So the thread mysteriously has disappeared … apparently a sock was involved.
As we left off I had made the point that it matters not if we know for certain exactly how much of current global warming is anthropogenic, it matters that we can model how much of an effect continued greenhouse emissions at current rates will have. Those predictions have been made and show a very low likelihood of keeping the increase below 2ºC, a reasonable likelihood of 3 to 4ºC, and some possibility of over 10ºC. Anything over 2ºC is likely to get really dicey really fast.
Unanimity on the exact magnitude of anthropogenicity of extant warming is inconsequential to the decision of action. If someone is asking me if they should throw some gas onto a fire in my house, I do not need to have proof that the fire was caused by arson in order to know that water would be a better idea.
BTW, mods, I really don’t want to recreate my cites, quotes and links. And there had been others who posted good intelligent comments who were not likely the alleged sock. Can nonsock posts be left intact when you do this? Or lock it instead. It seems that us law abiders are inconvienenced unfairly. My apologies for posting this here, but I do not want to have to go to the Pit with this annoyance either. No time.
Add me to those who would like the thread to be re-instated. It sort of lessens the incentive to “fight ignorance” if one finds out that one’s hard work in doing so might be wiped out just because one poster in the thread (maybe the OP?) was in violation of the rules.
The reason it’s important to determine the degree to which human activity exacerbates climate change is that it will help determine what is the most appropriate solution. For example, if scientists determine that human CO2 production is only a minor factor in global warming and that the primary driver is solar activity, reducing human CO2 production by 10%, 20%, or any other percentage you wish to choose will have minimal impact. If, on the other hand, human CO2 production is the primary driver, emission reductions and/or new sequestration technologies are the way to go. If you don’t know the root cause of a problem, solutions are very likely to fail.
Mind you, I’m not arguing that we should do nothing. More research needs to be done – and quickly – in order to better understand the mechanisms involved, especially in regards to the hypotheses put forward by the dissenters. The more quickly those ideas can be tested, the more quickly we can arrive at a course of action that we can be assured will have the desired result. But to go charging down the path of emissions reduction without first addressing the possible alternative causes is like distributing pricey antibiotics to everyone in the country in response to an epidemic – without first verifying that the disease is bacterial in nature.
Furthermore, additional studies of past climate change could help to gain a better understanding of the impact of the current extent of change. That, too, can help determine what is the most appropriate response. If, for example, Africa becomes wetter, how would we best balance the loss of species adapted to a savannah environment vs. the potential reversal of a long-term trend in the desertification of Africa? Are there potential benefits, or are the only impacts detrimental?
A global warming debate brew-haha and I wasn’t involved?!? probably, a good thing for my SDMB posting status. Anyway…long live the fight against ignorance, even mine. that is all.
Implicit in your discussion is some idea like “We know that global warming is occurring but we don’t know why (and, specifically, how much we are contributing to it).” This is in fact not really a correct view of the field. We know quite well from basic physical principles that the increase in CO2 (and other greenhouse gas) concentrations in the atmosphere we are producing will produce warming. We also have some pretty good idea of how much warming it will produce, although there is some uncertainties for various reasons:
(1) We don’t know quite how sensitive the climate system is to CO2 since there are complicated feedbacks in the system. However, a variety of different estimates seem to be converging in the neighborhood of 2-4 deg C warming for a doubling of CO2 concentration.
(2) We don’t know the answer to the sociological question of how much human emissions will increase in the future.
(3) There are some uncertainties (although I don’t think they are that large) in the carbon cycle itself which means that we don’t know exactly what proportion of the CO2 emissions that we produce will remain in the atmosphere and what proportion will be absorbed by the oceans, land, biosphere, … (At the moment, they are absorbing roughly half of the emissions although it is generally expected that this will decrease over time as some of the sinks saturate and, possibly, CO2 and CH4 are released from effects such as warming of permafrost areas in the arctic.)
The study of the warming that has already occurred, both detecting it and attributing it to a cause, is then a separate issue. And, here we now have strong evidence that most of the warming of the last 50 years is likely due to the increase in greenhouse gases. In fact, noone has been able to show how the warming seen since ~the 1970s can be explained without including the effects of greenhouse gases. And, we know with even greater confidence that greenhouse gas emissions will become the dominant cause of global climate change in the current (21st) century.
That is exactly what has been done for the last ~20 years. The question is when exactly one decides one has enough information to take action. A better analogy along the lines of the one that you make is that the epidemic is rapidly spreading with epidemologists estimating that there is very little time before it gets completely out of control and almost all of the scientists in the field agree that it is bacterial. However, there are a few scientists, many who seem to have associations with industries who have a lot to lose from the distribution of the antibiotics (I couldn’t think of a good specific analogy here), who run around spreading blatant misinformation or, occasionally, coming up with alternate possible hypotheses (sometimes plausible, although only rather infrequently spelled out to the point of being testable) for the epidemic. The question is at what point you decide to take action and distribute the antibiotics while continuing to do the research.
What you are trying to do is to demand certainty from science…which is incapable of ever giving us certainty on anything. (Science is inductive and all knowledge is technically provisional.)
By all means, further research will be useful and it will be useful to modify our approach as more knowledge becomes available. However, that is not an excuse for doing nothing.
To expand on this point of alternative hypotheses a bit more, it is insufficient, for example, just to propose that perhaps the sun is to blame. The body of work on anthropogenic climate change rests on several lines of independent evidence that all must be knocked down. For example, if you claim the sun is to blame, you have to come up with an explanation of how this happens since the known forcing due to changes in solar output is only very modest. You also have to explain how the warming has continued to occur over the last 20-30 years with essentially no change in solar output (I believe it might even be slightly negative)…i.e., even if you just arbitrarily scale up the known solar forcing due to change in output, you still can’t get good agreement with the observed temperature trends. Furthermore, you have to explain how the known forcing due to greenhouse gases gets decreased once feedbacks are included. And, you have to explain why the fingerprint from the warming looks like one expects from warming due to increased greenhouse gases in many ways such as in the structure of the warming within the oceans and estimates (based on this and perhaps other things) in regards to the earth currently being out of radiative balance (which would not likely be true if the warming were simply due to increased energy received from the sun).
No, I’m not demanding certainty from science. I realize that’s not possible. I am simply trying to make sense of the various conflicting sources that I have read. Most who favor immediate reductions in CO2 emissions speak as you do, that the phenomena involved have been thoroughly investigated and that there is consensus about causes and what should be done. I do see differing viewpoints, however. Are you suggesting that all of the dissenting scientists cited in this Wikipedia article , for instance, are spreading disinformation because of industry ties?
I mentioned solar effects as an example out of thin air, not because I have any specific reason to believe it is the cause. I was merely trying, as a non-expert, to create a plausible sounding “what-if”. The reason it sprang to mind is that something like solar activity would explain why Mars appears to be warming (one link ). If human-produced CO2 is the primary driver for climate change on earth, why would Mars be experiencing climate change at the same time? I think that’s a question that’s worth answering, and may have some bearing on the effectiveness of emission reductions that could cost trillions of dollars.
Yes, science works on what is the best explanation given the available data. But I do not believe that asking tough questions about a given set of explanations is a bad thing. Resources for solutions are finite, and I think we owe it to ourselves to be as sure of our answers as we can be.
There may be differing viewpoints in the popular press and on the web. However, in the peer-reviewed literature, much more is settled even while there are still very active areas of research and controversy. Look, you can find plenty of controversy in the popular press and on the web on evolution too but that doesn’t mean there is significant scientific uncertainty about the theory of evolution in explaining human origins and the current diversity of flora and fauna. We now have a joint statement from 11 National Academies of Sciences including that of the United States saying clearly that the science is strong enough that action should be taken.
As for your specific question, yes, most of those listed on that website as dissenting do have either industry ties, strong ties to right-wing organizations, or both. For example, Patrick Michaels has had support from Western Fuels Association, a coal conglomerate that is probably the single most vociferous industry opponent of the science of anthropogenic climate change. He is also a fellow at the conservative/libertarian Cato Institute. Fred Singer runs his own wacko anti-environmental organization called SEPP [Science and Environment Policy Project] and doesn’t even accept the science on ozone depletion that led to the Montreal Protocol and subsequent agreement that phased out CFCs and won the discoverers of the process by which these chemicals deplete the ozone layer a Nobel Prize in Chemistry.
Frederick Seitz is infamous for using his position as a past President (long ago) of the National Academy of Sciences to spread the Oregon Petition that included an article deceptively formatted to appear just like an article published in the Proceedings of NAS even though it never actually appeared there or any refereed journal and never would since it was riddled with errors and deception. The NAS found this so deceptive that they issued a press release explicitly noting that this paper had not appeared in any NAS journal and was in fact not in agreement with NAS reports.
Richard Lindzen is certainly the most respectable of the so-called “skeptics” and has contributed some real science and real testable hypotheses to the debate (although it is said that he too has taken money from Western Fuels) as he desperately tries to come up with proposed negative feedbacks to cancel out much of the warming due to greenhouse gas forcings. However, so far his hypotheses simply have not panned out…and some of them seem rather unlikely on the face since they would tend to imply a climate system that is much more stable than has been observed in the past.
On the other side of the coin, some corporations who have a self-interest in not believing in climate change (and were initially very skeptical) have now basically accepted the scientific consensus and, in some cases (like BP), are leading the way in emissions reductions. These companies include BP, Shell, and Ford. You can read their views on their websites.
As I discussed in the disappeared thread, Mars is very different with a very different atmosphere…so different that even if you showed that Mars was rapidly cooling, it would not convince many of those who are proposing solar hypotheses that this shows that the earth’s warming is not due to solar effects. A discussion of the warming seen on mars and why it is unrelated can be found here.
Asking tough questions is great and it is continuing to happen in the scientific literature. However, recycling arguments that have failed in the peer-reviewed scientific community (if they ever appeared there at all) is not great. And, continuing to demand ever higher amounts of certainty is not a realistic approach. You don’t wait until your house is definitely engulfed in flames before purchasing fire insurance.
A very good point. I am much more familiar with the scientific background of evolution because it was addressed in my schooling. Global warming, being more recently understood, was not covered back then. I admit I haven’t taken the time and effort to acquaint myself with the peer-reviewed literature. The info you’re providing is very helpful.
Also illuminating. While I don’t necessarily agree that right-wing=wrong, the energy industry ties are much more telling, as is the history of academic dishonesty of a couple of them.
Now that was a fascinating read. I’m surprised that the more responsible pop-science sites like space.com who make mention of warming on Mars don’t at least link to more complete information like this.
I think this is where spokesfolks for the scientific community need to do better PR work. Many statements that there is scientific consensus regarding the issue are simply shrill assertions that there is and how dare someone question it. It is far too rare for someone to take the time to point out (as you just have) places where a layman can read and understand more about the scientific consensus around the issue and the nature of the dissenters. Or, for that matter, places where information on a given question has already been addressed. Some of the dissenters, on the other hand, are very good at sounding reasonable if one isn’t familiar with the peer-reviewed literature.
A good start would be making sure that science-friendly media like space.com do a good job of making sure that they are not reporting information in such a way that it raises questions in the public eye that have already been answered by the scientific community. After all, if the science-friendly media outlets can’t get it right consistently, it would be a bit much to expect the general media to present things appropriately.
Oh, and while I have your attention, jshore, do you happen to have a handy source that gives a good layman’s synopsis of the impact of a 2ºC - 4ºC change?
I agree with you. Usually scientists are ill-prepared for dealing with this kind of thing, which is something that both dissenters on climate change and evolution have taken advantage of. Also, scientists tend to think that if they write volumous reports of good science (such as the IPCC reports or the NAS reports on climate change) this will somehow supplant the misconceptions that others have put out there. They fail to realize that unless the misconceptions are addressed head-on, this is very unlikely to happen. (This is sort of analogous to a finding in my field of physics that you can teach a whole course on Newtonian mechanics and such, even getting the students solving many numerical problems correctly. However, if you give these students a test with more qualitative thought questions, they tend to fall back to their incorrect “Aristotlean” preconceptions. In order to get them to change these preconceptions, you have to confront them directly and demonstrate to the students why they are false.
I think the closest thing to scientists in the field embarking on some PR work to directly address misconceptions and deceitful arguments are some of the articles at www.realclimate.org (the site that I linked to in regards to the Mars warming).
No problem. Glad that I could help and also that you seem to be open to changing your opinion with more information.
I have to admit that I am not very up on that end of things. Probably the best source of information would be the summary for policymakers (SPM) of “Climate Change 2001: Impacts, Adaptation and Vulnerability” of the IPCC report available at www.ipcc.ch. It is also worth noting that, while 2-4 C may sound fairly modest, I believe the global change in temperature between the coldest depths of the last Ice Age and now is only soemthing like 5-7 C. On the specific issue of ecological effects, there was also a paper in Nature last year which attempted to estimate what percentage of species would be “committed to extinction” by 2050 if the range of projected climate changes by the IPCC came to pass, obtaining estimates of 15-37%. (I believe this paper was the first of its kind to do this sort of estimate, so one would want to see other scientists weigh in on it before having too much confidence in this prediction.)
I wouldn’t be surprised. That article is an ongoing source of real conflict and we have banned more than one editor as a result of it. Most of the editors working on it are pushing some point of view or another, and some of them are very dedicated in their efforts.