma significance result, that "good" is not supported by the evidence for that blog source.
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Riduna at 11:42 AM on 6 March 2013‘Frozen Dirt’ and Methane … ‘We Cannot Go There’
The essay ignores the elephant in the room – methane trapped in clathrate and as gas in surrounding sediments beneath permafrost covering the seabed of the Siberian Continental Shelf. This has been quantified by Shakhova and Semiletov as comprising not less than 1,700 gigatonnes. As a result of seabed permafrost degradation methane has been observed venting to the atmosphere. Because of the shallow depth of water covering the continental shelf, it has no time to oxidize to far less potent CO2.
Continuing loss of sea ice and Arctic Ocean warming, combined with atmospheric warming is likely to result in accelerated loss of seabed permafrost, increasing venting of methane to the atmosphere. This has the potential to reduce sub-seabed pressure, destabilise shallow clathrates, rapidly increasing methane excursions from them to the atmosphere, further amplifying Arctic temperatures and chnaging global climate.
Daniel Bailey rightly observes that “the Kraken does not yet wake... “ But it is already stirring and nothing short of reversing Arctic warming is likely to prevent it (methane) from venting to the atmosphere in such volume as to bring about rapid and permanent climate change before 2100.
Do I hear mutterings about geo-engineering – spraying sulphides at the top of the stratosphere - to prevent this? The clothing industry could produce a whole new range that can withstand acid rain and we could all get on with business as usual.
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Tom Curtis at 11:16 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
First, I want to commend Rob Painting on an excellent article. I particularly appreciated the clear statement of the basis for the conclusions, along with the relevant caveats. Could a link to this article be placed at the bottom of the various sea level myth rebutals so that it is not lost in the continuous stream of posts at SkS, and left to languish in obscurity.
In particular, a link would be appropriate on these pages:
How much is sea level rising; and
Why Greenland's ice loss matters.
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Tom Curtis at 11:09 AM on 6 March 2013Why SkS withdrew from the Bloggies
1) Eclectikus makes a variety of claims about Richard Feynman's views on pseudo-science, but does not quote a source for those claims. Google searching, I have found two discussions of pseudoscience by Feynman available on the net. The first, and more substantive, only refers to pseudoscience in the introductory comment which was not part of the actual lecture. In the lecture itself, he only refers to "cargo cult science", a term which is definitely pejorative. Clearly Feynman considers "cargo cult science" and "pseudoscience" to be the same thing.
The distinction between cargo cult science and real science turns out to be a kind of scientific integrity. Feynman describes it as follows:
"... It is interesting, therefore, to bring [the distinction between cargo cult science and real science] out now and speak of it explicitly. It's a kind of scientific integrity, a principle of scientific thought that corresponds to a kind of utter honesty--a kind of leaning over backwards. For example, if you're doing an experiment, you should report everything that you think might make it invalid--not only what you think is right about it: other causes that could possibly explain your results; and things you thought of that you've eliminated by some other experiment, and how they worked--to make sure the other fellow can tell they have been eliminated.
Details that could throw doubt on your interpretation must be given, if you know them. You must do the best you can--if you know anything at all wrong, or possibly wrong--to explain it. If you make a theory, for example, and advertise it, or put it out, then you must also put down all the facts that disagree with it, as well as those that agree with it. There is also a more subtle problem. When you have put a lot of ideas together to make an elaborate theory, you want to make sure, when explaining what it fits, that those things it fits are not just the things that gave you the idea for the theory; but that the finished theory makes something else come out right, in addition.
In summary, the idea is to give all of the information to help others to judge the value of your contribution; not just the information that leads to judgement in one particular direction or another."
(Quoted from here.)
Let's be very direct about this. A cherry picker does not "... give all of the information to help others to judge the value of your contribution". Somebody who does not calculate the predictions of their theory does not "... give all of the information to help others to judge the value of your contribution". Somebody whose account of the science contradicts itself does not "... give all of the information to help others to judge the value of your contribution".
Therefore, by Feynman's definition there is no doubt that the Coleman article is "cargo cult science", ie, pseudoscience.
Eclecticus can disagree with that assessment if he likes, but he cannot honestly do so while quoting Feynman as his authority. If he disagrees, he owes us his own definition of "pseudoscience", and he needs to justify it with rational argument - something he appears unprepared to do.
It should be noted that one person falling below this ideal does not make a discipline pseudoscience. Science is a self correcting communal activity. Individual scientists are human, and like most humans tend to protect favoured theories from criticism to some extent. But the scientific community as a whole, particularly the scientist's peers in the discipline will not be so slack. In this respect, climate science is clearly scientific; whereas the AGW "skeptical" movement is astonishingly reticent in criticizing even the most absurd ideas, provided they would make taking action against global warming, if true. The political effect of those theories clearly outways, in their minds, any commitment to scientific integrity. That, and perhaps, a fear that if they are too open in exposing the fallacies of their fellow travellors, their fellow travellors might return the favour.
2) It was well said by some ancient sage, and recorded in the Tanakh that,
That was said while books where still written by hand on parchment. You can imagine that sage's distress if confronted with the internet.
The point is that, even if we confine ourselves to scientific papers (for example), there is far more material produced than any one person could hope to read, let alone analyse and understand. To cope with modern flood of information, we need spam filters.
As noted, this applies even in science. That is the purpose of peer review, which is supposed to weed out papers that are obviously poorly supported or simply wrong. Peer review does not pretend, and cannot hope, to eliminate all errors from scientific papers. But it does aim to ensure that any errors that make it through to publication are either subtle, ie, not easy to find, or interesting, ie, to show that they are errors you need to learn something new.
A good science blog should also be a spam filter. It should weed out the pseudoscience, and the misleadingly presented. It should present only posts which are reasonable summaries of the science, which are interesting, and encourage people to learn critical thinking rather than gullibility.
By this standard Skeptical Science is a good science blog.
By this standard, WUWT is the antithesis of a good science blog. It does not weed out the bad articles, such as that by Coleman. It certainly does not encourage critical thinking, but instead teaches gullibility. The same can be said of all four remaining short listed nominees for the best science award at the blogees.
Regardless of what definition Eclectikus contrives to maintain his belief that WUWT is a good science blog, the fact remains that as a spam filter to filter out bad science and bad reasoning, WUWT fails abysmally. Indeed, it works more to filter out good science and good reasoning rather than the reverse.
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Doug Bostrom at 10:44 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus: 93.- doug_bostrom, some of them only support a reading diagonal, maybe, but "WUWT" is not specifically a divulgative blog like this, and this has to be in the reader's mind.
Twenty articles and not a single one you're prepared to unreservedly endorse as "good?" Having nothing more specific to work with I take it thereby that when you say "I've also read good articles at WUWT" you mean some proportion fewer than 1:20 are "good" by your own estimation.
Perhaps if I'd provided a larger sample (50?) we'd learn something more about the "good versus something else" ratio. As it stands, some proportion less than 1/20th useful is not an impressive record. But that's not necessarily the end of the story; it's still possible that you could identify which of the sample consisting of the last twenty climate science related articles at WUWT strike you as good.
Unfortunately even if 1:10 articles or even 1:5 articles at WUWT prove to be worthwhile we're still seeing confirmation of John Cook's original point of his blog post.
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Leto at 10:43 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus@106. The definition did not seem to come up in that video - unless I missed it. But it doesn't matter where the definition came from - the way you have applied the definition is invalid, even if the definition had some merit in another context, with the appropriate caveats in place.
It would be reasonable to characterise as "pseudoscience" a discipline that was unable to explain any empirical data or produce any empircal predicitons. On the other hand, it would be ludicrous to characterise a discipline as pseudoscience simply because it failed to explain all empirical data, or had a few unknowns, like physiology and climatology.
So, are you saying that climate science is pseudoscience in the same way that physiology is pseudoscience?
And, while we are on the topic, how would denialist climate theory stack up against the requirement that it must have explanatory and predictive power to be considered science? What empircal data is better explained by a denialist than by consensus climate science? Even cherry-picked snatches of noise do not get explained by any of these guys, just pointed out - with the statistical sophistication of an astrologist. The latest effort at WUWT includes drawing a fat yellow horizontal line over an uplsoping trend of ocean-heat content and calling it a pause in global warming, a challenge to AGW. How is that not pseudoscience, by any definiton?
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Composer99 at 10:33 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Habilus:
I am fairly certain this is the third time today I have noted that someone has misunderstood the ad hominem fallacy. Tom Curtis & I were both rather pert with you, that is true. However, we also addressed the substance of your claim (insofar as there was any to begin with). We would have committed the fallacy only if our responses had solely been our concluding remarks.
(Interestingly, I came across this essay while looking for a concise definition to use above which argues that there is no ad hominem fallacy.)
I still don't see where the problem with Australia losing out on carbon ETS (to be accurate) revenue is, insofar as it results from Australian individuals, families, and businesses reducing their carbon usage more aggressively than the government projected. And as Tom Curtis notes, the Australian government diverts the ETS revenue into payments to Australians to offset cost increases from the scheme. So if the ETS generates less revenue than generated, I suppose that less money would be paid out - but this would balance out as reduced carbon usage by Austalian individuals, families and businesses means they are not affected as much by costs passed downstream by emitters.
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scaddenp at 10:13 AM on 6 March 2013Why SkS withdrew from the Bloggies
Hmm, Weart is great account of the historical background. SoD "insigificant trace gas" series is great introduction to basic physics, but for overview of science, it's hard to beat the IPCC WG1 report.
There is no talk of "closing blogs" - how could you? But if you are interested in scientific truth as opposed to ideology-driven anti-science why would bother to read sites that misinform? (and I would hasten to add that Spenser and Curry arent in the sewer with WUWT). The usual reason is to seek confirmation of what you hope is true. A science education is about training the mind on how not to fool yourself.
Discussion on models belongs in the "Models are unreliable" thread. However, there are some caveats to observe when thinking about GCM models. While purposes overlap, there are two reasons for creating computer models. We could be realising well-established conceptual models for a useful purpose (eg tomorrows weather or plotting a probe to Hyperion). Or we could be testing our conceptual models by checking computation against observation. GCMs are used for both but differences in intent change what is actually done. In both cases, comparisions or predictions have to be made against uncertainties inherent in both the computations from the models and in the measurements of the real world. This leads to very different levels of robustness about predictions. In evaluating models, it often better to think of model skill (performance of model predictions compared to null hypothesis). Current GCMs have no skill at decadal level prediction for instance. They have considerable skill in many other areas.
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Philippe Chantreau at 09:45 AM on 6 March 2013Why SkS withdrew from the Bloggies
I will stop comparing climate science with Quantum theory if you stop making meaningless arguments about the "age" of an area of science.
Your "endemic problem" is BS. Fake skeptics' theories are mutually exclusive ("i.e. it's the sun" and "climate sensitivity is low") and have no grounding in reality. They're made up according to the need of the moment. Nothing follows in the litterature that is worth considering. In an effort of your own rethoric, youonly cite various wordings of what is the same thing, without showing that the thing was any different. I'm unimpressed. As for the "snowfalls are a thing of the past", I have never seen any such statement from a source that is worth reading. Considering the enormity of it, please provide a source.
Watts' problem is not one of communication, it's one of incompetence:
http://wattsupwiththat.com/2009/06/09/co2-condensation-in-antarctica-at-113f/
Not only did they give this much serious consideration, but the peanut gallery in the comment thread keeps on ridiculing the people trying to inject some sense in the discussion, the kind who could understand the phase diagram. That's a legitimate source to you? Really?
I still go read these posts when I need a good laugh. In subsequent ones they do little high school experiments and eventually conclude "it seemed like a good idea at the time."
Now please explain to me how these buffoons add quality to any kind of debate about science. Goddard was described by Smokey as writing "informative posts."
Eventually Watts had to distance himself from Goddard's incompetence in an effort to keep up appearances. That's too bad, it was more entertaining when he was on. board...
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Bob Loblaw at 09:32 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus:
You've bought into Judith Currie's "uncertainty monster", and unfortunately you don't have the knowledge to recognize it for what it is (which is not much). The sources you are using are seriously overblowing the significance of the uncertainties.
You've been asking about sources summarizing climate science. I suggest you try reading Spencer Weart's The Discovery of Global Warming.
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keithpickering at 09:28 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
The .pdf link is dead to me, and no cache is available. The supplemental info and data are available at the PNAS website.
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uknowispeaksense at 09:15 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
However, opposition leader Tony Abbott has said that the election in September of this year is a "referendum on the carbon tax," and at the moment he appears to have a lead in the polls. So far the impact of the carbon tax on the Australian economy appears to be minor, as expected, while both carbon emissions from the electricity sector and energy demand have fallen recently. In short, the carbon tax is working well, but there are worrying signs that it may nevertheless be repealed as a result of the upcoming election.
I initially examined Hansard, which is the record for the Australian parliament, personal websites, interview transcripts and press releases looking for definitive statements by every current member of both houses of parliament that demonstrate their individual positions on the science underpinning climate change. Links to both pages can be found here. I also extended that to look more closely at Tony Abbott's shadow cabinet team and it doesn't look very good for any environmental policy should his party be successful in the federal election in September. That page is here. That said, my understanding is that Abbott will find it very difficult to repeal the carbon tax given the effort big business, the traditional conservative support base, has put in to accommodate it in their business plans. Much work has also gone in to their long term future planning also. It will be too messy. Abbott and his team will spin it however they see fit to backflip on the promise to repeal, knowing the electorate has a short memory.
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uknowispeaksense at 09:10 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
However, opposition leader Tony Abbott has said that the election in September of this year is a "referendum on the carbon tax," and at the moment he appears to have a lead in the polls. So far the impact of the carbon tax on the Australian economy appears to be minor, as expected, while both carbon emissions from the electricity sector and energy demand have fallen recently. In short, the carbon tax is working well, but there are worrying signs that it may nevertheless be repealed as a result of the upcoming election.
I initially examined Hansard, which is the record for the Australian parliament, personal websites, interview transcripts and press releases looking for definitive statements by every current member of both houses of parliament that demonstrate their individual positions on the science underpinning climate change. Links to both pages can be found here. I also extended that to look more closely at Tony Abbott's shadow cabinet team and it doesn't look very good for any environmental policy should his party be successful in the federal election in September. That page is here. That said, my understanding is that Abbott will find it very difficult to repeal the carbon tax given the effort big business, the traditional conservative support base, has put in to accommodate it in their business plans. Much work has also gone in to their long term future planning also. It will be too messy. Abbott and his team will spin it however they see fit to backflip on the promise to repeal, knowing the electorate has a short memory.
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Eclectikus at 08:56 AM on 6 March 2013Why SkS withdrew from the Bloggies
Sphaerica #103, you understand what you want understand. I read WUWT, and when I do I know what I read. I also read SkS, SoD, Climate Audit, Roy Spencer, Curry, and some more. Are you claiming to close all blogs except SkS and realClimate?
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Eclectikus at 08:50 AM on 6 March 2013Why SkS withdrew from the Bloggies
104 # Leto. Please take a look the video I posted in #43, and you'll see where I take this "weird definition".
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Eclectikus at 08:40 AM on 6 March 2013Why SkS withdrew from the Bloggies
Thank you scaddenp, I take note and I probably come back with some questions in different areas I have, basically about confidence in models and on several sources of uncertainties recognized by NASA itself: http://climate.nasa.gov/uncertainties/
In order to be reasonably informed in a particular issue, reading the papers in the journals is a excesive time consumer, for my is more easy go to selected works pointed out here or there, and reading what people more engaged have to say on particular threads in several blogs. I think is a very good option that Internet offers to all of us, people no directly implicated on Climatology. I read often Roy Spencer (and also Steve McIntyre), less Real Climate, and I didn't know about Issac Held... bookmarked, you see? always is possible to get something clean. Thanks.
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Leto at 08:35 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus wrote:
"In Feynman's sense, theories that are unable to explain empirical values, and in this sense (and only in this sense) Climatology could be tagged as pseudoscientific."
I am often struck by the parallels between climatology and medicine. Both deal with imperfect data and complex systems. Both have to make predictions and recommend solutions without the luxury of waiting for perfect information and a complete theory that will never come. Both have to fend off attacks by fringe theorists who claim to know better than those who have actually done the hard yards and, you know, studied the subject. And, of course, both are "pseudoscence" by your weird definition. This suggests your definition is not very useful.
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Bob Lacatena at 08:10 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus,
...we're far to have a working model of the earth climate.
False. This is one of the denier's mantras. "We don't know enough!"
B.S. Go read. I already told you, you don't actually understand enough of the science to adopt the position that you have. But rather than learn more, you claim to know everything you need to know, and supplement your ignorance by reading WUWT.
For shame.
I really do not understand why it is so hard to accept this position... is there any other coherent position?
That's because you don't understand the science, so you read all sorts of emotional (and false) nonsense that you see on B.S. sites like WUWT. The foundation of your position — that climate science is weak, that the IPCC is corrupt, even that there is some sort of debate about the science itself — is undermined by reality. You can't see that, though, because instead of educating yourself, you come here to pontificate, or go to WUWT to get even more confused about the state of the science.
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JoeT at 07:43 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Further to my post @19, Pierrehumbert says his views are in line with those of Larry Cathles. Here's an article about the Cathles/Howarth argument. Also, here is the published paper.
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dhogaza at 07:29 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin:
"This is a peer reviewed paper showing that CO2 lags behind temp."
And this, much more recent, just published in Science, shows that actually it hardly does at all:
Parrenin, F. V. Masson-Delmotte, P. Köhler, D. Raynaud, D. Paillard, J. Schwander, C. Barbante, A. Landais, A. Wegner and J. Jouzel, 'Synchronous changes of atmospheric CO₂ and Antarctic temperature during the last deglacial warming', Science, 339, 1060-1063, 2013.
It would be a good paper for SkS to write about.
Kevin, regarding the whole Milankovic cycles, CO2 feedback, etc, this is all so 1990s denialist argumentation that has been undermined by climate science for a very long time. The paper I cite above compresses the time scale in which CO2 rises as a result of Milankovich-cycle forcing causing the earth to warm, which emphasizes that this rise leads to a feedback affect accelerating that warming.
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Chris Colose at 07:26 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
There's several points of confusion in the above comments, most of which miss the timescales being discussed in the paper, which (by and large) is a bit longer than orbital. From a last ~60 million year perspective, CO2 is pretty clearly a big forcer of the gradual cooling we've seen over the Cenozoic and in the development of the great ice sheets. You can say it's a "geologic feedback" in the sense that the CO2 responds to things like plate tectonics, mountain uplift, rate of organic carbon burial, etc However you define a reference system, you can call something a feedback, but it doesn't change the physics that we don't have a way to get from the climate 60 million years ago to the climate today without changing the CO2. On the glacial-interglacial timescales, you have to be careful, because the orbit is pretty clearly pacing the changes and the impact of CO2 becomes progressively more important as you move equatorward (e.g., in the CMIP5 models for example there is a more coherent negative correlation between model climate sensitivities and their tropical averaged LGM temperature anomalies, as opposed to the global mean anomalies...it doesn't really matter in this sense whether the orbit or the CO2 comes first, radiation still works...but the CO2 pretty clearly comes after Antarctic changes but before global-mean changes). But the ice sheet changes can't be tied to just CO2, so I wouldn't out much stock in the paper on orbital timescales.
On the geologic timescales when you sample over lots of orbits, you still have to be careful applying the results from the paleo-record to the future, because there's almost certainly hysteresis in the ice sheets (e.g., whatever concentration of CO2 helped you glaciate Antarctica is almost certainly a different concentration of CO2 than you need to deglaciate Antarctica) and the rate of change probably matters too. Some of these issues aren't well-sampled given the time resolution and (rather one-way) temperature evolution over the last 40 million years.
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DSL at 07:13 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Should I repeat the concept for a fourth of fifth time? CO2 is CO2. It doesn't matter how it gets into the atmosphere. If we put it there, it is considered a forcing. If it gets there through ocean warming, it is considered a feedback. That whole "CO2 lags temp" meme is one of the goofiest.
And, again (because you did not read what I wrote the first time), orbital forcing starts the glaciation/deglaciation process. Once the process begins, the initial orbital forcing is overwhelmed by feedbacks. The primary feedbacks are, for glaciation, increasing ice/snow-albedo effect and decreasing ocean temp (increase in CO2 uptake). The primary feedbacks for deglaciation are warming oceans (decrease in CO2 uptake) and decreasing ice/snow albedo effect. Both processes are modified slightly by, respectively, associated changes in the biosphere (respectively, a decrease in biosphere uptake of CO2 and an increase in biosphere uptake of CO2). Water vapor is a fast feedback and so doesn't enter into the conversation about climate-scale forcings and feedbacks.
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Composer99 at 07:05 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin:
CO2 lagging temperature applies where its emission by sources or absorption by sinks is temperature-dependent: CO2 emission from or absorption by the oceans, CO2 absorption by rock weathering, and similar processes.
By contrast, CO2 leads temperature when its emission by sources is temperature-independent, such as emissions from volcanism (which has been a trigger for past warming, if not in the Pleistocene) and, since the start of the Industrial Revolution, the massive bolus of fossil carbon emitted by humans. (I am not personally aware of any temperature-independent carbon sinks, although perhaps the kinds of biological sinks that lead to the creation of fossil fuels count.)
The correlation between sea level and CO2 is unsurprising because either the small orbital forcing (as in the Pleistocene) is magnified by the greenhouse effect, allowing sea levels to rise or fall in tandem with CO2 concentrations, or (as in the modern period, or perhaps warming out of Snowball Earth conditions when temperature-dependent absorption of CO2 is inhibited while vocanic emission continues apace) because CO2 emissions are driving both temperature changes and sea level changes.
As far as I can see, the paper you link to explains in published form exactly what I was describing in #10. If you wish to pursue further discussion along the lines of "CO2 lags temperatures" I suggest this thread.
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ubrew12 at 06:56 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
A control knob is not a switch. Alley is saying if you can control CO2, orbital effects will have little effect. Go ahead and throw the switch, if the oven is turned down little is going to happen. The mechanism whereby CO2 drives temperature can be proven in your garage. The mechanism whereby temperature drives CO2 is speculative, involving ocean outgassing. I believe it and so do you, but if you're going to get hung-up on causation, that should be your candidate. Once CO2 levels increase, temp and sea level have little choice but to respond in kind, because of that thing you can prove in your garage. So the lag you notice is evidence of a different switch, but the response has little choice but to reflect the control knob. That the control knob can also be a switch shouldn't be hard to imagine. In the last 150 years, thats been the case.
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Rob Honeycutt at 06:42 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Habilius... And how much is the expected shortfall? You're bandying about the $24B figure like that's the shortfall. That's the budgeted revenue.
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Kevin8233 at 06:41 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
ubrew12,
but the paper I showed you shows that CO2 lags temp, that temp is the driver of CO2 levels, not the other way around.
We know that ice ages and interglacials are caused by orbital effects,
That was one of my first points, that it was somewhat ridiculous to call CO2 the big control knob, when the ice ages were caused by other factors.
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ubrew12 at 06:35 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin@10: Composer99@5 tried to inform you: through the greenhouse effect CO2 is a powerful feedback as well as forcer. Claiming otherwise refutes the greenhouse effect. We know that ice ages and interglacials are caused by orbital effects, but CO2 is a powerful feedback that enhances (i.e. causes) much of the enhanced response; the greenhouse effect demands it do so. Hence, I can't claim that the historical rise and fall of sea level was caused by CO2, but I can claim that the AMOUNT of that response WAS caused by CO2 level fluctuations.
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Habilus at 06:33 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
@Tom Curtis and Composer99, happy to draw your ad homenim.
Regardless where the money was to have been spent, Australia bugeted a $24 billion income from the carbon tax over 4 years. The shortfall will have to come from somewhere. Maybe they can borrow it from China like everyone else.
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Kevin8233 at 06:19 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
ubrew12,
http://www.sciencemag.org/cgi/content/abstract/283/5408/1712
This is a peer reviewed paper showing that CO2 lags behind temp.
We shouldn't have to argue that point! So, your are saying that it is a correlation, not causation, but then you go on to mention that CO2 causes high sea level change via the greenhouse effect. So, you are arguing that it is a causation relationship.
That is complete nonsense! The above paper shows that.
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Eclectikus at 06:13 AM on 6 March 2013Why SkS withdrew from the Bloggies
Composer99 at #100. I'm not sure in which fallacy falls this argument, ad populum or ad verecundiam. Maybe is a mixture.
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Habilus at 06:07 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Key Point #4; ",... and the Earth is once more in equilibrium."
At what point in graph 'A' was the earth in equilibrium?
Moderator Response: (Rob P)- The scale of the graph is not detailed enough to show this, but the 400-500 year-long Medieval Period is a good example. Sea level volume was static during Medieval time because it wasn't warm enough, in a global sense, to add noticeable glacial meltwater to the oceans, nor sufficiently cold enough to grow land-based ice. -
scaddenp at 06:03 AM on 6 March 2013Why SkS withdrew from the Bloggies
"Could someone be so kind to tell me where could have a more or less continuous view of the debate? (from a critical position I mean)... or simply it does not exist, everything is closed, and I should read SKS and SoD only."
What those blogs have convinced you by their misrepresentation is that a debate exists. In your sphere of geophysics (mine too), science debates take place in the journals. That is where they belong. Climate science is debated in the journals but 99% of what is in debate is of no interest to WUWT crew because it would not have a policy outcome that is favourable to the authors or readers.
Now if you think otherwise, and there is substantive debate over validity of climate science, then I suggest (as others did), that you put up your evidence (in an appropriate thread here). In the subsequent discussion, then perhaps it will become clearer whether you have been misled or whether we have.
If you want to know what happening in the science from blogs, then read blogs written by practising publishing climate scientists. That would include Roy Spencer but also RealClimate, Issac Held, Chris Colose to name a few. SoD is really about what's in the textbooks not the journals. Very very good for the basics.
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ubrew12 at 05:55 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin@7: "Foster & Rohling (2013) ... found a consistent and robust relationship between carbon dioxide and sea level"
Correlation is not proof of causation. The mechanism whereby high CO2 causes high sea level, however, is called the greenhouse effect, which neither this website nor any other should have to defend, at this point.
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Composer99 at 05:52 AM on 6 March 2013Why SkS withdrew from the Bloggies
Eclectikus:
If you're going to characterize an appeal to the actual evidence (you know, the atmospheric physics & chemistry, ocean chemistry, radiative physics, empirical observations, and so on) and to the pros who work with such evidence regularly as "who is closer to orthodoxy" then I submit that, contra your assertion, I'm not the one here who is arguing in bad faith.
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JoeT at 05:47 AM on 6 March 2013China Takes a Leading Role in Solving Climate Change
Physicist@12 Raymond Pierrehumbert, whose opinion I always pay attention to, called the Howarth study "seriously flawed" (under comment #20). You can also find a more extended comment by Gavin Schmidt here
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Kevin8233 at 05:41 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
How about the first question? Is fig 1a a cause and effect figure?
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Composer99 at 05:37 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Oops, forgot to work with WSIWYG when including links.
Also, DSL basically posted a much more concise, therefore superior, version of what I did.
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Composer99 at 05:30 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin:
Short answer: No, no overreaching. Richard Alley's characterization is correct. Watch his video, read the link in the OP on Milankovitch cycles, and read <a href="http://pubs.giss.nasa.gov/docs/2010/2010_Lacis_etal.pdf">this paper</a>.
Long answer:
WIth regards to the specific timeframe you mention, the Pleistocene, and its variation between glacial periods (massive ice sheets covering large segements of North America & Eurasia - the stereotypical Ice Age) and interglacials (ice largely confined to polar & alpine areas), orbital wobbles which alter the amount of summertime sunlight reaching mid-high latitudes in the Northern Hemisphere (around 65°N).
When cooling into a glacial period, the wobbles act so as to reduce summertime solar insolation at this latitude, allowing snow to persist for longer and reflect more sunlight (snow having a greater reflectivity than the underlying terrain), which causes cooling. When warming up into an interglacial, the wobbles act so as to increase summertime solar insolation, starting the process of melting the continental ice sheets.
What is critical to note is that the change in forcing in these orbital wobbles is, in and of itself, nowhere near significant enough to cause cooling sufficient to form continent-wide ice sheets, nor to cause warming sufficient to melt them.
As noted in the OP, CO2 feedbacks then kick in, which themselves trigger additional feedbacks. The net effect of the feedbacks follows the direction of the initial change in forcing.
Over the course of the Pleistocene, until the onset of the Industrial Revolution, CO2 concentration in the atmosphere can largely be attributed to this process, with some minor contribution from volcanism and sequestration from other geological processes.
The critical point is that, as shown in the Lacis et al paper and the discussion of Pleistocene glaciation, CO2 is indispensible to the mediation of Earth system climate. Orbital wobbles have not always been an important forcing in climate (given the resolution studies of paleoclimate affords us), and solar forcing, while ultimately important, has to be mediated by greenhouse forcing in order for the Earth climate to support most life as we know it (some cold-resistant bacteria or other simple organisms notwithstanding).
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DSL at 05:13 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
But the cached version does appear.
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DSL at 05:12 AM on 6 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
The Foster & Rohling link is a dead end.
Moderator Response: (Rob P) Fixed thanks.
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