Yes, but I’d like a specific example of how that data might manifest itself. For example, it would be an unbelievable statistical fluke if certain model predictions and the observed data kept agreeing year on year: this is, after all, how science proceeds in all kinds of other fields such as evolutionary biology. What level of correlation between model and observation would satisfy you - would similar levels as that which justifies publication in a respected peer-reviewed scientific journal in other sciences suffice?
What we can do is look at the assumptions we have made concerning the magnitude of effects and then make predictions of what should occur if those assumptions are true that should not occur if they are untrue. We can then wait and see if the predictions come true.
Isn’t this begging the question? If we could model the human input relative to the overall factors, then we would know the answer already. In other words, how do we classify our errors into wrong assumptions or wrong modelling of the mechanism of those assumptions?
Did you misunderstand what the term “extreme events” means (which should be obvious from the link I gave you) or are you just playing semantic games here? [For those who don’t know, extreme events refers to floods, droughts, record high temperatures, and the like. It does not refer to “what might happen if things are extended to their extreme position.”]
Do you happen to know what number of scientists are funded by the IPCC? You seem to imply that you are but my impression is that if this is the case you are one of the lucky few. As this page explains, “the IPCC does not carry out research nor does it monitor climate related data or other relevant parameters. It bases its assessment mainly on peer reviewed and published scientific/technical literature.” And, in fact, I haven’t seen many scientific papers in which the acknowledgements section listed funding from the IPCC.
My guess is that many scientists would give the IPCC a “negative acknowledgement” as eating a lot of their time that they would otherwise spend on their research. In fact, the NAS report on climate change that the Bush Administration commissioned in 2001 worried that the large amount of time taken by participating in the IPCC process might create problems in the future saying “Alternative procedures are needed to ensure that participation in the work of the IPCC does not come at the expense of an individual’s scientific career.”
You seem instead to be implying that the IPCC is serving a major role in advancing scientific careers by providing funding. I’d like to see evidence of that.
The debate has moved far afield since you made your request, but I’ll help you out since you don’t understand what a strawman is.
First of all, I was clearly paraphrasing you in my quote, so of course I can’t find an exact quote that matches what I said. What I can do and will do is list some of the quotes that made me think that was a reasonable paraphrase of your position.
For example, in a previous quote you said this:
You also said:
See, this is the sort of loose language that will lead people to believe you think things like “we can’t exactly delineate the difference between global warming and climatic variation.” If you think there is some important distinction between this paraphrase and what you said above, please, enlighten me.
Now as for this part of my paraphrase:
You said this:
Which clearly leads a reasonable person that you think it quite reasonable that solar heating is a plausible alternative explanation to the Earth’s warming, one that far outstrips global warming due to human activity. Granted, you never said it in so many words, but in many of your posts you have made it quite clear that you think natural climactic cycles may be the real cuase of global warming, and it’s quite disingenuous of you to say otherwise. If you think global warming via human activity is a major cause of global warming, please say so. If you think it isn’t, say. But this business of piling up quotes about solar heating and natural climactic cycles and then denying that you have a point in doing so is … disingenuous in the extreme.
You also said this:
Which is directly relevant to my paraphrase:
It is true that there are other potential solutions to the issue of global warming than the Kyoto Accords. But in the course of many lengthy posts, you have not advocated one of them. So while it’s true you never said the best thing we can do about it is nothing, it’s reasonable to assume that if you thought there was anything we should do, you would have advocated it, for you have certainly had every opportunity to do so. So your default position is quite reasonably describable as “do nothing.” If you do have a solution or solutions you advocate, feel free to sing out, cupcake.
Thus I was completely reasonable in my paraphrasing of your position, and far from creating a stawman, was summarizing it accurately. Accurately summarizing a position is NOT creating a strawman. You said the words, now stand behind them. Accusing us of building strawmen for drawing the natural, logical inferences in your posts simply doesn’t impress.
By the way, I missed this link previously (perhaps partly because you messed up the link which I have fixed in the above quote). But, it is important to note that the graph shown has been extended (and problems near the endpoint of that one corrected) by one of the original authors (Lassen) and it now shows a significant deviation between the correlation starting around 1980:
By the way, just to clarify my personal view: I don’t believe that scientists directly lie about what they think in regards to the health effects of smoking because they receive direct funding from the tobacco industry, nor do I believe that scientists directly lie about what they think in regards to global warming because they receive direct funding from industry or right-wing think-tanks.
Rather, I think that there are always going to be a small minority of scientists whose own political views and such are so strong that they will be unable to look at the evidence objectively. These are the scientists who then are recruited by or gravitate to these organizations.
We have seen clear evidence in other fields (such as tobacco and evolution vs. creation or intelligent design) that one can manufacture controversy long after the general scientific consensus in a field has emerged through this sort of technique. And, one can then claim that this controversy shows that there is still legitimate scientific arguments on each side. Hell, perhaps the best description of this sort of strategy in regards to climate change was given in a memo by Republican pollster Frank Luntz:
Basically an admission that they are lying and know they are lying. This is what gets me. The climate is screwed, the disaster is ongoing, dreadful feedback loops like the tundra melting and releasing methane are kicking in and still people are playing politics like it’s just something that can be dismissed with sleight of hand like invading a country under false pretences.
And still there are lunatic apologists that see conspiracy behind the overwhelming global scientific consensus on man-made global warming while swallowing the self-interested obfuscations of a handful of industry shills.
Well, I think that people have just begun to address this question in a semi-rigorous way. Here is an article that I linked to above that attempts to address this question: “To Hedge or Not Against an Uncertain Climate Future?”.
[/QUOTE]
On the contrary, it’s not argumentum ad populum. Argumentum ad populum is the fallacy that states because it’s popular, it must be correct (in that direction of causality).
In this case, the argument is not that it is correct because it is popular, the argument is that it is popular because it is correct (in that direction). If climate scientists did not have access to the data, did not publish in peer-reviewed journals, then things would be different.
If it is impossible to conclude a scientific investigation without unanimity, then there would be very little scientific “truth” – after all, there are (respectable) scientists who disagree that HIV causes AIDS (because there are HIV+ patients without AIDS), or that general relativity is true (because there are problems with GR), or that species descended from common ancestry (because of whatever reason).
From a scientific level, it doesn’t matter whether you’re in the majority or the minority, and if you look at scholarly articles, you can see both sides of the debate represented. I agree with Blake in the sense that people in the scientific minority should fight for what they believe to be true – as long as they can back it up with science.
However, from a political/policy level, it certainly does matter that the vast majority of scientists agree on anthropogenic global warming. For example, the National Academy of Sciences, whose explicit purpose is to counsel the U.S. government on scientific matters, has put out a positive statement on anthropogenic global warming. That is, regardless of what debate goes on in the scientific field, every possible indication from a political viewpoint is that scientists have given their recommendation. Debate among non-scientists as to what science says is obstructionist - that is, non-scientists, particularly politicians, are playing up a debate which does not really exist.
Debating the virtues of Kyoto is completely irrelevant at this point, because people have not agreed on the problem.
- Is global warming real?
- If global warming is real, is it anthropogenic?
- If global warming is real (but not necessarily anthropogenic), what are the effects?
- If global warming is real (but not necessarily anthropogenic), what can we do to stop/slow/reverse the trend?
- If global warming is real, anthropogenic, and the consequences are significant, are the solutions proposed feasible in light of the costs?
The problem here is that people are jumping to the final question before settling the first. The first three questions rest entirely in the hands of scientists - that is, policymakers (should) have very little to say about whether global warming is real, or anthropogenic, or what the effects are. The NAS is specifically designed to answer such questions, and it has.
Data generated from climatology needs to be averaged, at the very least, over 11 years (sunspot cycle). In order to get two data points (a line), you’d have to wait about 22 years.
I think you put way too much emphasis on computerized climate models and far too little on the data that we already have. The Vostok ice core provides very strong evidence (Nature articles for 1987 are site-liscenced so I cannot provide a direct link) that CO[sub]2[/sub] and temperatures are very strongly linked.
Nobody seriously contests that anthropogenic CO[sub]2[/sub] sources swamp out natural CO[sub]2[/sub] sources, and nobody seriously questions that increasing CO[sub]2[/sub] will increase the greenhouse effect. So we know that humans --(definitely)–> CO[sub]2[/sub], CO[sub]2[/sub] --(most likely)–> increased temperatures, and historically CO[sub]2[/sub] <==> temperature. We have no reasonable mechanism by which temperature might cause an increase in CO[sub]2[/sub], and based on this evidence, the vast majority of scientists have concluded that humans ----> increased temperature.
It is only in the magnitude of the effect (and what it is relative to natural forcing conditions) that is being debated.
- That anthropogenic global warming is happening should not be in doubt.
- That other factors may play a minor role in non-anthropogenic global warming warrants investigation, but is agreed by scientists to be minor.
- The consequences (and magnitude!) of global warming are debatable, but most people agree the consequences are significant.
I agree that the domestic policy such conclusions warrant is hotly contested; I respect people who think that policy should lead based on the evidence, and I respect people who think that policy can wait based on the evidence.
However, I cannot respect non-scientists who seek to meddle with the evidence based on political opinions.
Welcome, to the SDMB, aamco. I really hope that you stay around. I thought your above post was awesome and stated very eloquently some points that I wish I had made.
Absolutely. I too am glad that people like Richard Lindzen is around proposing hypotheses in a desperate attempt to try to explain how increasing concentrations of CO2 could not lead to very much warming. I think that the scientific community is stronger because of it. (When he writes misleading op-ed pieces in the Wall Street Journal, on the other hand, I think he does science a disservice.)
But, as you note, at the end of the day, we still have to make policy decisions on the basis of the best understanding of the science at this time.
And, here (PDF file) also is a more recent joint statement by several of the National Academies of Sciences, including the U.S. one. It states in part:
I’m trying to summarize Jshore and Blakes positions. This is how I see it so far:
Question:
-
Is the globe warming?
Jshore – yes
Blake - -yes -
Is the warming due to climate changes?
Jshore – almost certainly yes
Blake – looks like it but other factors have not been ruled out. -
Is CO2 increasing?
Jshore – Yes.
Blake – Yes. -
Is the climate change due to increases in CO2?
Jshore – Yes, to a very large degree.
Blake – We can’t say. -
Is the climate change natural or manmade?
Jshore – there is significant evidence to indicate that a very large part is manmade.
Blake – there is no way science can presently determine if the climate change is natural or manmade. -
Can we do something now about global warming?
Jshore – Yes. We can reduce CO2 emission, search for alternate fuels, sucking up and storing excess CO2, signing the Kyoto accords.
Blake – Yes, we can do all that. -
Should we do something now about global warming?
Jshore – Yes, all of the above.
Blake – Give us 5 years or so to come up with and verify accurate predictions before doing stuff that will be expensive and possibly not help. -
Why should we / should we not do something now?
Jshore – we should because if we don’t we will suffer dire consequences in weather etc. caused by an increase in CO2 that is avoidable by doing something to reduce CO2 emission now. If we wait it will just get worse.
Blake – we should not do anything painful regarding reduction of CO2 right now because we don’t have enough data to tell us that reducing CO2 will reduce global warming let alone whether we are contributing to warming by manmade means. -
What do scientists in this field say?
Jshore – Most scientists agree that CO2 is significantly contributing to global warming and that a significant contribution is manmade.
Blake – There’s no consensus among scientists as to whether CO2 is a main contributor to global warming. There is no consensus as to whether CO2 generation by man is a main contributor to increased levels of CO2. -
Why do they say that?
Jshore – Though not conclusive, the evidence clearly suggests it.
Blake – Some accept that the data supports CO2 induced global warming enough to start doing something about it. Others believe that without stronger scientific evidence no conclusion can be made. -
Can we trust the scientists?
Jshore – Some have an axe to grind. Industry funded scientists are more likely to come to conclusions friendly to industry.
Blake – A lot of scientists are going to study/produce results they perceive their benefactors will like.
If this is accurate then the thing to debate would be: “We have enough scientific evidence to conclude that global warming is mostly due to manmade generation of CO2”.
Jshore would be pro and Blake con.
Anything else right now would seem to be a distraction.
Right?
Maybe I missed it, but I haven’t seen where Blake is saying that 5 years down the road we should start doing things (or at least it isn’t clear what evidence in those 5 years is needed to convince him)…and while perhaps our Blake is close to his tipping point, I see little evidence that many of those wedded to doing nothing will abandon that position in 5 years.
I doubt that Blake would defend the completely untenable position that there is no consensus as to whether man is the main contributor to increased levels of CO2! I think what he did try to say is that there is some uncertainty around what fraction of our CO2 emissions will be absorbed by the land and oceans and what fraction will remain in the atmosphere, which I don’t disagree with, although I believe most of the scientific understanding is on the side of the “sinks” beginning to saturate rather than starting to take up more and more of the emissions. (Currently, roughly half of our emissions remains in the atmosphere and half goes into the sinks.)
Well, I would not claim that it is only industry-funded scientists who have biases. What I would claim is the process of science makes it extremely difficult for a strong bias to pervade most of an active and closely-watched field to the extent of strongly influencing nearly all of the results obtained in the peer-reviewed literature. Thus, if it were just a few scientists funded by Greenpeace and NRDC who believed that anthropogenic global warming was a serious issue and the rest of the peer-reviewed scientific community didn’t, then we would want to accept the fact that those few scientists likely have biases and accept the consensus of the scientific community (with the understanding, as always, that all scientific knowledge is provisional and new facts down the road might change our view).
This is a nitpick, but yes we can.
Take a perfectly nice polynomial like y=x[sup]3[/sup]-x. Goes up, goes down, goes up again. Second derivative (acceleration)? y’’=6x. Positive for x>0, even though the curve is descending in between x=0 and x=1/sqrt(3).
It might interest you to know that the U.S. Census Bureau uses 90% likelihood as the line of demarcation between statistically significant and not.
Seriously, as jshore has already said, nothing’s magic about 90%, 95%, or 99%. Their importance is that in fields where statistical experiments are reasonably frequent, there has to be an agreed-upon level to distinguish significance from statistical insignificance, otherwise anyone can say any damned thing they want to. Different fields choose different confidence levels for different reasons.
But this is a bit different: we know the planet is getting warmer, but we can’t take a sample of 100 Earths and put them in a lab under a sunlamp to see what happens 95% of the time. We may have to make a decision with less than gold-standard certainty; this is where science interacts with social policy. The scientists can tell us what they know, and how certain they are - whether or not they’re 95% certain. Then we, the body politic, need to decide what to do with the information, whether it’s complete or not.
One thing BushCo was right about is that sometimes the downside of doing nothing is sufficiently consequential that you have to act before you have complete knowledge. They were talking about Iraq and WMDs, of course, and their fingers were on the scale - but that only makes them wrong about Iraq, and not about the general principle.
RealClimate just put up a discussion on the Mars South polar cap measurements. It turns out that climate on mars is a quite complicated phenomena (and quite different from that on earth due to the large differences between the planets) but in fact the global climate on mars has generally cooled since the 1970s while the earth’s had warmed (although this cooling is understood as being essentially due to the level of dust-storm activity rather than a cooling sun).
All in all, the use of this piece of scientific data on the Mars south polar cap by non-scientists to jump to conclusions that are completely unwarranted by the science itself is an example of the selective filtering by some; they are willing to ignore the mountains of evidence that scientists are assembling concerning the global warming on earth but are willing to jump on…and dramatically misinterpret…any piece of scientific evidence that seems by some vague train of logic to fit their own preconceived notions regarding climate change!