Arguments
Is there a scientific consensus on global warming?
The skeptic argument...
There is no consensus
The Petition Project features over 31,000 scientists signing the petition stating "There is no convincing scientific evidence that human release of carbon dioxide will, in the forseeable future, cause catastrophic heating of the Earth's atmosphere ...". (Petition Project)
What the science says...
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97% of climate experts agree humans are causing global warming. |
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Science achieves a consensus when scientists stop arguing. When a question is first asked – like ‘what would happen if we put a load more CO2 in the atmosphere?’ – there may be many hypotheses about cause and effect. Over a period of time, each idea is tested and retested – the processes of the scientific method – because all scientists know that reputation and kudos go to those who find the right answer (and everyone else becomes an irrelevant footnote in the history of science). Nearly all hypotheses will fall by the wayside during this testing period, because only one is going to answer the question properly, without leaving all kinds of odd dangling bits that don’t quite add up. Bad theories are usually rather untidy.
But the testing period must come to an end. Gradually, the focus of investigation narrows down to those avenues that continue to make sense, that still add up, and quite often a good theory will reveal additional answers, or make powerful predictions, that add substance to the theory.
So a consensus in science is different from a political one. There is no vote. Scientists just give up arguing because the sheer weight of consistent evidence is too compelling, the tide too strong to swim against any longer. Scientists change their minds on the basis of the evidence, and a consensus emerges over time. Not only do scientists stop arguing, they also start relying on each other's work. All science depends on that which precedes it, and when one scientist builds on the work of another, he acknowledges the work of others through citations. The work that forms the foundation of climate change science is cited with great frequency by many other scientists, demonstrating that the theory is widely accepted - and relied upon.
In the scientific field of climate studies – which is informed by many different disciplines – the consensus is demonstrated by the number of scientists who have stopped arguing about what is causing climate change – and that’s nearly all of them. A survey of 928 peer-reviewed abstracts on the subject 'global climate change' published between 1993 and 2003 shows that not a single paper rejected the consensus position that global warming is man caused (Oreskes 2004).
A follow-up study by the Skeptical Science team of over 12,000 peer-reviewed abstracts on the subjects of 'global warming' and 'global climate change' published between 1991 and 2011 found that of the papers taking a position on the cause of global warming, over 97% agreed that humans are causing it (Cook 2013). The scientific authors of the papers were also contacted and asked to rate their own papers, and again over 97% whose papers took a position on the cause said humans are causing global warming.
Lead author John Cook created a short video abstract summarizing the study:
Several studies have confirmed that “...the debate on the authenticity of global warming and the role played by human activity is largely nonexistent among those who understand the nuances and scientific basis of long-term climate processes”. (Doran 2009). In other words, more than 97% of scientists working in the disciplines contributing to studies of our climate, accept that climate change is almost certainly being caused by human activities.
We should also consider official scientific bodies and what they think about climate change. There are no national or major scientific institutions anywhere in the world that dispute the theory of anthropogenic climate change. Not one.
In the field of climate science, the consensus is unequivocal: human activities are causing climate change.
Last updated on 16 May 2013 by dana1981. View Archives
What an irony that you are worried about people being sceptic but in the same time defend someone whose ideas neglect the validity of science in general.
I believe the link http://www.giss.nasa.gov/edu/gwdebate/ (NASA's Goddard Institute of Space Studies) should be http://www.giss.nasa.gov/staff/jhansen/gwdebate/
Prions were hotly disputed, and the idea of an infectious protein is about as jaw-dropping as it gets, but subsequently Stanley Prusiner won the Nobel prize for his research.
Science simply consists of explaining the most data with the least long-winded explanation (aka Occam's Razor). We use the model that the earth orbits the sun because the math becomes neat and tidy using this assumption. With the earth at the center, the math becomes intractable very quickly.
However, when discussing hurricanes and naval guns, folks like to assume the earth does NOT rotate, and a fictitious force called the Coriolis force must be introduced to correct.
We assume the earth is flat for laying out a garden, but need a spherical model to use for space travel. Physics uses the wave theory of light in optics, and organic chemists use stick and ball models, knowing they are incorrect, but convenient, models.
Everyone clear on what science is now?
The Asch conformity experiments in psychology show people will knowingly lie to conform when comparing lines on a piece of paper. No ambiguity. Other experiments show the less people know about a topic, the more they conform.
What happens when you have an enormously complex chaotic non-linear system (aka climate) whose inputs and outputs are not well understood, and conclusions are presented as unequivocable?
The bottom line is that climate science is a bit flakey from the get-go, the data have enormous variance, and the field is not helped by over the top WAG predictions a hundred years out.
The only reason it appears to have any traction, is because mankind can be blamed. There are far worse end-of-the-world-as-we-know-it scenarios with much better data, approaching almost certainty, that would merit more time and resources.
Any questions?
Nobel prizes are awarded only after a consensus is reached and Stanley Prusiner had to wait 15 years. Contrary to popular belief, this is how science works, a ground-breaking theory on something not yet explained emerges but it needs to convince the other scientists before it is accepted and form a new consensus. In real science there's no definitive proof but a (growing) amount of evidence.
climate change is a theory so how can there be skiptics
American Medical Association
In 2008, the American Medical Association issued a policy statement on global climate change declaring that they:
Support the findings of the latest Intergovernmental Panel on Climate Change report, which states that the Earth is undergoing adverse global climate change and that these changes will negatively affect public health.
--http://en.wikipedia.org/wiki/Scientific_opinion_on_climate_change
My point was that science is not "consensus". Science is Occam's Razor. The least long-winded explanation of a dataset is the current model.
Folks in the scientific world who are chicken to speak out, is not "consensus".
Stomach ulcers were thought to be caused by emotional distress, the consensus belief. Based on a plausible theory, with no one bothering to be skeptical about it. In 1982 a physician Barry Marshall proposed that a previously unidentified bacterium Helicobacter pylori was the cause. It fit the data better, which led to new treatment, that made some drug companies VERY unhappy. Folks back then thought Marshall was completely off his rocker to challenge "the consensus". Exactly like AGW skeptics today are thought to be unhinged.
Actually the only question in the whole of AGW, is whether anthropogenic CO2 emissions account for temperature data better than the random variances inherent in climate.
Right now, they don't.
Science is not Occam's Razor or parsimony or whatever you want to call it. People may use such approaches in the method of discovery but the model has to explain the evidence.
Watch this video, and see what consensus in science actually means.
Note to John: Perhaps you could link directly to Naomi Oreskes talk here or when talking about her survey here Of course I would obviously recommend you screen the talk and its suitability yourself first :P
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That link failed to address the key flaw in the Petition Project, so you could hardly call it a "complete" rebuttal. Namely, by the standards of the petition, 31000 represents about 0.3% of the targeted population, even with the most generous calculations.
Science is decided by evidence, not signers of petitions. The reason almost all major scientific institutions agree with the mainstream view of global warming is because the scientific evidence overwhelmingly supports it.
Notice the consistency on one side of the debate: CO2 is rising, leading to warmer temperatures and a potentially serious problem that should be mitigated.
Compare to the inconsistency on the skeptic side: it's not warming, it is warming but it's the sun, it's not warming, it is warming but it's el nino, CO2 is causing warming but climate sensitivity is low, it's cooling, it's warming but it's cosmic rays, it's warming and it's CO2 but cap and trade sucks, the hockey stick has been debunked, it's cooling, it's warming but it's water vapor, it's cooling because of the sun, it's a statistical mistake, it's warming, it's cooling.
Is that about it? Did I succinctly summarize the "skeptic" position correctly?
Yes and I pointed out that you were wrong, the link did not "completely" refute that video. The video points out that practically anyone with a B.S. degree is eligible to sign this petition. This is the key flaw in the Petition Project. The link you provided did not refute this claim.
U.S. National Academies today issues three reports from the National Research Council detailing climate change research results and remaining challenges, mitigation possibilities, adaptation requirements and hurdles.
This is where scientific consensus leads:
Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.
Summary, links to reports here:
Strong Evidence On Climate Change Underscores Need For Actions To Reduce Emissions And Begin Adapting To Impacts
The petition Poptech mentions is not very useful compared to what NAS has just published.
I think you mistake science for some kind of democratic process. Generally we weight the opinions of scientists on a topic as to whether they have a publication record in good quality peer reviewed journals related to the topic on which they have an opinion.
To illustrate why your democratic approach is faulty, consider biological sciences. Ecology and molecular biology are both important fields. Ecologists use a lot of molecular biology technologies, but are not domain experts in the subject - they follow procedures rather than have a deep understanding of the underlying science. Molecular biologists can create organisms that alter ecosystems, but with a small number of exceptions, their education in ecology is almost non-existant. As a result it would be very wrong to use the opinion of a molecular biologist on the topic of ecology because they don't know anything about it. I reckon the same is very likely for the people you describe as scientists who contribted to the petition. It has very little meaning as far as the science goes, it's a political action which is entirely unrelated.
Of the 80 speakers, I noticed that fully forty-five were qualified scientists from relevant disciplines, and from respected universities around the world -- from the USA, Canada, Mexico, Russia, Sweden, Norway, UK, Australia and New Zealand.
All of them have reservations about climate alarmism, ranging from concerns that we are making vastly expensive public policy decisions based on science that is, to say the least, open to question, through to outright rejection of the Anthropogenic Global Warming (AGW) model.
Several of these scientists are members or former members of the IPCC Intergovernmental Panel on Climate Change.
But how do 45 sceptical scientists stack up, you may well ask, against the 2500 on the official IPCC panels? But of course there aren't 2500 relevant scientists on the IPCC panel. Many of them are not strictly scientists at all. Some are merely civil servants or environmental zealots. Some are economists -- important to the debate but not experts on the science. Others are scientists in unrelated disciplines. The Chairman of the IPCC Dr. Ravendra Pachuari, is a Railway Engineer.
And of the remaining minority who are indeed scientists in relevant subjects, some (like my good friend Prof Fred Singer) have explicitly rejected the IPCC's AGW theory. Whittle it down, and you end up with fifty or so true believers, most of whom are part of the “Hockey Team” behind the infamous Hockey Stick graph, perhaps the most discredited artefact in the history of science. This is a small and incestuous group of scientists (including those at the CRU at the University of East Anglia). They work closely together, jealously protecting their source data, and they peer-review each other's work. This is the “consensus” on which climate hysteria is based.
And there are scarcely more of them than are sceptical scientists at this Heartland Conference in Chicago, where I am blogging today. Never mind the dozens of other scientists here in Chicago, or the thousands who have signed petitions and written to governments opposing climate hysteria. Science is not decided by numbers, but if it were, there is the case to be made that the consensus is now on the sceptical side.
"I’ve just returned from the Heartland Institute’s Fourth Annual Climate Conference, at the Marriott Hotel in Chicago, where something very interesting was emerging: a clear counter-consensus on climate change. Of 700+ delegates, 400 or so were scientists in relevant disciplines – arguably more than on the IPCC’s much vaunted panel (after you allow for non-scientists, scientists in irrelevant disciplines, and dissenting reviewers). These scientists came from around the world, and from highly respected academic institutions. They were by no means unanimous, but all (except for two token Warmists) agreed that the IPCC “consensus” is deeply flawed, and that the policy prescriptions based on the IPCC’s work are extremely unlikely to deliver significant results."
Looking forward to reading Robert Carters new book 'Climate -the Counter Consensus'
NAS has just released a rather stunning compendium of climate research findings, mitigation options and adaptation possibilities.
Here's the takeaway for us laypersons, from the climate research portion of the set:
Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.
You can find the press summary of the reports here.
A free-to-read version of the report is here
Now I'm sure that we'll hear squawks from people entirely clueless about what the National Academies represents to the effect that the NAS is simply ensuring that grant money continue flowing but consider, if their conclusion is that anthropogenic climate change is a settled fact beyond dispute, that hardly serves as an incentive to pouring more money into research, does it? In any case such an argument is worthless in terms of offering an alternative to accepted research findings.
"It calls for a new era of climate change science where an emphasis is placed on "fundamental, use-inspired" research,"
What is frustrating is that in the media the word "consensus" is used often with the catch phrase "a handful of dissenters" or "deniers" or "trouble makers" or something like that, but that is clearly not the case. ~20% is not an insignificant figure.
I also make the point that those of us in fields other than the earth sciences who criticise climate science for poorly collected and presented data coupled with poorly argued conclusions (in my/our opinion of course), specifically on AGW, would not have a high level of respect for the publications that come from climatology and to a lesser extent earth sciences on this issue. You are not providing much of an argument to us by quoting phrases like "peer-review" and "consensus" when refering to climate science. If wikipedia's explanation of the peer-review process is accurate then in light of the figures given in the article above, the "peer-review" process in the field of climatology (or more widely in earth sciences) may be a very biased excercise indeed.
Here is a link to the article:
The wikipedia article seems to imply that only a few reviewers are needed as a minimum and the editor of a journal does not need a consensus amongst them since their role is advisory only. The wikipedia article implies that only "experts in the field" would be invited to review and so the survey results provided in the article above reveals an obvious potential for group think during the peer-review process.
A survey of scientists outside of these disciplines would be much appreciated. How often is it said that climatology is a relatively new field? Well then... let some of the professors in the more distant fields of Physics, Chem, Mathematics and Statistics "Peer-review" these articles and we will see what kind of conlcusions are published then.
It is ultimately a discipline on trial and I would ask the question "Are experts from other disciplines even bothering to spend time critiquing publications on climate science or are the police left to police themselves?"
You may then say that the list of endorsing scientific organisations in the article above implies that the level of dissent in a broader scope of disciplines is roughly matched by the survey. Then please provide figures of % endorsed of worldwide scientific organisations etc. and I will be more willing to accept that. However, if the level of dissent within these sci. orgs is greater than that portrayed in the survey above then the picture of a "handful of dissenters" in my opinion may fall apart. Only the heads or a majority of the higher management of these organisations need to support the AGW view in order for the entire sci. org. to be listed.
Many dissenters within these organisations may not be speaking out about their position on AGW even in private to their colleagues due to the potential for work place friction on this highly emotive issue. They may also be fearing dis-favour with their own organisational heads/management, who have already made their position offically known. I'm not talking about a conspiracy just the complications of work place issues that arise when speaking out about this subject.
Sure majority rules and you may have it.. but don't tell me you have an overwhelming consensus until you can provide the overall numbers.
An opinion is not science.
Further to this I point out the potential for group think within the climate sciences as outlined above. Which in my own opinion (to which I am entitled and I utterly reject any idealised notion that science is devoid of opinion or opinions, look up the definition of consensus and you will find it is a pluralised synonym of the word opinion) highlights the fact that just because something is published that does not automatically guarantee a quality of work.
On top of that I would argue that many qualified professionals outside of the earth sciences may not even be engaging in a thorough critique of the data due to a lack of time or interest or perhaps an unjustified trust that work being done in fields distant to their own is of the same standard they would expect in thier own circles.
I'm 2 years late to the party, but for the record...
Nobody signed Inhofe's list. It was created by garnering selected quotes and adding the person saying/writing them. A good number of the people on it actually endorse the IPCC general conclusions, and some have even written to ask to be taken off.
Inhofe's 400+ is not a petition or a declaration, just a concoction of names and highly elided quotes.
Concensus only has meaning if there is no pressure to conform in either direction.
No pressure, indeed.
10:10 needs some grownup supervision.
No. They need withdrawal of corporate and government sponsorship.
Meanwhile, I'm wondering if 10:10 is hiding government sponsorship.
I'm wondering if 10:10 is hiding government sponsorship.
It does.
About 35,400 results (0.06 seconds)
And yes, I agree wholeheartedly, government sponsorship of all private enterprises has to be stopped, including fossil & biofuels, wind, solar, nuclear and oxen energy.
Obviously some taxpayer's money should go into basic research, but only if appropriate institutions are installed to make sure politicians don't have their say in how it is distributed. And no IPR tricks, papers written on research done using public money should go into the public domain.
Your search is misleading. That's local government agencies who have decided to participate in the campaign, not providers of sponsorship.
I hope your extreme libertarian statement is meant to be satirical by the way, as in any other context it makes no sense at all.
There's broad agreement on that, at least. I'm no expert (on anything) but it looks as though the emerging model going forward is for research budgets to include boosted publication fees, those fees to cover the costs of making publications permanently accessible on a freely available basis.
Trying to think of an analogy, the only one coming to mind is unfortunately that of purchasing a plot in a cemetery, where money for the plot pays for upkeep of the cemetery grounds, with no gate fee for those wishing to visit and pay their respects. Stretching the analogy past the snapping point, perhaps we may think of citations as being the equivalent of visitors leaving flowers...
Perhaps it's more like roads, tunnels and bridges. The authority or other developer's costs are met out of taxes paid by everyone, as are the maintenance costs. There is no restriction on how many kms are driven on those roads by any particular driver or vehicle, taxpayer or otherwise. The current system acts more like a toll road.
Not a very wonderful analogy, but you get the idea.
This is tending to be a requirement in NIH and EU funded research these days. I think we're a bit behind the times here in Australia, although I have an article going into a (free to publish in, and free to retrieve) open access journal sometime soon. But that's an industry-academic partnership body who are trying to raise their profile, so it's a bit different.
That's local government agencies who have decided to participate in the campaign, not providers of sponsorship.
You are kidding, are you?
David Cameron announces his ambition
spon·sor
The British government signs up to 10:10, assuming responsibility for the campaign and the group behind it, including a promo depicting reluctant kids to be blown up. A rather generous publicity boost for a private company while shooting themselves in the leg. Hilarious.
"Further, and crucially, the solution to carbon emissions will eventually be technological not ideological. Most personal efforts to show willing will in the long-run make no meaningful difference [...] their lobbying activities encourage empty promises rather than sustainable change"
My, what a political turn this thread has taken.
It's still about how to make consensus. The particular method promoted by the 10:10 team is proven to be effective in the short term multiple times throughout history, particularly here, in Central Europe. Should I say we are all too familiar with it?
Unfortunately however, it may not work so well in the long run, as sooner or later people are prone to come to their senses.
Perhaps you're unaware of the immediate retraction and apology concerning the video by the 10:10 group? Certainly puts your shrill hand wringing in perspective.
#236
Maybe - I'm still not convinced. But your google search was misleading as it showed participation in the campaign by a bunch of local government groups. Even adding the word "funding" or "financing" to your search doesn't clarify at all.
Now if 10:10 were to actually show up on people's doorsteps with the threat of physical violence, different story I'm sure. They didn't do that, they're instead using a crude cognitive bludgeon not properly crafted to achieve its intended effect, akin to putting on a blindfold and a boxing glove, then rummaging in a toolbox and expecting to find the proper wrench for the job at hand.
Likening 10:10 to the Ministerium für Staatssicherheit or the like is rather a ridiculous approach in itself. Again, if you're trying to inculcate fear in the audience here so as to engender an effect, you'll want to ground the risk you present in reality, not fantasy.
The topic of the thread is scientific consensus on the reality of climate change.
1: Even taking the high end estimates of future population and economic growth fossil fuels would not run out within 50-100 years. If we squeezed out every last bit we might get 200 years of continual expansion. Prices might rise (barring more cost efficient extraction technologies) to the point that these energy sources would be replaced by others, but they aren't going to run out any time soon.
2: Ditto nuclear power. We'd get less than a hundred years of power in 'once through' type reactors, but with more modern breeder reactors nuclear power could last for thousands of years.
3: Most projections DON'T have population and energy use growing continuously. Indeed, the mainstream view is that both will level off sometime during this century.
4: It is simply false that 'green technology' cannot match the power generated by fossil fuels and uranium. Indeed, potential wind power dwarfs all of those others combined and potential solar power makes wind power look minuscule.
Thus, once we have dispensed with the fictions we have considerably more options than 'die off' or 'institute population controls'... aka 'kill off'.
The point at which the CURRENT price of solar and wind is lower than the CURRENT price of coal for most of the world (it already is in some places, e.g. Hawaii) is still a decade or so off, but since we know the price of coal will rise (as you yourself argue) waiting until that point is short-sighted.
"CO2 is at 390 ppmv now and could easily be at 500 ppmv before coal even peaks. Experts say CO2 must be pushed back to 350 ppmv to be safe. Green thinking won't get us there; only downsizing will."
Another complete falsity. You could end all human industry and indeed kill off the entire human race and that wouldn't cause the atmospheric CO2 level to drop from the current 390 ppm down to 350 ppm any faster than switching over to 100% nuclear and renewable power.
As to BP's 'renewable uses up too much land' argument... in addition to already mentioned offshore wind and space based solar there are; high altitude wind, geothermal, hydropower, tidal, ocean heat flux, and simply citing wind and solar on 'dual use' land... e.g. wind in cornfields and solar over parking lots - more than enough available land.
A concensus IS a feedback loop. Especially if it exists in a scientific community.
How many new students in the climate science field come into the subject without an opinion on global warming? And what it the overwhelming opinion going to be? Pro, of course.
If you didn't believe in global warming, you would be crazy to choose climate science as a career.
So every new intake is already convinced of AGW, generally because of the concensus. There is your feedback loop, concensus naturally reinforces concensus and actually increases it.
In fact, in any field, most "experts" are understandaby apologists for the concensus.
There is an incredibly similar situation in the field of Bible study.
The huge majority of people entering the profession are already believers. What happens when they study in depth, and maybe experience some doubts?
Here's a good article
"Biblical Scholars
Here's another well written piece on why most "experts" are apologists for the concensus:
Most experts are apologists for the concensus
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The difference in religious studies and science is that science is self-correcting, using the most rigorous methodology of discovery humans have ever invented. Providing links to arguments about religious experts tells us absolutely nothing about science or the field of climatology.
Your statements regarding a "consensus" are yet another Argument by Assertion, a logical fallacy. I strongly suggest you spend some time at the Fallacy Files before posting here again. You'll be able to make a stronger case for your point of view.
And you don't attempt to refute my points, you are simply argueing by assertion yourself. I think you should reread your own link, and look up "irony".
A concensus IS a feedback loop. Especially if it exists in a scientific community.
There is scientific consensus on General Relativity and Quantum Mechanics and Darwinian Evolution ... Does that mean they're wrong ? Why should it for climate science ?
There is an incredibly similar situation in the field of Bible study.
I had a friend that lost her faith studying Theology. Her view was that the lecturers threw every argument against religion at the students to ensure students could overcome any "doubts". For her the doubts got the better of her. She was quite bitter about it :-(
However, my real argument would be that most science can be verified by experiment, and maths by proof.
Climate science is brand new, with no track record, and has a record of NO correct predictions so far.
( I mean real predictions, not retro ).
This is irrelevant. Most people believe in AGW because the evidence is there, and the science is convincing. One has to be pretty arrogant to assume that the majority of people going into climate science are led by irrational belief rather than actual scientific knowledge.
"If you didn't believe in global warming, you would be crazy to choose climate science as a career."
It's not a matter of belief, but of logical reasoning. We accept AGW as very likely true because the evidence clearly suggests it is.
"So every new intake is already convinced of AGW, generally because of the concensus."
The consensus exists because the science is pretty compelling. The fact the science is so compelling is the reason many contrarians choose not to debate the science, but rather attack the integrity of those who understand it by claiming (without evidence) they are victim of groupthink. This is what you're trying to do now. It's insulting, not to mention factually wrong.
"In fact, in any field, most "experts" are understandaby apologists for the concensus."
And that means they are wrong? Is a doctor an apologist for treatment because he's an expert in it? Is a general an apologist for good military strategy because he's an expert?
Your position seems to be that the more someone knows about something, the less we should trust that person. That's nothing more than ole' fashioned anti-intellectualism. the bane of scientific thought.
You assume the experts are wrong simply because you don't agree with the conclusion...that's not a logical position.
"There is an incredibly similar situation in the field of Bible study. The huge majority of people entering the profession are already believers."
Actually, the situation is very different, because Bible study isn't empirical science. It's simply the study of Christian religious texts.
Again, you try to attack the reputation of those you disagree with, this time by likening them to religious people. The sad thing is that, by espousing false ideas not based on logic and trying to discredit honest scientists, *you* are the one acting like the anti-sciece fanatical religious fringe.
most science can be verified by experiment
No, science is verified by observation. Experimentation is, of course, just a "fast track" way of making observations. For some sciences, (Astronomy, Ethology, Geology) experimentation is difficult, if not impossible; for others (Economics, Human Development) experimentation can be considered immoral.
Climate science is actually largely, if not entirely, the application of physics and a little bit of chemistry to a specific system - the Earth and its atmosphere. Experiments pertaining to climate science, and indeed think about the effects of CO2 on the energy balance have been going on for about 150 years.
One can of course say, "oh, they were just lucky" but that's really not sufficient.
I think I am therefore well justified in my conclusion that most people are initially convinced by the "consensus" rather than evidence.
You mention doctors, but many doctors are also homeopaths, and many are "experts" in homeopathy. The concencus of experts in homeopathy would be overwhelmingly supporting the effectiveness of homeopathic remedies.
Same applies to Chirpractic.
I'm not saying that climate science is as silly as these, I'm just pointing out that a consensus is naturally self perpetuating, till it's disproved.
That's why the consensus on AGW is totally valueless, as evidence.
You can make predictions in physics and chemistry, and verify them.
In climate science, you can't even predict next year's trend. But you can grandly predict the trend for the next century. Without the slightest risk of being proved wrong.