In light of the Fumento furor here I thought it might be useful to point out an example of what appears to be scientific skepticism done right, on a controversial topic with significant ethical and policy implications. Not virtiolic personal attack or 'gotcha' fact selecting, but a carefully reasoned alternate hypothesis to the reigning politically correct one, based on a coherent and plausible interpretation of validated data.
Recently retired from the University of Virginia, William Ruddiman is one of the world's most highly respected paleo-climatologists. In recent papers, an article in Scientific American and now in a book for laymen, he argues that pre-industrial agriculture, with its deforestation of vast areas in the Old and New Worlds and the rapid spread of rice cultivation in Asia, released suffient amounts of carbon dioxide and especially methane into the atmosphere to fend off what would otherwise have been a new period of glaciation -- a new ice age. But don't gas up the SUV in triumph quite yet. There's still both a scientific and a policy debate to be had.
I have a copy of Plows, Plagues and Petroleum: How Humans Took Control of Climate speeding on its way and will review it when it arrives. In the meanwhile, you can read Ruddiman's 2003 paper here, his 2005 article in Scientific American (available here for a fee) and a polite discussion of some of the technical issues here.
The abstract of Ruddiman's 2003 paper summarizes his argument:
The anthropogenic era (ed. - ie climate warming due to human intervention) is generally thought to have begun 150 to 200 years ago, when the industrial revolution began producing CO2 and CH4 at rates sufficient to alter their compositions in the atmosphere.A different hypothesis is posed here: anthropogenic emissions of these gases first altered atmospheric concentrations thousands of years ago. This hypothesis is based on three arguments.
(1) Cyclic variations in CO2 and CH4 driven by Earth-orbital changes during the last 350,000 years predict decreases throughout the Holocene, but the CO2 trend began an anomalous increase 8000 years ago, and the CH4 trend did so 5000 years ago.
(2) Published explanations for these mid- to late-Holocene gas increases based on natural forcing can be rejected based on paleoclimatic evidence.
(3) A wide array of archeological, cultural, historical and geologic evidence points to viable explanations tied to anthropogenic changes resulting from early agriculture in Eurasia, including the start of forest clearance by 8000 years ago and of rice irrigation by 5000 years ago. In recent millennia, the estimated warming caused by these early gas emissions reached a global-mean value of ~0.8ºC and roughly 2ºC at high latitudes, large enough to have stopped a glaciation of northeastern Canada predicted by two kinds of climatic models. CO2 oscillations of ~10 ppm in the last 1000 years are too large to be explained by external (solar-volcanic) forcing, but they can be explained by outbreaks of bubonic plague that caused historically documented farm abandonment in western Eurasia. Forest regrowth on abandoned farms sequestered enough carbon to account for the observed CO2 decreases. Plague-driven CO2 changes were also a significant causal factor in temperature changes during the Little Ice Age (1300–1900 AD).
Ruddiman's critique embodies several key factors. First, he identifies key data that do not appear to be well-accounted-for in the popular theory (i.e. that current warming of the globe is the result of industrial activity including petroleum-based transportation). Second, in the body of the paper he analyzes that theory and demonstrates why it does not adequately account for the data. And third, he offers an alternative hypothesis which not only accounts for the climatic data but which also accords with emerging data from other disciplines (paleontology).
The result is a mature work which has gained the attention of many in the scientific community. It forms the basis for a possible debate regarding public policy in response to global warming. For the science doesn't make the issue go away -- it merely illuminates the nature of the various forces whose current balance led to an unprecedented 8000 year period of climate stability.
Ruddiman notes that human contribution to global warming in the 200 years or so since the start of the industrial age is equivalent to all previous contributions in the thousands of years from the start of agriculture to that point, and it is increasing. Will the natural cycles which would otherwise plunge the Earth into a period of glaciation, a new ice age, overwhelm that warming contribution? That is a question for science-based modeling and prediction. And if the models suggest that will happen, how long would it take and what changes in our environment would occur along the way if we do not take action to reduce our production of carbon dioxide and methane? How much could we slow the rate of warming if we tried and are the costs of such an attempt worth the likely outcome?
These are policy issues which need input from careful science. The discussion at realclimate.com that I linked above is one step towards that input, as Ruddiman's techniques for analyzing the data from Earth's past are evaluated for soundness and completeness. Other data may also be brought into the analysis. For instance, in the April issue of Analog magazine, Science Fact author and physicist Richard Lovett notes a 2005 paper by Matthew Sturm and colleagues that suggests that Ruddiman's model underestimates the impact of changes in Arctic vegetation on climate -- impacts which not only corroborate but strengthen his argument.
If Ruddiman's work demonstrates major flaws in the politically correct theories of recent human responsibility for climate change, it by no means should leave us complacent. Human civilization has flourished for the last 8000 years precisely because of a benign and stable climate in many parts of the world, a climate which was the result (if Ruddman's hypothesis is correct) of human activity (warming) balanced against the natural cycles of the earth in its orbit around the sun (at present, cooling). But Ruddiman notes that the human side of the equation has accelerated. CO2 levels in 2006 have reached levels the earth hasn't seen since the age of the dinosaurs. We are, Ruddiman says, heading into terra incognita. His work has, however, given new insights into climate change and, as his hypothesis is evaluated in detail, may help to inform policy decisions around the world.
"Human civilization has flourished for the last 8000 years precisely because of a benign and stable climate in many parts of the world, a climate which was the result (if Ruddman's hypothesis is correct) of human activity (warming) balanced against the natural cycles of the earth in its orbit around the sun (at present, cooling)."
Huh? Ok, in the sense that the Earth didnt boil up like Venus, mankind can be said to have benefitted from a stable climate- but I think its a pretty speculative assumption to claim that either the Earth has been particularly stable over that period or that that had much to do with the success of our various civiliations.
If a stable or mild climate was the key to human success, why then did tempestuos Europe lead the way in the advent of modern civilization? Why didnt the Aztecs enjoying the beautiful Pacific coast thrive and the Germanic tribes freeze? It seems to me that if climate is incredibly complex, mankinds relationship to it is even moreso. Humans seem to thrive in all sorts of radical climate variations.
The only way to make this argument is to assume it is likely that the earth could be radically different in global climate on the time frames in question, and that has always been the sticking point between the pragmatic investigators of global warming and the alarmist activists. The only way AGW is a danger worthy of massive resource reallocation is if climate change will be abrupt, radical, and destructive beyond our ability to manage it- and magically all the activists scenarios manage to migrate to that outcome. But that doesnt mean its realistic, much less that humans have been particularly 'lucky' over the last 10,000 or so years (aside from a catastrophic asteroid impact etc of course).
Mark, read Ruddiman's paper for the argument on what the climate would have been like without agriculture. Ruddiman qualifes as a careful investigator.
While there has been variability, obviously, on a smaller scale (such as the cooler/drier period that probably pushed humans to begin agriculture in the first place as hunting became harder), we've had nothing like the rapid changes that could be expected. To quote Ruddiman, "humans stopped a glaciation". Another ice age would have made civilization as we know it impossible.
Yes, alignment of current with past cycles is a critical part of doing this science correctly. Fortunately, as Lovett notes, the lowest couple feet of the Vostok ice cores give data from the last period in Earth's history that most closely aligns with our current place in the 3 cycles (axis tilt, precession and ellipticality of orbit) that determine cooling and heating at a macro level. Those samples confirm Ruddiman's analysis.
I linked to realclimate.com to illustrate that even those who have held the "it all started 200 years ago" theory are taking Ruddiman's analysis seriously. It's not my field of expertise, but judging from the impact his recent analyses have had, he's on sound footing.
Molone,
When you use the phrase "politically correct" to modify climate theories at the beginning and end of your post, you raise suspicions that you are on a hunt for theories that are not "politically correct." Good science requires you to follow the facts, not search for facts that will support or refute a theory that you like or don't like because of its political implications. Such a search inevitably leads to a selective use of facts...or an outright selection of facts.
Your search reminds me of those who oppose the theory of natural selection and are out on a scavanger hunt for odds and ends that will support some alternate theory that they are more comfortable with. It's an odd way to approach the inquiry.
Either you missed my point or I wrote in a less than clear way. Heidi Cullen wishes to enforce a politically correct view with regard to climate change on meteorologists who do weather broadcasgts. Fumento appears to relish being politically incorrect for its own sake. In contrast to both of them I put forward an example of a much more responsible and effective way to critique a currently popular theory while advancing our understanding in useful ways.
I'm on no mission to find theories that are either politically correct or politically incorrect. I'm on a mission to find out about the best science being done so that I can base my opinions regarding important policy issues as much as possible on well-founded theories and carefully documented and analyzed facts.
Unfortunately, it's not obvious that the same thing can be said for some who are advocating major policy action with regard to global warming -- or for some who have what appears to be a knee jerk reaction against the same.
The world of meteorology / climate studies does have an unfortunate political element. Consider this news article:
It's the last clause that matters here. The UN body that claims to speak authoritatively on climate change may well be - and based on other scandals about UN corruption, this seems credible -- corrupt at the top. In such an organization, it's not hard to suspect that corruption also might influence climate analyses, given their major economic implications for various countries and industries.
Add in the Oscar nominations for Al Gore's film and the politicized nature of the climate change debate seems pretty evident to me. All the more important that we have mature, well-grounded and well-reasoned hypotheses such as Ruddiman's as an alternative basis for policy discussion.
Ruddiman's critique may embody the points you claim- but that is not supported by anything provided in the post.
Frankly, it looks like you're knocking down a "popular theory" in the same way that I might point out that, while the popular theory suggests the Industrial Revolution began with the steam engine, historians in fact date the beginning to the increased sophistication of cloth manufacture and trading in England c. 1150.
I suspect this will all sort itself out in the not-too-distant future as the size of what is at stake becomes apparent to more people.
Molon,
I'm sorry, but I am just not buying your claimed stance of objectivity here.
You are confusing science with advocacy. You seem to dislike the advocates, those you call knee-jerks, those named Al Gore, those who think policy should be adjusted to try to reduce the factors believed to cause global warming.
You are using that dislike to claim that the science behind their advocacy is in need of review--or is itself politicized. I don't believe that is the case.
There is a mountain of good science that says 3 things:
1. the earth has warmed over the last 100 years.
2. the warming has accelerated over the last 13 years.
3. burning of fossil fuel contributes to both 1 & 2.
There's nothing murky about that.
Predictions about the future are murkier and there is less agreement among scientists about what might or might not happen, the range of possibilities and the liklihood of occurence.
After that comes all the advocates and politics. This seems to be your concern. How others use the science. Better science won't help. There will always be alarmists and there will always be those in denial. But the science will keep plugging away.
As the latest IPCC report will be out soon we will no doubt see some very heated debate about anthropogenic climate change.
While the theory you describe is interesting for those of us scientifically inclined, the general population will likely overlook it and policy makers are not helped by it.
The struggle before us is how to balance the claims of: (1) those wanting to tax the 'sin' of carbon in an attempt to reduce carbon emissions, (2) those who will want to use law or force to physically reduce the use of carbon fuels, and (3) those who think #1 and #2 are on a wrong track (for a myriad of reasons).
The #3 group above could conceivably use your referenced work to show that man has indeed been helping himself so far... so mankind should not be cast into purely evil terms (as is commonly practiced by certain groups.)
If oil and natural gas production is indeed peaking globally (say in a decade long window in which we currently find ourselves), that will mean even stronger growth for coal, the use of which has been growing strongly anyway. Thus the CO2 problem is likely to accelerate.
The potential exists for local, national, and international politics to change significantly, with lots of new bedfellows.
I'm waiting until after the SOU address, and the IPCC release a couple of weeks later, to go into more detail... and to see how blog-spheres-of-influence (such as W.O.C.) react to all of this. Will our policies and practices change?
sc and mark-
I'll point out that your responses to Molon are essentially religious in form, rather than scientific in any sense that I know it (and I speak as someone who, while unconvinced that the global warming we're seeing is as significantly anthropogenic as claimed, thinks we need to act as if it is because the risk of being wrong is just too great). There's a serious question in front of us, and it isn't as well established as, say, quantum mechanics. And in response to Molon's post,instead of making arguments, pointing at data or at others who have summarized arguments or data , you sure sound like you're looking for protestations of faith instead.
A.L.
But that's exactly the point mark, a 'mountain of good science' can and should be destroyed in an instant by one scientist who get's it right.
Good science routinely gets made obsolete by even better science. It's an essential part of the process. What's going on in the more politicized arenas however is that people are advocating revoking the credentials (i.e. stop listening) to people questioning the good science. When that happens you've thrown the whole scientific method out the window and changed over to orthodoxy.
There are credibility issues of course in who you listen to (how to seperate the crackpots from the real scientists) but solutions for that have existed for a long time now, the problem is those solutions are breaking down, or more accurately, aren't being applied properly when the issues are discussed in the general populace.
This really is an excellent, and thought provoking, example of proposed 'better science'. Whether it will replace the 'good science' depends on how the peer review and follow up work goes.
After observing this controversy for a few years now, I think the global warming debate as we know it has just about run its course, and will end not with a bang but with a slow, drawn-out whimper. The new Democrats in congress will romp with it for a while, which will only hasten its demise.
The huge grants will dry up, the activists will take their agendas elsewhere, and the field will shrink to natural proportions. Only then will we have a full assessment of all the honest science that has been done on this issue, minus the doomsday scenarios and the Lysenkoism.
At that point we will either have a good assessment of how human civilization has effected climate change, or we will have a new consensus, possibly one that says such change is incalculable or insignificant compared to natural mechanisms. Science, after all, has to be prepared for such reversals. Politics can't accept such things, it has to perpetuate its mistakes, or adopt new fantasies to justify old ones.
In pushing this into a policy debate, science runs right out of its area of expertise. International agreements will not stop global warming any more than they have stopped war, especially not agreements that place radical and inequitable burdens on nations. Such agreements will instead lead to increased hostility and finger-pointing.
The world would need a mighty compelling reason to conclude that climate change is a bigger threat than underdevelopment and poverty (and the wars that follow them) and they would need assurance that draconian policies will make things better, not worse. Hence Gore and his Doomsday scenarios, which have as their moral the idea that the choice is between privation (and rule by "international" fiat, politically congenial to the meddling class) and death. In a few short years such things will be looked on with derision, as we look back on the jeremiads of the 60s and 70s. Thanks to them, the debate will always carry that taint.
We're not going back to Solitary, Poor, Nasty, Brutish, Short, and Cold.
A.L.
Your claim that my response was religious in form, while interesting, wasn't followed up by an explanation of how or why anyone else should see it as such. Obviously, my response was not scientific--it was not meant to be as I wasn't making a scientific point. I was and am arguing that Molon's post and subsequent defenses of the post are filled with transparent political motivations and, thus, deeply suspicious. Further, that his claims of objectivity are undermined by his own presentation.
There's a lot of doctor shopping goining on here. And it seems to be based not on a disastisfaction with the diagnosis, but a disastisfaction with the types of people who use the diagnosis to recommend distatesful remedies. To me, this seems plain silly.
A side question: why would anyone use anthropogenic instead of man-made. To me, this seems plain silly.
Nothing I posted or linked to disagrees with that, mark. But neither is that adequate as a basis for making policy decisions -- and in particular, for detailed policy tradeoffs. Because there ARE tradeoffs inherent in any action (or inaction) we take with regard to fossil fuel use. The only question has to do with the nature and extent of those tradeoffs.
By refining in a significant way the previous models of climate fluctuation, one of the world's most respected paleoclimatologists has moved us closer to being able to identify and quantify those tradeoffs. Sounds like good science to me.
Nor am I against serious policy decisions on matters that affect climate change. I do, however, want them based on the BEST science we can muster.
why would anyone use anthropogenic instead of man-made.
Ruddiman uses 'anthropogenic' because it is the standard term in the research literature on this topic. That it seems "silly" to you says something about your familiarity with research in climatology, but not about the term itself or about its use by Ruddiman.
Google Scholar (not a full citation database of all the scholarly literature, but representative) lists these papers by Ruddiman. For those not familiar with scholarly research literature, one of the impressive things about his publications is how often they are cited in other works. And not just one paper, but paper after paper of his have been cited many times in the literature.
Ruddiman is no johnny-come-lately with a political ax to grind. He is a seminal scholar with a very distinguished research and publication career, now retired and in no need of research funding or other patronage. The care with which he analyzed the data and previous models, and the solid foundation for his new model, illustrate why he and his work are so respected.
Treefrog,
I think you missed my point, probably on account of my mediocre presentation of it.
I'm not suggesting that "settled" questions shouldn't be examined. Obviously, by its very nature, the scientific endeavor continually improves itself and that new theories--and improved theories--result from new information. That is the very essence of science.
I have absolutely no informed opinion of Ruddiman's theoy. From Molon's account it seems to have no direct bearing on the so-called debate about global warming. My compaint is that Molon's advocacy of this theory seems to be based only upon Molon's desire to debunk Al Gore's followers. This is not a good reason to take sides in a scientific enquiry.
To me, this is Intellegent Design all over again. "I don't like the implications of natural selection, so I shall declare the question open and anyone who challenges alternate theories I shall accuse of orthodoxy and intent to stiffle scientific debate."
If the science is bad, attact the science. But don't attack it because you don't like the conclusions or the purposes that other put it to.
When the science is a complicated and as full of variables as climatology it is easier to fact select to make arguments. I am very distrustful of those who promote or advance a theory when they are obviously motivate by political factors or forces.
Molon,
Read my post above to Treefrog. I have no complaints about Ruddiman's theories, if for no other reason, than I have no knowledge about his positions. I am not attacking him. My complaints have all been about your presentation, which I found to be politically-motivated and thus suspect.
I'm aware of the sadly frequent subsitution of anthropogenic for man-made. It's another example of how scientists are only human---oooops, I mean members a branch of the anthropodea.
mark, the desire to debunk Gore is something you are projecting onto me, not something I actually feel. I think Gore is a pompous ass who is obviously embittered by his election loss, but that doesn't make his advocacy re: global warming wrong.
Neither, however, does his fervor make it right.
What is missing in this whole back and forth is science that accounts for all of the data we have to hand so far about the various contributing causes of climate change over time. Ruddiman provides an important addition to that science. It remains to be seen how additional analysis and data reinforce or modify his conclusions about those forces.
Please refer back, again, to the place where I quote Ruddiman as saying that recent human activities are moving us into terra incognita with regard to the balance between the natural cycles of the earth's climate and human warming activities. That sure as hell doesn't sound like sniping at Gore to me.
If I may clear up what appears to be a misunderstanding, I made reference to 'politically correct' theories at the start of this post as a segue from the Fumento furor. Fumento prides himself in being politically incorrect, but he fails to persuade any but the already-fervently-converted precisely because he has nothing to offer beyond his vitriol.
On the other hand Ruddiman, a respected scientist, critiques a widely-held hypothesis about human contributions to climate change, but he does it by doing responsible, persuasive science. The point of my post is to contrast the two approaches.
I have absolutely no informed opinion of Ruddiman's theoy. From Molon's account it seems to have no direct bearing on the so-called debate about global warming.
Ruddiman's work significantly refines previous models for the causes of climate change, including the speed with which it has happened -- and therefore is likely to happen in the immediate future. Its direct bearing is two-fold.
First, it cautions that we should not be too quick to draw detailed conclusions about the benefits of policy decisions on the climate - either decisions to try to slow warming or the implicit decision to do nothing - based on older models. They are demonstrably inadequate insofar as they appear to leave out significant forces cooling the earth and also significant human-caused warming prior to the recent past.
And second, by refining the previous models, it offers a way to make better predictions about climate trends and the potential impact of policy proposals. If you read the 2003 paper I linked, you'll see that Ruddiman provides detailed calculations from which he drew his conclusions. Those calculations and the data they apply to are being examined right now and in many cases supporting and refining data are being integrated. Better science means better input into global warming policy decisions -- if it is recognized and heard.
Mark's comments #14 & 15 actually clinch the religious nature of his response. Let's start with:
Translation:
Then there's:
Translation:
No, can't understand why anyone might describe this as "religious...."
Molon,
I very much appreciate your latest post as it does indeed help to clear up some misunderstandings on my part. However, only to a certain point.
Let me go back and repeat something I wrote earlier. By contrasting the positions of Ruddiman with Fumento, you are confusing science with advocacy. By confusing, I don't mean to imply that you are confused, only that your argument confuses as a kind of rhetorical trick.
My very limited understanding of Ruddiman's work is based entitely upon your synopsis. That said, it is hard to understand from your synopsis how information regarding the speed with with pre-industrial agricultural practices affected climate change could have much impact upon our knowledge of the speed with which post-industrial industrial practices might affect climate change since the two practices in questions have little in common other than they are man-made, or for those who prefer their words all greeked up, anthropogenic.
You write that Ruddiman's work "cautions that we should not be too quick to draw detailed conclusions about the benefits of policy decisions on the climate -- either decisions to try to slow warming or the implicit decision to do nothing"
okay. how do we act upon this caution since we can't a) do nothing or b) take action? What's option c? Wait? Wait for more detailed information to draw more detailed conclusions. Isn't that "doing nothing?" But how long do we wait? Till we know absolutely everything there is to know?
Finally, your remarks about Al Gore only serve to further my belief that you do actually feel a need to debunk him and that a pre-existing political stance determines your choice of which scientists to listen to and which scientists to dismiss. As I said in an earlier post, I believe you are conclusion shopping, looking for the right one to suit your needs.
I hope I am wrong.
We can do several things.
The scientists can go back and review their research and data in light of Ruddiman's analysis and see where his new insights make a difference in their predictions. Note that his analysis is NOT limited to the human contribution via agriculture. He ALSO modifies erroneous models of the natural cooling cycle the earth is in.
They are doing that right now, in increasing numbers.
The policy influencers can publicly admit that there is a lot more uncertainty about the trends than has been suggested by various media accounts about global warming.
We all can re-frame the policy discussion (about what to do right now) around the theme of uncertainty and risk management. AL nails it when he says that, while he has reservations regarding many claims about human impact on the climate, he also thinks it's prudent to act AS IF those claims are true, until such time as the science allows us to calibrate our actions better.
I agree, with this caveat: stressing our uncertainty should bring humility to our policy decisions too. That is, I am strongly in favor of incremental policy actions that appear to have a lot of "bang for the buck" because that's like buying insurance. If we turn out to need it, we'll need it badly and it will be too late to put it in place.
On the other hand, I am leery of putting into place hugely bureaucratic mechanisms that are open to political and economic gaming, at this point. We've seen the massive failures and corruption at UN agencies. Kyoto as written was (in my opinion and in the opinion of many Europeans I've talked with) an attempt by the EU to make itself more economically competitive by manipulating the ground rules for international trade ... as WELL AS being at least in part a sincere concern for future climate conditions.
But that is exactly the sort of thing we should be debating: how much risk to take vs. how much cost to incur in the face of uncertainty.
I have a question I've never seen anyone actually tackle, I'm wondering if anyone else here has bumped into this...and that is:
What, exactly, is wrong with global warming that it must be prevented at all costs?
Usually I just hear bad stuff about what it will do to humanity (rising sea levels, disrupted agriculture, etc). In that case, I'd think you'd just want to add up the economic cost of prevention and compare it to the economic cost of treatment and see which is lower?
However, what I can't seem to find is an analysis of the effects on the non-human ecosystem. I would think that the effect (except for a few very cold adapted species) would be a positive: more warm, shallow, continental shelf ocean area in particular. Striking is that fact that the planet has tended to be warmer than it currently is during most of the phases of history where lot's of new species showed up, just by my unscientific scan the timeline survey. I'd love to read a professional take on the subject.
I think us primates can take care of ourselves just fine if the planet warms up a nice, say 5 degrees C. I'm curious about the rest of the planet: good? bad? just different? Anyone actually looking at this seriously out there?
Treefrog, if no one else answers that question, I'll take a stab at finding relevant literature on it. But anyone else with expertise in this area, please chime in!!
For those interested, the Sturm paper which gives credence to Ruddiman's analysis is, I believe, this one. It's available online but not for free, I'm afraid; however the abstract and the papers that have already cited it may be of interest to those who don't have a university or lab license to get at the whole text of the article.
The article reinforces Ruddiman's analysis because it verifies the impact of vegetation changes in warming the atmosphere. And Treefrog, the following paper from 2006 which cites Sturm's 2005 paper may be relevant to your question:
treefrog - good question.
Indeed, the weight of the "goodness" vs the "badness" of a warmer planet ought to be an input into policy decisions.
Occasionally I check out http://www.realclimate.org/ to see if anything interesting is there... and on occasion they report on the output of models showing temperature changes and precipitation changes.
I believe your question is simply to complex to answer with simple ups and downs. Rather, probabilities could be assigned to possible outcomes. But even that will likely leave you dissatisfied.
Thus the problem of policy. Whatever the state of the science of climate change, policies will be implemented. Thus decisions are being made, and will continue to be made, from ignorance.
In light of this, prudence would dictate a conservative approach, to protect the current state of the climate if at all possible, or as close to it as we can do. To proactively seek change without knowing the outcome is akin to gambling.
Joe,
I've heard of straw men before, but never before seen anyone go to such extremes to build one.
There's nothing "religious" about pointing out the political bias behind Molon's choice of theories to offer us. Now, if I had attacked Ruddiman's work itself because of Molon's choice, you might have a case--and your attack against me for admitting my ignorance of Ruddiman's work might have had a little teeth--but I didn't.
Molon slipped in a number of comments that make me suspect he's out shopping for that just right little scientific conclusion that will go well with the rest of his wardrobe. I thought it worth pointing that out because it has become a common trick. "Let's wait and see till ALL the facts are in before we make a conclusion since I don't like this conclusion." To me this is the wrong approach.
I grant you that it has no bearing on the merits of any one particular theory. But then I never said it did. You just said that I said it did. & that just ain't true, Joe. So try again.
This approach does, however, have a cumulative detrimental effect. Intellegent Design is not a bad theory BECAUSE people who advance it are politically motivated. It is a bad theory all on its own. (&, again, Joe, please listen carefully here: I'm nost saying Ruddiman's is or is not a bad theory.) But it is fair to point out when you suspect someone is looking for a particular conclusion as that is an intellectually delplorable habit to get into. And let's remember, we are talking about Molon here, not Ruddiman. Molon, I believe, is conclusion shoping. Not Ruddiman.
I mistrust Molon's claim that he has chosen Ruddiman to advance because Ruddiman's work is "objective." I think Molon likes the conclusions. And, AS A GENERAL RULE, that's not a good reason for chosing among competing theories.
If that is too religious a stance for you, then may God bless you and have mercy upon your soul.
Oh, mark, you really really do not want to read and respond to what I've actually written, do you?
You think I'm conclusion shopping, but do not acknowledge that I deliberately linked to a discussion of Ruddiman's thesis on a site that tends to promote the earlier hypothesis.
You continue to argue from your impressions of motives that you think might lie behind my post, without once acknowledging the range of data I present or my repeated insistence that I am interested in good science, not a pre-determined conclusion.
If that's not a (metaphorically) 'religious' belief, I'm hard put to know what is.
And the deep irony here is that Ruddiman's work, while it challenges aspects of the previous models (and hence conclusions drawn from them) does NOT encourage us to laugh off the potential problems with warming trends happening today. It DOES, however, raise some questions that should be considered by scientists and policymakers alike. If raising those questions, based on solid data and analysys, is troublesome to you, then that's another sign that you are coming from an emotional commitment of your own and not from an open mind based on science.
And for what it's worth, I'm not an Intelligent Design kind of person. Speaking of strawmen!!
mark #18 wrote:
mark, I think you bring up an excellent point; I will attempt to argue the opposite. Many years ago, I took an upper level undergrad class in "Systems Dynamics" with Prof. Dennis Meadows, co-author of the influential 1972 Limits to Growth.
Systems Dynamics was an early and influential attempt to use computers to model complex systems. The language in use at the time (late '70s) was DYNAMO. The process we used was the same as that employed for the "Limits" Club of Rome study, and it was driven by the same philosophy that undergirds the exponentially more complex global climate models used today.
To model a system (from memory, I'm probably skipping steps):
DYNAMO, like modern languages used to model GCMs today, is iterative. You set up equations, reservoir numbers, and starting conditions, then let the model roll forward, one calculation per time period (in this case, 1x/year).
You can see where this is going. For 2007 GCMs as well as for seventies DYNAMO fisheries, a "valid" model has to be able to "forecast" the historical record. In practice, the model gets to its current state by being tweaked in hundreds (fisheries) or thousands (GCM) of ways. But if unknown things were having large effects on the past record, then obviously the modeler did not include them in the model.
So in that case, you have a model that is better than the concepts that it is built on! But that's impossible...
How will the faults of such a model translate into its ability to predict future trends and events? That is, after all, the point of the exercise. These sorts of systematic errors might be very small, or large. In terms of using the model to make policy decisions--how do you know which?
This is why it's crucially important to get the relevant data from the past right. Raw data, in terms of temperatures, atmospheric C02, orbital precession, solar intensity, cloud cover... If there is an important factor that had a strong influence on a critical variable, as Ruddiman is saying, do the current GCMs already have this built-in, directly or indirectly? What does it mean if a model's retrospective 'predictions' conform beautifully to historical data even in the absence of critical moving pieces?
This is a feature of GCMs that, as a climatological ignoramus, I find worrisome. Given the way they are built and revised, if they had little predictive value, how would you know that they had little predictive value?
...now I will post without benefit of Preview and hope for the best...
AMac, systems dynamics modeling is alive and well, but as you note its use in many cases is hit or miss unless the relevant feedback loops are correctly defined and characterized mathematically.
In the case of modeling the various factors that affect climate change (hotter or colder), Ruddiman has pointed out specific ways in which the previous models did not correctly "predict" (i.e. account for) the undisputed data. That factor wasn't built into global climate models for future climate change because previously climatologists were assuming (in many cases) that the anomalies were due to non-repeating causes. Ruddiman argues that the mechanisms they were assuming couldn't produce those measured data and he proposes an alternative mechanism which he grounds in both the old data and newer data (such as information on the extent and rate of deforestation at various times).
His resulting model seems to fit all the data we currently have better than the previous model and on that basis I would say it's better. Lovett and others read Sturm's paper (published after Ruddiman's 2003 talk and paper) as subsequently validating one key assertion in Ruddiman's hypothesis. That too lends confidence in his model.
But that doesn't mean it's the last word on the topic. It can and should be examined critically and compared against new data that emerges.
Lest I be charged as an anti-warm-monger, here is a comment on global warming from 2002. I think this overall perspective is consistent with what Molon Labe has written here, and is not "conclusion shopping."
Molon,
As I said, I could very well be entirely wrong in my belief about you. I have been very upfront that my impressions--as you rightly call them--are based only upon what you have written in this thread.
I am skeptical by nature. I've had very little experience on/of this site. Such as it has been, however, has led me to suspect "conclusion-shopping" around every corner. Perhaps my skepticism has grown toward paranoia in this regard. I am willing to be wrong and to stand corrected.
Fair enough!
Indeed, fair enough. For instance, I, myself am suspicious ranging toward paranoia when it comes to folks who object to scientific work without reading it or performing other examinations toward credibility. But such paranoia is not always justified.
I'll add that I was just at the NAMM music industry conference, and having a chat with a Scot and an Englishman, both in their 50s. The Scot was talking about how if he was 10 these days he'd slit his wrists, what with global warming and all.
To which I replied:
"Now I've heard everything. A Scot is telling me that large parts of England will be underwater soon, and the Highlands will be warmer in the bargain, and this DEPRESSES him?"
Molon
Thanks, that's the kind of data and questions I'd like to see being gathered/asked, and that no one really seems to be asking.
My current read on it, based on what little I've found so far, is that the most likely global warming scenario is that current cold zones will heat up, displacing species adapted to them with ones that are more competitive in warmer zones. Long term, we're likely to see more speciation to take advantage of the new striations of the climate map.
I'm having trouble seeing the point of the panic button here, if life were that fragile I don't think we'd be here now.
Even the worse alarmist aren't suggesting we're going to be boiling the oceans anytime soon. And if it is man-made in nature, well, that's actually kind of reassuring in a way, as that means it can be man-unmade by one method or another. (If it's natural on the other hand...)
Freeto
I understand the point of being conservative on these things. But if you/we/us/whoever is going to ask the world to spend countless billions of dollars to attempt to solve a problem without being sure of what's causing it, if the 'solution' will even affect it, and even if it actually IS a problem...it's going to be kind of a tough sell. Which is probably why nobody is actually doing anything about it.
It's like someone decided 1969 was the year the universe hit perfection and any changes from that are downhill.
Here's the question (and follow ups) I want to see answered...
Is there an optimal temperature (or range of) for the planet?
If so, what is it and why?
If not, why do global temperature variations (natural or manmade) matter? Is it the rate of change, or the change itself that is a problem?
I asked the first question to some guy who was giving a lecture and answering questions at an earth environmental display at the London Natural History Museum over the summer. Well, to be more precise, I asked 'Since global warming is a bad thing, that would imply we're moving away from an optimal temperature point, what is that point? 1950? 1850? 0? 10,000 BC? 100,000,000 BC?'
He didn't even begin to know how to answer. He'd obviously never even thought about it. Which is really sad, as am I way off base in assuming this ought to be the second question (behind is it actually happening)?
So far the only answer I ever get is the same as Freeto gave 'It's complex'.
My answer: So is putting a man on the moon. Is this, or is this not important? Why does no one seem to be working on this?
Joe,
we scots are hard to please. in fact, we don't much care for being pleased at all.
Treefrog, an initial search through some citation databases identified these as books and articles you might want to read:
Biogeochemistry : An Analysis of Global Change by Schlesinger. 1999, heavily cited, available in paperback. Very influential, used as a text in many courses but might take some long careful reading to be useful to you. I haven't read it so I'm not sure ...
The article Ecological Consequences of Recent Climate Change is available online from the British Library. Cited heavily, 2001.
Even more heavily cited is the 2002 article Ecological Responses to Recent Climate Change .
The 1999 article The ecological consequences of changes in biodiversity: a search for general principles" lays out, as the title suggests, some general principles for thinking about the impact of ecological changes brought about by changes in the climate. Again, a very heavily cited article available for purchase from the BL.
The article Assessing effects of forecasted climate change on the diversity and distribution of European higher plants for 2050 can be purchased electronically from the British Library and addresses a different area of the ecosystem than the arctic/marine biology of paper I cited earlier.
The 1999 article Effects of climate change on biodiversity: a review and identification of key research issues is also available from the BL and can give you authors, key words and a sense of the issues that you can then do more searches on.
Hope this helps. The issues you've raise are being addressed, but sometimes it's in fragmented bits of scholarship rather than high-level overviews. But in and among those studies are broader analyses such as the ones I've listed here. (But I gather the book is pretty detailed and technical.) If you purchase and read any of these, I hope you'll come back and do a guest post or a comment with your take on them.
Molon Labe: Very well written piece. There was nothing confusing about it, but I read the printed words and not all of the secret inferences in the spaces between.
TreeFrog Question (#20): I am generaly of like mind about weighing costs and benefits, which is a problem in the global warming debate where there are uncertain risks of potentially, albeit possibly remote, catastrophe. But your specific question about the relative winners and losers of global warming is not particularly helpful to me unless someone is prepared to answer this question first:
If the polar bear wins and the horned toad loses, who decides? If Canada wins and the U.S. loses, who decides? If the coastal areas lose and the interior wins, who decides? The U.N.? A plebocide? A council of scientists? War?
PD: Cynically and pragmatically, unless someone is willing to take it to war, the answer will be decided by China and India, and their pace of development and energy consumption. The developed nations' energy usage per head and unit of economic output has been trending downward for some time, and IIRC (too late and lazy to chase link) it has also turned downward on an absolute scale.
The only 'someone' with the resources to apply coercion of the required magnitude to change the development trajectory of the LDCs is the US. We are otherwise occupied, and I have yet to detect one scintilla of evidence that even the most enthusiastic followers of the millenarian view of warming have an intent in that direction.
The fate of the polar bears and the horny toads will be decided in Beijing and Delhi. Get used to it.
Not to say that we shouldn't be making efforts unilaterally, for many reasons. (Greater) energy independence has a merit all its own, as does ceasing to fund our enemies. As a techie, I see wisdom in the notions of buying our way out the learning curves on (solar, hybrid...) as a competitive measure and as an end of its own. So much the better if these goals evoke common cause with those whose rationales are more, um, religious - I can't say I'm devoid of that motivation myself, and common causes have been thin on the ground lately.
But we're going to have to get over the notion that warming is going to happen or not based on our actions. We'd better start figuring out how we're going to adapt, and perhaps help the biosphere adapt, and that requires exactly the kind of critical modeling being discussed here.
(And Mark, re the Scots: Be as grumpy as you like, just keep making that whiskey...)
Joe,
Watcha doin' at NAMM? I don't suppose Defense Industry Daily sent you!
And regarding the Scottish outlook: haven't you heard the explanation of golf that goes, "The Scots believe that man was meant to suffer, and never more than when he set out to have fun"???
I highly recommend "The Skeptical Environmentalist" by Bjorn Lomborg to help understand the global warming discussion. There seems to be an abnormal amount of politics and hype injected into this topic.
Amazon.com link
The book is a well-vetted and easy-to-understand analysis of environmental topics, drawing conclusions by referencing numerous studies. It repudiates most of "the sky is falling" concerns.
If global warming turns out to be good for anything, then it was surely invented by the Scots-Irish, and there's bugger-all you can do to stop it.
Kirk, I've noted before that defense and the music industry sometimes go together:
Still, that isn't what I was there for. I was accompanying my wife, and wearing an employee badge from the company she works for. Deserved one, too, but that's another story. Interesting experience, anyway. Thought about taking a day to stroll around Disneyland while I was there, but would rather do it when she can come too.
Our Scottish and Welsh/British friend were both company employees as well, from the European group. They both laughed, and observed that I must have been paying attention in the bars.
Current thinking is that solar output has been a significant if not the major input to the current episode of global warming.
Scientist have measured global warming on Mars and another planet (Neptune I think).
Does Ruddiman account for solar variability?
A Geologist Looks At Global Warming
Which links to a site with NASA charts.
The earth has been much hotter. More CO2.
In addition it was warmer when ocean circulation was freeer. i.e. one continent.
Models with chunks 150 miles on a side do not do transport equations or mountains well.
We have no certainty if water vapor feedback is positive, negative, or neutral. Water vapor is probably the most significant greenhouse gas.
A model not derrived from fundamental factors but is tweaked so that the model matches history has limited predictive value. Suppose the wrong equations were tweaked? Suppose the equations are wrong.
The fact that models require so much tweaking says that climate is complex. Models are poor. Also with such big chunks the models are very subject to initial conditions. i.e. starting the model in 1860 vs 1861 makes a significant difference. If the model was good it wouldn't matter which year you chose for initial conditions.
The right filters can turn white noise into a symphony.
GIGO.
Did I mention that we do not have a significant amount of good data to work with?
Temperatures of air, water, upper atmosphere etc. Air circulation patterns. Jet streams. Ocean currents. etc.
Since the models are sensitive to initial conditions bad data or missing data (fill in the blanks) is a killer.
LGILGO - L = lots
And it won't be billions spent it will be 10s of trillions.
And the best question (already asked) is: what is the optimum climate? Do we optimize for polar bears or plant growth?
mark must be postmodernist. He is most comfortable considering motivations and relationships then he is actually understanding logic, facts, and science of an argument.
You see, logic, facts, and science are only social constructs and tools of patriarchal suppressors. mark only needs to understand your politics so he can figure out if you're "correct" or not. Your argument doesn't matter.
For #42 "And the best question (already asked) is: what is the optimum climate?" --- I think it is not that simple.
The problem for us, modern humans, isn't just what is "optimum" (whatever that is decided to be...), but how fast and through what methods will we get there?
Let's say Earth, as a life bearing system, is better (e.g., more living things) when the Earth is 5C warmer than it was in 1920. But if the changes happen in only a few decades, the side effects (raises in sea level and food supply shortages) will be disasters leading to mass human deaths.
It is a tough sell to any electorate, to ask them to think about someone else on another part of the globe. Perhaps it is too much to ask. So activists/alarmists try to come up with scenarios that will hit home. E.g., if the sea rises 1 more meter then New Orleans really should be abandoned. However, if simultaneously grain product increases in the upper Midwest, was that 1 meter rise worth it?
These are only hypothetical questions - I do not believe we who are living in a modern high energy-use society will be able to give up our lifestyle through our own choice. Nor do I believe the 2.5 billion people in China and India will give up their quest for a better life. Thus, investment opportunities in Coal (and associated rail companies) exist and are recommended.
Here is my challenge to the W.o.C. community : find alternative paths (policies, theories, talking points, and actual implementations) to deal with energy and climate problems, that will be reasonable and winning against the extremist/marxist/statist positions that opportunists are taking. Currently the web is dominated by extreme leftists and nihilists in these matters, and I am hoping that liberty-minded folk will band together to bring common sense into the discussion.
M. Simon asks:
Does Ruddiman account for solar variability?
Yes. It's central in his analysis. The glaciation that would have happened were it not for the unintended side-effects of agriculture is predicted precisely as a consequence of the 3 cycles of variation that affect how much solar radiation reaches the earth. Those cycles are: variability in the tilt of the earth on its axis, precession and variability in the elliptical orbit of the earth. The last glaciation melted due to those 3 factors being at a temporary high; however, what would have followed is predicted to have been another glaciation in a couple thousand years (a continuation of the cooler period the earth would have been in), were it not for the carbon dioxide and metthane released by human agriculture, coupled with deforestation.
ET #17, Lomborg's book is reportedly well-written. He is not, however, a climatologist. His PhD is in political science. Relying on him to trace political issues associated with the climate makes sense. Relying on him to critique scientific research is a lot more iffy IMO.
Challenge met and answered:
Easy Low Cost No Radiation Fusion
#45,
Those are the corrections I would expect. What I'm talking about is the fact that the sun is a variable star whose output fluctuates in UNKNOWN cycles of UNKNOWN magnitude.
Maunder Minimum type stuff which lead to the Little Ice Age.
Lomborg does statistics and other math very well.
Lomborg does do stats well. What he doesn't bring is expertise in which stats are predictive, and where the limitations are in data collection and interpretation.
I'd invite you to read Ruddiman for yourself and report back on the answers to your questions. There's a link in my comment #13 above to many of his most influential articles, so there's lots of info for you to track down if you're interested. I also plan to review his latest book once it arrives, as well.
> 1. the earth has warmed over the last 100 years.
> 2. the warming has accelerated over the last 13 years.
> 3. burning of fossil fuel contributes to both 1 & 2.
> There's nothing murky about that.
> After that comes all the advocates and politics.
Not so fast. That list is missing so many facts that it's useless.
For example,
(1) How much of 2 is due to 3?
(2) What is the effect of 2?
(3) What are the plausible consequences of 1? (It's not unprecedented - I'd like to see greenland green.)
mark,
I hope your objections have been addressed.
It seemed to me rather strange that someone who would ACCEPT the argument that
global warming can be linked to greenhouse gases released by increasingly greater amounts of human-originated INDUSTRIAL activities over an extended time period
would REJECT the argument that
global warming can be linked to greenhouse gases released by increasingly greater amounts of human-originated NONINDUSTRIAL activities over an extended time period
WITHOUT first reviewing the analysis and the data.
Perhaps :-) it's a Scottish thing?
bfartan, luker,
I NEVER rejected the arguments. Do you guys actually read the posts?
None of my posts had anything to do with the merits of Ruddiman's theories--or even with the relative merits of any of the thousands of theories about global warming.
My posts were merely questioning the motives behind Molon's choice of theories to advocate. My questions were based on some of the words and phrases he used in his presentation. I suspected he favored the conclusion. He's says not. I accept that. I'm not a mind-reader so I'll trust him. But, sheesh, is it a crime around here to suspect someone is looking at the politics rather than the science of the issue? Apparently, it is.
I explicitly stated that Molon's motives had no bearing on the merits of Ruddiman's theories. But apparently you two chose to skip over that, I guess because your posts wouldn't have been as much fun to write.
Andy Freeman,
I cannot believe you did that. In your quote of an ealier post of mine you took out a sizable piece of it and then tried to make the very point the missing piece addressed.
Not only that, you left in a portion that referred to the missing piece and tried to make it look as if I had been referring to something else.
That is low, man. Very, very, very low.
Here's what you conveniently removed.
"Predictions about the future are murkier and there is less agreement among scientists about what might or might not happen, the range of possibilities and the liklihood of occurence."
I then went on to say "After THAT", the THAT referring to the above, comes the advocacy and politics.
You then make the very points that were made in the portion you removed.
Wouldn't it have been easier to just have said, "I agree with mark?"
One other question: do you sleep well?
mark,
It is you that do not understand. Everyone may or may not have motives for advancing particular arguments. Being human, we all have our motives. The arguments should stand or fall on their own merits. Motive is not a factor except for postmodern deconstruction, which makes it the overriding target of any analysis.
If you do not wish to be lumped with deconstructionist ducks, might I suggest that you cease quacking?
But, sheesh, is it a crime around here to suspect someone is looking at the politics rather than the science of the issue?
It's not a crime, but if you want to be taken seriously your assertions should match the visible evidence to the contrary, including:
(1) a link to a major site on which arguments for the prior model are made extensively
(2) repeated statements, backed by specific quotes, that make it very clear that Ruddiman's work does not suggest we become complacent about climate change linked to human activity -- quite the opposite
(3) links to Ruddiman's work available for free, so that you can judge it yourself (I'm not looking for converts, just reporting research activity)
(4) links to influential papers regarding the effect of climate change on our ecologies, not one of which appears to debunk or downplay the impact of global warming -- quite the opposite
Not ONE of these offers a politicized rejection of the importance of climate change linked to human activity. Not one. And yet you repeatedly refuse to engage all that material I've posted, preferring again and again to worry that I might be anti-Gore.
You know, I can put reasoned argument out there, backed up by extensive links to quality data and analyses worthy of being taken seriously. But if you don't read it, or don't read and acknowledge the overwhelming thrust of what I personally write, well .....
it's not a crime, but it does make you less than persuasive, to put it mildly.
Persuasive commenters go beyond having suspicions -- they actually investigate whether or not those suspicions are well-founded. Just as persuasive science begins with an hypothesis, and then collects and objectively analyzes data to see if it support s or disproves that hypothesis.
luker,
I disagree. I disagree strongly. People in this country--and presumably in other countries, as well--too often pick the conclusion they want and then go search for the science that will support it.
As I said earlier, I think that's a bad habit to get into. I think the reasons are obvious. You end up with Intellegent Design theories being taught in science classes, e.g.
I do agree with you--and have said many times--that the merits of any particular theory can not be judged by the motives of any one supporter.
But if you cannot separate the two issues in your mind and see the clear distinctions, we probably don't need to talk about this anymore.
Generalizations, mark. All you offer are unsupported generalizations.
They are unpersuasive, repetitive and at this point boring.
mark,
I hope you wrote #56 before reading #55 (the timestamps suggest as much).
Molon,
I do not disupte Ruddiman's work. Let me say that again: I do not disupte Ruddiman's work. I have never claimed it was politically biased or based. Can I be any more clear about that?
All I ever said was that based on your use of terms like "politically correct theories" and YOUR mention of Al Gore, that it seemed to me that you, you Molon, were promoting Ruddiman's work because his conclusions were useful to your previously-held beliefs. You have said that is not true. I have said I accept that.
Motivations and biases are irrelevant unless you can show that the argument is biased and irrelevant. You problem is that you engaged the biases and motivations first and continue to do so, without any care about the actual case presented.
If Molon Labe were to stipulate that he hates Al Gore and wished to see him converted into organic fertilizer (not that he does and not that he wishes), what would have been you gain for having engaged him and extracted such concessions?
The factual case stands on it's own. So, it's not affected logically, except that the deconstructionist would believe it to carry less or zero weight because of it's advocates demonstrated motivations.
Again, quacking like a duck.
You're missing the point, mark.
Your assertion ABOUT ME was off base, demonstrably so based on visible evidence. You don't need my claim on that -- read what I actually wrote to see it, if you're willing to actually engage the evidence here on the site.
THAT is what makes you unpersuasive and at this point boring. You insist on making this an issue of opinion and counter-claim, without acknowledging the evidence in front of you that your first impression was very likely to have been, upon reflection, wrong.
Molon,
Well, we know seem to have moved from the issue of whether or not you were "conclusion shopping" -- and I respectfully accept your claim that you were not...
to the new issue of whether or not "conclusion shopping" is an acceptable way of approaching science.
Everyone but me seems to think it's fine, that it's simply human and that we should never look into the motives of why someone would support one theory over a competing theory.
Nope. You're not getting it.
Conclusion-shopping is irrelevant, if everyone focuses on critical examination of data and how that data was analyzed.
If someone is conclusion-shopping, those conclusions will soon enough be brought under the microscope of good science, where they either stand or fall on their merits.
But that process depends on a willingness to actually examine data and chains of reasoning with objective care -- an activity you seem not to be very experienced in or willing to attempt, at least here in this discussion thread.
By the way, it may (or may not) be relevant at this point to say that my own area of research expertise is cognitive and information science.
In other words, I know a fair amount about how people form concepts, come to hold opinions and validate opinions (or not) in the face of evidence. I could in fact link to reams of research literature on the topic.
It's not news to me that people often pretend to be examining theories when in fact they are seeking to justify already-held beliefs. We could, on another thread, look at the neuroscience that explains how and why that happens, why the brain is wired that way and how that does or doesn't suggest strategies for the design of e.g. artificial intelligence software -- or educational curricula.
But the point here is that you have amply evidence in front of you that suggests I was not and am not conclusion shopping with regard to climate issues. And you repeatedly fail to recognize and acknowledge that evidence.
THAT looks a lot like "conclusion shopping" on YOUR part.
You're not alone in this. There's a whole lot of evidence-blindness on both sides of the global warming issue. Those who simplistically reduce the issue to catastophe brought on by SUVs etc. do it. So do the people who point triumphantly to a cold snap in this or that location as proof that warming isn't happening (when the thermodynamics of fluid systems actually predicts weather extremes of hot AND cold as a result of warming, as temperatures try to equalize across the atmosphere as a whole).
So what can we do to avoid this sort of blindness? We can do what Ruddiman does -- gather all the data, analyze it as objectively as possible, look for analyses that account for all the data and make follow-on hypotheses that can be tested for more insight.
lurker,
your argument would make sense if I were making the claims you say I am making. If I were trying to discredit or contradict Ruddiman's theory by questioning the motives of a 3rd party who referred to it, you would have a point...a good point. But since I wasn't, you don't.
Look lurker, if you think it's okay to reach a conclusion first and then go look for the data to support the conclusion, well, bon voyage, my friend. Go & live in peace.
Molon,
Ruddiman talks about solar forcing which I assume he means various orbital factors and precession. Those are the solar cycles he mentions. They have been well understood for some time.
Zero about the Maunder minimum. Zero about the sun as a variable star.
For instance a paper that was to be relesed in Feb (haven't checked to see if it has been released) shows the solar output to have increased .5% over the last 100 years. That is a pretty significant increase.
The sun as a variable star is well known. At least since the correlation of sun spots with the Little Ice Age was found. What is not known (very well) is how that affects solar output. And what the cycle periods are. We know of the 11/22 year period but larger oscillations (including the Maunder minimum) are not well understood.
If you don't understand solar output cycles then any attempt to calculate anything is useless except as a way to get government grants.
BTW I have never heard of any climate models (I am only a dabbler in the field so I could be in error) that even take into account the known current 11/22 year sunspot cycle - whose period fluctuates some.
I'm disputing Ruddiman's work.
Excellent discussion, mature tones and intelligent exchanges. How can this be happening on the Internet?
My thoughts on the issue are based on my engineering operational experience which warns me that any 'control mechanism' (control global temperatures via modulation of atmospheric composition) with a century-scale feed-back loop (we won't even get indications the technique is working or not for decades, and take decades more to develop technique alterations before implementation begins, and decades more to shift political decisions) is a classic "unstable" system, like trying to drive a car down the road with a one-minute time lag in all control inputs.
A better approach would add more short-term modulation techniques, and the control point is atmospheric opacity -- where we are already making massive inputs via cleaner air from large-scale anti-pollution actions. No, don't re-instate smog -- but find other ways to enhance planetary albedo -- from artificially building up cloud cover 1 to 2%, to the dreams of space-based reflectors, to other technological approaches that can be prototyped, implemented, observed in action, and modified within a period of years, not decades (or even centuries).
Such a response time is also better adapted to natural events such as volcanism or external variabilities, and mechanisms can be adjusted to accommodate them.
I see the objections to this approach as primarily 'pseudo-religious' -- the faith that without ANY human interference Earth's climate would naturally seek a benign balance -- and political, where the advocated solution -- massive de-industrialization and centralized economic control -- had already been on the agenda of groups who now have just found a NEW excuse for their old, favorite policy recommendations.
My $0.02, in respect...
jameseoberg@houston.rr.com
www.jamesoberg.com
I just checked. When Ruddiman says solar forcing he means orbital and other similar mechanical effects.
He says nothing about the sun as a variable star.
BIG HOLE
Another interesting 'solar forcing' factor is solar magnetic field strength and its role in fending off galactic cosmic rays whose varying flux in the atmosphere creates different levels of ionization, which in turn lead to varying levels of condensation nuclei for raindrop (and hence high-altitude cloud) formation.
In general, 'solar forcing' refers to any impact of solar radiation on the levels of greenhouse gasses in the atmosphere.
But if you're right, M. Simon, I rather expect climatologists to point that out in their critiques. Whether that omission -- if it IS an omission -- in Ruddiman's model matters much is an important question but not one you've answered at all. So your assertion that this is a BIG HOLE is just an assertion and little more.
The effects of sunspot activity aren't a secret but neither are they well-modeled in terms of their potential impact on climate. But again, just quoting numbers isn't enough.
For instance, you assert that an increase in solar radiation of .5% over a century is large amount. What matters, however, is how much of that increased radiation is transferred to the atmosphere in the form of heat. I don't have an answer to that, but look at the first paper whose abstract I quoted in #20 above. That 2005 paper establishes that vegetation coverage has a significant influence on how much sunshine gets reflected back into space vs. how much gets absorbed as heat. But the type and extent of vegetative cover in some region is a function of many factors, including human activity and the current climate at a given time. There are complex feedback loops involved here. Just quoting .5% doesn't tell us very much.
This illustrates why it can be very misleading to go cherrypicking facts/assertions without grounding in the science in question. I'm not a climatologist and neither are you. Ruddiman, on the other hand, is one of the top paleoclimatologists in his field with over 50 years of highly regarded research and analysis of long term climate mechanisms. He may have missed something, but I'm pretty sure it won't be something you or I can just look at and say "AHA! There's a BIG HOLE in his theory."
Sometimes a little humility is called for on our part. ;-)
Excuse me, that paper abstract is quoted in #21 above, not #20.
Ruddiman does mention Milankovitch cycles which are functions of orbital mechanics and earth wobble.
#70 Jim O.,
Thanks! I had forgotten that one.
BTW water vapor is the #1 greenhouse gas. No one is certain (within the error limits of the data or models) whether its feedback to the system is positive, negative, or neutral. Let alone the magnitude.
How is prediction possible?
The climate modelers have that one covered. They assume positive feed back adjust the factor to some "reasonable" factor and then assume that added CO2 will have its effect multiplied by positive water vapor feedback.
Piling up the assumptions are we?
Yes, there are a lot of assumptions in climate models, if I understand correctly.
That's why work like Ruddiman's, which analyzes data and proposes mechanisms and rates of change that better fit all known data, is so valuable. By highlighting the role of vegetation cover as part of the atmospheric warming mechanism, he has triggered a lot of new data gathering and mechanism investigation.
You really ought to see, M. Simon, that he appears to share your and my dislike of facile assumptions.
M. Simon, if I understand the Ruddiman study correctly, you are not disputing his finding that CO2 and CH4 increases are 5,000 / 8,000 year trends. Am I correct? You appear to be disputing his profered explanation of man-made agricultural activities as being the explanation, given that he appears to have ignored a significant variable (solar cycles). But would solar variability explain his first finding, an "anomalous increase" in CO2 8000 years ago and CH4 5000 years ago? Do those time periods have any significance to solar phenomena?
mark, how many times do you have to get your ass kicked before you figure out that you're not Bruce Lee?
Molon,
You and I are in agreement:
The effects of sunspot activity aren't a secret but neither are they well-modeled in terms of their potential impact on climate. But again, just quoting numbers isn't enough.
The trouble here is that we have about 500 or 1,000 years of semi-reliable sunspot data.
And yes the biological feed backs are uncertain.
The error range as I understand it for climate models is larger that the known "normal" fluctuations. The climate modelers have that figured out. They do multiple runs and "average" them. Now if you are filtering signal from noise averaging the data does improve the signal to noise by 1/sqrt n (where n is the number of samples) where the noise is gaussian. However, doing that with a model is smoke an mirrors.
Then there is the noise in the input data.
Then all the unknowns. All the factors fudged to make the numbers come out "right". You might as well be doing psychology with a sledge hammer.
We do not know enough about climate to be betting anything but small amounts into further research. And much faster computers with a lot more memory.
The models are uncertain.
The data series is uncertain.
The computers are too small.
Did I mention that the recent historical record tends to show an increase in atmospheric CO2 after a warming trend starts? And if we go back far enough we see that CO2 may not be correlated with global temperatures at all.
"Climate science" is witchcraft with numbers. Not a bad thing. It will get better. At this point in time however, it is not very good.
Climate effects of CO2
CO2 Science
CO2 in Geologic Time
#75 from PD Shaw,
Good question PD. The answer is that variations in solar activity can't be ruled out because we don't know.
Did I mention that the recent historical record tends to show an increase in atmospheric CO2 after a warming trend starts? And if we go back far enough we see that CO2 may not be correlated with global temperatures at all.
M. Simon, I like your willingness to jump into topics for which you have no background and try to make sense of them. There comes a time when it's important to acknowledge the limitations of that approach, however.
The portion of your comment I've quoted above shows your unfamiliarity with how dynamic systems work and in particular with the way in which 2nd and 3rd order feedback loops behave in response to 1st order input changes. Simple correlation misses the point.
There is nothing mysterious or debunking about the fact that atmospheric CO2 might contingue to increase after a warming trend starts. What is open to investigation are the precise mechanisms and dampening factors that might be at work. It is precisely on this point that Ruddiman's hypothesis sheds light.
If you really want to dig into this on your own, it would help to have the right tools for analysis. I'm not, as I've said, a climatologist. I do however know something about model building, including models of dynamical systems in action.
AMac mentioned systems dynamics modelling, which is an attempt to apply the insights of control theory to systems like ecologies, human choices in urban settings etc. I have my concerns about some of the ways in which this has been applied to policy issues, but the underlying mathematics are sound and insightful.
A good place for any WOC reader to learn the basics about dynamical systems and feedback loops is one of the free online courses such as this one from MIT. You can use the Vensim PLE student sofware package, available free, to work through the exercises. They might seem elementary to you at first, but I encourage you to stick with it. If you do, you'll get a better intuitive understanding of dynamic systems that will allow you to see why the quote above is off-base.
Let us assume the models are perfect.
It ought to be possible then to go back 2,000 years and find some arbitrary but reasonable set of inputs at that point in model time that will give the climate for the 1900 to 1940.
No can do.
If you can't predict the past, how can any estimate by the models of the future be worth anything?
Nice of Ruddiman to have a shot at reducing the uncertainty in one small area of the models. The models are still of very low value.
You are confusing micro-prediction with macro trend identification and macro climate modeling. I'm sorry, M. Simon -- but you are really out of your depth on this issue.
That doesn't mean that I think existing models are perfect or even highly accurate. It does mean that I think you are taking potshots at them without understanding their nature or the basic disciplines associated with modeling complex systms, which is unpersuasive in the extreme as far as I'm concerned.
Molon,
You characterization of my understanding of models and systems is inadequate.
I'm considered an expert in servo system design including auto tuning (i.e. getting the system to find the value of its own "constants"). Real wold stuff. For which I got paid rather well (until I retired).
Second and third order effects are not unknown to me. Servoing chemical plants is a good example.
My job was to find every thing that could go wrong (within non-catastrophic limits) and design the system to maitain control within an error band. Murphy was my friend.
I must admit though that climate is much more difficult. Inputs are uncertain. Lag values unknown. Feedback unclear.
Fair enough.
But if that's true then you should know better than to talk as if CO2 should be directly and simply correlated with atmospheric temperature. Not to mention acknowledging that methane has a much higher impact on temperature than CO2.
You admit you aren't familiar enough with the specific control mechanisms or the climate data to say anything other than to express deep skepticsm about existing climate models. Yet you feel free to dismiss the careful and masterly work of someone who has demonstrated a significant expertise in those areas. You are eager to assert BIG HOLES that allegedly vitiate that work, without in fact having a basis for judging whether the allegedly omitted factor has a significant impact on the model's conclusions.
It's one thing to bring a skeptical mind to a topic. It's another thing to pass judgements based soley on your skepticism and unfamiliarity with a field.
OK we can do macro trend identification given enough data. I grant that.
That is useless.
Why? Because we have no idea (as in close to zero) of the cause.
In a chemical plant I can write the equations based on experimentally derrived reaction rates. Flows. Temperatures. Concentration of reactants. etc.
Not dissimilar to what a climate modeler does.
But no oil company is going to put a nickel into a plant design if I can't tell if the feedbacks in a certain reaction are positive, negative, or don't care. Not only that, I have to come within 10 to 20% of the real rate if the particular feed back is very significant. Because, the life or death of the company (profitability) demands that the design be done right.
Climate is not my main interest. However, there is enough similarity to my real world work to see the holes.
Water vapor is the most significant green house gas. What with clouds. Ice particles. etc. We do not understand the direction let alone the magnitude.
Solar output drive the whole system. We are ignorant of the variations over significant time periods.
From an engineering standpoint climate science is a joke.
Molon,
Climate modelers will admit that water vapor is A BIG HOLE.
Climate modelers will admit that inadequate computers are A BIG HOLE.
That ought to be enough for a start.
Solar output variability is an issue they don't even address. They can't; no one knows anything about it except the 11/22 year cycles. No one knows when the next Maunder Minimum is coming.
Is that enough macro stuff for you?
Thanks for the links, good stuff there. I have found some others, actually, just about any evolutionary study of the major ages includes a litle. They aren't intended and don't explicitly cover temperature changes, but environmental changes are one of the major causes of speciation, so any analysis of general evolution tends to touch on the topic indirectly.
I guess I'm with JimO, somebody decide what you want the temperature gauge to be at, and we'll figure out how to put it there.
From an engineering standpoint, when you have people pushing a pendulum too far in one direction, it's always easier to put something on the other side pushing back then it is to get people to stop pushing on the pendulum.
Walk backwards with me for a minute.
Let's assume that the next global circulation model to be published -- GCM-2007 -- is fundamentally correct, in that it can "predict the past" reasonably well. Say, its calculations over 1000 years (1000-2000) match data for overall trends in mid-continent temperatures and rainfall, and in mean sea temperatures.
OK, that's a heck of an accomplishment!
So GCM-2007 takes the following into account:
Let's work with GCM-2007 and figure out which of these three dozen factors/data compilations are most important to the model. We'll rank the top ten; "A" is most important of them and "J", the least.
"As you know" -- the last major iteration prior to GCM-2007 was GCM-2003. It wasn't quite as good as CGM-2007 because, while A through I were fully accounted for, those modelers didn't know about J. Thus it was absent from the model.
GCM-1999 was missing both I and J.
GCM-1995 was missing H, I, and J.
GCM-1991 was missing G through J.
Since GCM-1991 lacked so many of the factors that we now know are key to successful modeling, we can understand the frustration of the modelers of that long-ago time. They were constantly saying, "Darn it! I can't get this program to even approximately model the historical record, and I don't know why!
Except: Is that what the publications of circa 1991 actually stated? I haven't checked--but I strongly doubt it. IIRC, what they were claiming at the time was, "we have devised a progrem that successfuly models the historical record and offers insights into future climate changes."
But with benefit of hindsight, we now know that GCM-1991 couldn't have derived the historical record except by chance or artifice--it was missing equations to simulate factors G, H, I, and J!
I suspect two possible explanations (but entirely lack first-hand knowledge).
This, unfortunately, is how my long-forgotten DYNAMO model of the North Atlantic Cod Fishery was developed (see comment # 25). Have similar dynamics contributed to the GCMs of the past?
#87 AMac,
Bing o. Plus an excellent explanation. An excellent line of reasoning!
Now how many epsilons are in the model?
Imagined conversation:
CM= Climate modeler
Me: "Why do you have this factor epsilon in the model?"
CM: "It makes the numbers come out right."
Me: "What does it mean?"
CM: "I don't know."
BTW AMac the climate modelers were claiming that the models were good enough back in the 90s that for sure something needed to be done. Thus the birth of Kyoto.
Thanks to the rise of blogs this stuff is getting much more scrutiny.
Also note that the modelers do not release their code for indepenent review. We have no idea how many epsilons or coupled epsilons or iteration variable epsilons or variable dependent epsilons or nonlinear coupled epsilons are in the model.
Also we are trying to get a good picture with too few pixels. The chunks are too big in the models. We are trying to look at a high definition movie on a 64 by 64 pixel screen. Even if we have the color definition perfect it will be an ugly thing to watch. Add in that the sound while recorded at 16 bits is played back at two bits resolution and the experience is less than satisfying. Only geeks would pay for such a turkey (I once did a 1 bit DAC for voice - you could understand it - but no way you could tell who was speaking).
> Here's what you conveniently removed.
Let's see if it supports Mark's complaint about my criticism that his summary "is missing so many facts that it's useless."
>>>"Predictions about the future are murkier and there is less agreement among scientists about what might or might not happen, the range of possibilities and the liklihood of occurence."
While we're at it, let's see how Mark started
>>>There is a mountain of good science that says 3 things:
Mark says that there are three facts, predictions, and beyond that advocacy and politics.
He's wrong. That mountain of "good science" says more than three relevant things. There are, as I demonstrated, more facts (note that I pointed out that my list wasn't complete), and they're quite important. They're not predictions, they're not advocacy and politics. They're facts and they're relevant.
And then, there's the facts not yet found in that mountain. They're not predictions and they're not advocacy or politics.
>Wouldn't it have been easier to just have said, "I agree with mark?"
Why would I agree with someone makes the mistake of writing that there are only three relevant facts?
> One other question: do you sleep well?
Why would I lose sleep over Mark's error?
There is a mountain of good science that says 3 things:
1. the earth has warmed over the last 100 years.
2. the warming has accelerated over the last 13 years.
3. burning of fossil fuel contributes to both 1 & 2.
There's nothing murky about that.
Predictions about the future are murkier and there is less agreement among scientists about what might or might not happen, the range of possibilities and the liklihood of occurence.
After that comes all the advocates and politics.
The warmest year was 1998. The hurricanes are dropping off. Ocean heat is diminishing. It's cooling time again.
This question was asked in the original post: "Will the natural cycles which would otherwise plunge the Earth into a period of glaciation, a new ice age, overwhelm that warming contribution?" The answer to that is clearly no. The various participants in the debate over the Ruddiman hypothesis (including Ruddiman, Broecker and Berger) agree that the current anthropogenic CO2 contribution will hold off the next ice age for at least 40,000 years. (Note that this is much longer than any of the prior Pleistocene interglacials.)
More broadly, I want to emphasize that the Ruddiman hypothesis does not constitute any sort of challenge to AGW theory, but is simply one of a number of areas of active research about paleoclimate. (See here for an example of another.) This is not to say that there would not be critical implications of Ruddiman being proved correct:
The latest published version of the Ruddiman hypothesis (expressed last year in an exchange of three papers in Eos) is that the Holocene anthropogenic CO2 contribution was only about 10 ppm, but that an oceanic feedback process kicked it up to about 40 ppm (i.e., roughly from 240 to 280). Recalling that the competing idea is that this increase was a feedback of orbital forcing, the question is whether 1) the CO2 increase drove the .8C temperature increase or 2) orbital forcing drove the temperature increase that in turn warmed the oceans enough to make the CO2 outgas. (I'm ignoring a lot of details here.)
Far and away the biggest question in climate science is the size of climate sensitivity to CO2; to keep comparisons consistent, this is expressed as the amount of warming that can be expected if CO2 is doubled from pre-industrial levels (i.e. to about 560 ppm). The generally accepted range (per the IPCC) of the calculation is about 1.5C to 4.5C. So, if Ruddiman is correct and a mere 40 ppm was able to drive a .8C increase (or anything close to it), it is difficult to escape concluding that sensitivity must be in the high end of the range. If so, we are in for a potentially very rough ride out of the Pleistocene glacial period, an outcome that we are very probably already committed to since it is likely already too late to avoid doubling CO2 by mid-century.
Thanks, Steve--very useful synopsis. Come back often!
A rebuttal to Ruddiman's hypothesis.
(PDF file)
If AGW is truly such a global cataclysm in the making, why arent we running fore bore towards nuclear power (considering petroleum based power plants produce 1/3rd of US CO2 emmissions)? Even if nukes are as dangerous as the activists think, they are talking about at worst a regional disaster, paling in comparison to the supposed global apocalypse global warming has in store for us.
So why dont we hear about how we should be building nuclear plants as fast as possible from Gore and his ilk?
We all know the answer- they dont really believe their own BS and nuke plants arent in their luddite agenda either. This is about reforming society, not saving the earth.
Consider this:
Are there many motivations is more powerful than the quest for the accumulation of wealth?
Where the people who are correctly using computer modeling to predict stock performance for personal gain?
Unlike the climate record where we are requred to perform extensive archeology to extract parts of the data record, in stocks there are exact performance histories, trading records, and documentation of the factors driving those histories. Very smart people should then be able to produce models that predict future performance.
But they don't/haven't.
You may argue the complexity of human behavior, etc, and I would counter that there are at least similar complexities in the solar/planetary system.
So what makes us so smart that we can "model" climate change?
As an engineer I use models every day, recognizing that there is a significant "crap" factor in all of them. Only through extensive experience with my tools and examination of the failed predictions in the lab, have I learned to add "windage" that makes these tools useful.
I remain skeptical of "scientific results" driven by bought science, politically motivated, in a "climate" where dissent is not funded, discussed or tolerated. How can I believe what is published when you start with the conclusion?
Gerry
#91 Steve,
It could also be that we are below the low end of the range.
You know. Because the models are so bad.
There was over a 40 ppm rise before 1950. Did temperatures rise .8C?
Also note that because absorbtion is logrithmic rather than linear, the next 40 ppm will not absorb as much energy as the previous 40 ppm.
Suppose the feedback from water vapor is negative instead of the assumed positive? Then all the computer predictions are worthless.
So yeah if you posit the sky is made of ice sheets held up by long bamboo poles and you start cutting those poles the sky will eventually fall. Other wise if all that is not true you may be scaring yourself unneccesarily.
Which is fine. Some folks love living in fear. It makes them happy. And who am I to deny a man his happiness? As long as he doesn't expect me to pay for it.
BTW none of these "solar forcings" include our sun as a variable star. With fluctuations of unknown magnitudes and unknown frequencies.
AMac 87 - or anybody! - I have a dreadfully simpleminded question. If my aging brain doesn't deceive me, we were indeed getting a lot of warnings about the need for "action now" based on the predictions of what you're calling GCM 1991, GCM 1995, and so forth...based on predictions on the scale of decades.
So, my question is, has anybody taken unmodified versions of GCM 1991 and 1995, plugged in actual CO2 data from the decade since, and looked to see how well they "predict" what actually happened in the subsequent 10-15 years?
If it hasn't happened, is there any project out there - is it even practicable - to do this? And do you think it would be worthwhile? (It seems to me that such a method would provide a clue as to whether there's a systematic problem with the GCM methodology as a policy guide.)
Gerry (#95)
I'd sign your comment. Your comparison with the stock market is right. There are still a lot of things too complex to be modelled.
I've seen many failures on weather forecasting in the Mediterranean Western Basin, surrounded by mountains, along a warm sea and with far colder Atlantic fronts striking suddenly. It is true that in recent years it has improved, though it was necessary to set up a new local research center, to intensively use of a huge amount of satellite data... only to make predictions not beyond a week.
I think it is a very complex matter, and that ultimatelly it is being applied the same concept as Socialism towards the economy, that is, that the State knew better how to manage the economy than individuals, whilst the truth is the contrary. The economy of a modern nation is so complex that no state can direct it efficiently.
These arguments about climatic change are something similar. They are telling us that they can predict the evolution of such complex system as the world weather, with only 100 years accurate data. I don't think it is so easy.
Alberich #97 --
Short answer: I don't know, not my field. Anyone?
Longer answer, I think the 15 yrs that have passed since t the 1991 vintage models is too short a time frame to address the issue. After all, I can predict the climate of the next 15 years fairly accurately (It'll be pretty much along the lines of the average of the past 15 years.)
Though you pose a really good general question--I'd expand it in the other direction. In what ways are the 2007 state-of-the-art extrapolations of paleoclimate different from the estimates of 1991? How would GCM-1991 look in terms of how it predicts (retro-predicts?) those corrected data?
More generally still, are the computer programs that comprise GCM-1991 (etc.) usefully archived? As a History of Science exercise, could the complete files be located, downloaded, re-compliled on a 'modern' computer, and re-run?
J the concepts of socialism and climate change are bound together even more tightly than that. Like I said before, climate change is being used as the excuse to usher in a global command economy, step by step. If its proponents were actually as terrified of AGW as they claim we should be, their actions would be far different. The nuclear power question is the gold standard for seriousness on climate change.
Thanks! When time permits I will ask elsewhere.
It's interesting to me because it could mean the difference between, "we had some good models in the early 90's and now we have refined them" versus "we had some primitive models in the early 90's but now we have improved them." The former situation would make a stronger case for acting right now.
One thing that should be noted about the models, there are never any error bars. If you know anything about science or engineering this should strike you as a bit odd.
Alberich #101 --
Googling during some down time brought me to Roger Pielke's Climate Science blog. I don't know how mainstream the contributing academics are in the GCM community, but parts of the discussion in this WoC thread touches on issues that they bat about.
For instance, In this Climate Science thread, commenter Willis Eschenbach wrote,
There is also some interesting discussions of models at ClimateAudit
I've added a new post with initial comments on Ruddiman's book -- he does critique the previous models in at least some detail, based on an initial page-through.
#89 Andy,
We have just gone through an extraordinarily high count sunspot cycle. Which means high solar output. Has the temperature rise been adjusted for that?
Look, I cannot but to recall this summer stance of oil speculators, they were betting for a bad hurricane sesion, and a disruption of the Gulf production. Result: the oil plummeting. Again this fall, waiting for winter, what happened? Mild weather in great parts of American and Europe: second dive of oil prices.
Haven't they got any consultant services to predict such things? Of course they have. What happened then?
Weather forecasting is not an exact science. Clima forecasting is, in my opinion, something between science, futurology from one side, and politics, from the other.
I know that and increase in carbon dioxide yields higher temperatures in a laboratory. Will that happen in the Earth atmosphere? Who knows. Higher carbon dioxide levels might encourage plant growth, which in turn might stabilize that increase. The temperature might go up in some countries that feel comfortable with that change, such as Canada or Russia, which, in turn could ironically someday argue against the substitution of fossil fuels. Technological developments in nuclear fussion may reduce someday or dependence on such fuels.
Who knows?
There's a significant difference between short- and near-term WEATHER forecasting and long-term CLIMATE modeling.
Weather forecasting is much harder because there you are trying to nail down detailed behavior of a complex system in a limited area which is, nonetheless, influenced by the larger system.
Climate modeling deals with the macro level. It can reasonably achieve order-of-magnitude accuracy on many behaviors.
M. Simon, as I understand it the potential impact of the sunspots is small -- not nothing, but small as a percentage of solar radiation reaching the earth's surface.
As I mentioned in my second post, Ruddiman DOES address sunspots / variability in solar radiation in his book. He notes it, but regards its impact as peripheral to longterm trends.
#109,
Latest estimates are a .5% increase in solar output over the last 100 years. That is not small in terms of equilibrium temperature. In fact it is forcing. About .3 to .4 deg C from a strictly radiative stand point. Which is about what we have seen within the MOE.
Cosmic rays contribution to climate was mention in previous comments without much discussion. What is theorized in his book may be already outdated
An excellent primer on cosmic ray influence on cloud formation and experimental confirmation of the theory may be a major step in understanding climate. The 'Sky experiment' received little press in spite of its obvious implications.
Ruddiman DOES address sunspots / variability in solar radiation in his book. He notes it, but regards its impact as peripheral to longterm trends.
Since no one knows the cause of solar variability or its Fourier Transform for 10,000 or 100,000 years on what grounds does he regard its impact as peripheral to longterm trends? i.e. what reasons does he give for such a conclusion given his lack of data?
Stockmarket is not a good example because it has a feedbackloop with the program which is the reason why it wouldn't work if everybody uses it.
But you could look at oilfield or weather prediction programs. 50 years ago they didn't know/implemented a lot of the processes involved but their predictions were better than an educated guess
c.a. #113 --
The prior point holds. People are highly motivated to model the behavior of the stock market, because great success would lead to great wealth. Success in climate prediction is hard to evaluate and quantify; it's easy for the stock market -- $.
The modest performance of stock market prediction is not the consequence of feedback loops, it's a consequence of the difficulty of modeling complex, dynamic, nonlinear systems. If feedback was the culprit, the record of the past few decades would show a series of spectacular but short-lived successes by global modelers.
It does not.
That said, c.a. is right that if a progammer was successful in this quest, the fact of the accomplishment would itself alter market behavior in short order and invalidate the model (check Burton Malkiel's "A Random Walk Down Wall Street). Hurricanes and heat waves are unlikely to respond with comparable agency.
M. Simon, here's an idea:
Buy Ruddiman's book, read it and then report back a detailed critique based on what he wrote. It costs about $17 on Amazon plus S&H. I neither have time nor inclination to reproduce the book here, nor would a short summary do it justice for your purposes.
My post pointed Winds readers to a potentially valuable scientific hypothesis which refines the prevailing climate model, done by a highly qualified climatologist in what I believe is a scientifically sober and responsible way.
You believe that your expertise as a process engineer qualifies you to critique climate models. I won't argue the point with you, but neither will I stand in for Ruddiman himself. Go read the book and engage it directly if you want your critique to be seen as undercutting his model (rather than as a perfectly legitimate example of the questions we lay people might have upon reading about it).
Or better yet, buy his more expensive textbook Earth's Climate . The material in that textbook, along with journal papers you can find via Google Scholar, should provide more detail re: the techniques, assumptions and validation methods used for these models.
This suggestion is not intended to silence you, by the way. You clearly have a strong concern about climate modeling and you have some math skills and experience in a field that will make it easier for you than for many to learn more about how climate modeling is done. My suggestion is that you go do that and report back what you've found. If you're right, you can make a more persuasive case that way.
And yes, it's the scholar in me that makes these suggestions. Good science, and for that matter scholarship in the humanities, is done in the context of a long dialogue with the hypotheses and data that have come before.
Molon,
Great idea.
I'm living below tthe poverty line and having great trouble making ends meet. My one extravagance is a pack of Top roll your own tobacco every two weeks $1.50. I have a donation button at my site.
You make a donation I'll buy the book.
M. Simon, if you're able perhaps you would like to participate in this project for free. Another one of the many ways to learn more about the models that are being used and to apply your serious skills to this issue - we could all benefit from that.
M. Simon:
I'm no stranger to limited finances. I just Paypal'd you $20. I hope that covers the expense for the text in question. If not, I hope someone else will chip in (probably another $5 or so would do).
Best wishes,
Nort
I have just Paypal'd another $10.
I've added a post here with links to the actual source code and output data of one of the most influential climate change models, sponsored by the National Science Foundation and the Dept. of Energy.
I hope those interested in how these models work and what they do -- or don't -- take into account will avail themselves of the opportunity to go investigate those questions first hand.
Greg F., just a note to say I'm still exploring the links you've provided above and will try to find time to comment on them. Thanks for contributing them.
Also plenty of hedge funds do claim that they have computer programs that do make money. Another problem with stock programs is that they look only at the stock market data without looking at the real world data of the underling company. If you believe that the market is priced perfect than it isn't even theoretical possible to outrun the market
Molon Labe (#108)
There's a significant difference between short- and near-term WEATHER forecasting and long-term CLIMATE modeling.
That is right.
Weather forecasting is much harder because there you are trying to nail down detailed behavior of a complex system in a limited area which is, nonetheless, influenced by the larger system.
Well, in that case, why are they saying floods, hurricanes and other natural catastrophes would be more frequent? They are not nailing down the detailed behavior but they are saying it will be bad. Why?
Again this is like Socialism. Those scientist are telling us what is better, for whom? It is a sort of common good. Even if temperature raises, it would be good for some countries, or maybe for many.
Climate modeling deals with the macro level. It can reasonably achieve order-of-magnitude accuracy on many behaviors.
Is that really proved? How can you prove something whose experimental area is the entire World? How can you model a changing system that has run 3,500 million cycles but you only have some data of the last 100 and accurate data (satellite) of the last 35? I'd get a lot of laughs and an F for such a thing.
AMac (#114)
That said, c.a. is right that if a progammer was successful in this quest, the fact of the accomplishment would itself alter market behavior in short order and invalidate the model (check Burton Malkiel's "A Random Walk Down Wall Street). Hurricanes and heat waves are unlikely to respond with comparable agency.
AMac, check please that the entire climate change issue is based in the presumption that we can do something to stop it. We've got another human feedback loop to the system, with a much slower response, if you wish, but you got it as you got it in the stock market.
Thus before going into modelling, I think there are a lot of things to be discussed. Is climate influenced by human beings? How? Can we do anything to avoid this? Would changes in climate be dangerous? How? Where?
I think such discussions have happened before
The central theme of Malthus' work was that population growth would always overpower food supply growth, creating perpetual states of hunger, disease, and struggle.
Malthus modelling did not take into account that technological developments would increase the productivity of agriculture. However, we've got an advantage over him, we can see how climate modelling does not work in medium term predictions, at least at the level it is interesting for us (2006 Hurricane season and oil speculators), and we can also see new zero-emission production technologies, in spite of that, the climate change is a central issue, why? Politics.
I really hate the way politicians are trying to spread fear on climate change.
Well, in that case, why are they saying floods, hurricanes and other natural catastrophes would be more frequent?
Think of it this way. If you put a pot of cold water on the stove and turn the heat way up, two things happen. First, the water closest to the heat source gets hot. And then the water starts to move as the hot water rises and mixes with the cold.
What was a stable system grows less stable. Areas that were cold have hot water moving in. Areas that were warm have an influx of cold move in.
If I understand correctly, this is the basis for the prediction that global warming would produce more frequent storms, weather extremes in both directions (hot, cold, wet dry). That's why it has always bothered me to read people dismiss the possibility of global warming by pointing to some snow storm or cold snap somewhere. Such extremes are what you would expect if rapid warming were happening.
Over time, of course, the temperature of the atmosphere in various places would even out as the global climate as a whole stabilizes at a new and higher temperature. But during the transition, things would be unstable.
Thus before going into modelling, I think there are a lot of things to be discussed. Is climate influenced by human beings? How? Can we do anything to avoid this? Would changes in climate be dangerous? How? Where?
Most of those questions are precisely what scientists are trying to determine through data gathering, analysis and modeling. ;-)
I too hate the politicization of this issue. What we need is sober attention to the data we know, clear discussion of the strengths and uncertainties of our existing models, and a deep discussion about the tradeoffs and risks we face.
Cox & Forkum on Global Warming
So "skepticism done right" is to swallow whole the propaganda out of RealClimate? You should look at some of Hansen's speeches before you pronounce him some kind of objective source of scientific truth.
Look up comparisons of building a coal powered plant to the murder of scores of millions in the second world war and ask yourself if somebody capable of such over the top rhetoric can keep his biases in check in the production of data that supports or undermines his beliefs.
After completing that excercise, I suggest you ask yourself why his data is an outlier, showing more warming than satellite data.
Also, you might ask yourslelf why, when looking at a map of climate heat anomolies for the United States, you can clearly identify high growth cities in the Northeast, look for the NorthEast Megopolis, then notice cities like Buffalo and Detroit, that have shrunk, do not seem to have experienced the same "global warming"
Finally, as a skeptical inquiry, ask yourself why should a "global" phenomenon be localized to high growth urban centers? Or don't, since obviously, your aim is to feel smart by agreeing with those you percieve as smart, rather than actual skeptical examination of the evidence.
You could also read a paper puplished in the Journal of Geophysical Research - Atmospheres, late last year, by Michael's and McKitrick, shows that these traces of urban heat island effect contaminate the world wide data, and that the US data, as contaminated as it is, is actually the best of the lot.
But that would be the move of an actual skeptic, out to convince himself of the rightness or wrongness of a particular theory. I am not expecting such from you, trust me.
As for Ruddiman, I think he probably has something of a case, I think a new ice age would have been far more catastrophic than the warming we are experiencing and likely have in store.