The 97% consensus on global warming
What the science says...
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97% of climate experts agree humans are causing global warming. |
Climate Myth...
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)
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.
Authors of seven climate consensus studies — including Naomi Oreskes, Peter Doran, William Anderegg, Bart Verheggen, Ed Maibach, J. Stuart Carlton, and John Cook — co-authored a paper that should settle this question once and for all. The two key conclusions from the paper are:
1) Depending on exactly how you measure the expert consensus, it’s somewhere between 90% and 100% that agree humans are responsible for climate change, with most of our studies finding 97% consensus among publishing climate scientists.
2) The greater the climate expertise among those surveyed, the higher the consensus on human-caused global warming.
Expert consensus results on the question of human-caused global warming among the previous studies published by the co-authors of Cook et al. (2016). Illustration: John Cook. Available on the SkS Graphics page
Scientific consensus on human-caused global warming as compared to the expertise of the surveyed sample. There’s a strong correlation between consensus and climate science expertise. Illustration: John Cook. Available on the SkS Graphics page
Expert consensus is a powerful thing. People know we don’t have the time or capacity to learn about everything, and so we frequently defer to the conclusions of experts. It’s why we visit doctors when we’re ill. The same is true of climate change: most people defer to the expert consensus of climate scientists. Crucially, as we note in our paper:
Public perception of the scientific consensus has been found to be a gateway belief, affecting other climate beliefs and attitudes including policy support.
That’s why those who oppose taking action to curb climate change have engaged in a misinformation campaign to deny the existence of the expert consensus. They’ve been largely successful, as the public badly underestimate the expert consensus, in what we call the “consensus gap.” Only 16% of Americans realize that the consensus is above 90%.
Last updated on 8 May 2016 by BaerbelW. View Archives
[DB] "If you wish to add anything further, I suggest you tone down your attitude and try to become scientific in this discussion."
Good advice; please embody it yourself so others may emulate your positive example.
Note, too, that unsubstantiated claims such as yours carry little validity and make you seem as if you are not very well versed in this science. Use of terms such as 'warmist' doesn't help make your case either.
Perhaps you could start by reading the original post, which deals with the idea of 'consensus' among scientists, not 'convergence' of climate models. Follow that by a thorough reading of the Comments Policy; if you cannot abide by that policy, your comments should indeed be deleted.
The thread about modeling, if you care to have a look, is #6 on the 'Most Used Climate Myths.' Read and learn. Then start asking questions; you'll find most here are glad to engage in reasonable debate. However, if you are here to just throw around jargon, make unsupported claims and lecture about your views on 'uncovering the truth,' you're wasting everyone's time.
No serious scientist deletes posts that disagree with their viewpoint. This magazine labels these as political or even more ridiculously that they're off topic and removes them.We know how much greenhouse gas has been produced by mankind, so assuming that the growth rate continues on trend, then you should be able to predict with a good degree of confidence what the global mean temperature will be in a relatively short time period, 5 years say. If you can't do this, and say that there are too many factors - mankind and nature - that prevent any level of confidence being attributed to your predictions, then your predictions are practically useless. There is still no concensus amongst warmists as to which greenhouse gas is the main culprit. Is it CO2 or methane? Both of which, of course, have both manmade and natural sources.[DB] "If you can't do this"
Straw man argument. Even removing exogenous factors such as volcanic effects and oceanic cycles, a trend of much more than a decade is typically needed for the underlying warming signal inherent in multiple metrics used to monitor global warming due to the noisy nature of the data.
"There is still no concensus amongst warmists as to which greenhouse gas is the main culprit."
100% incorrect. You will need to actually educate yourself more on this topic to understand just how wrong this statement is. This is the equivalent of saying that 2+2=a porcupine.
Trolling comments struck out. Future comments of this nature will be simply deleted. FYI.
[not DB] Use the Search box to look for "methane" without the quote marks. Then search for "Scientists can't even predict weather."
[DB] "Science is about trying to establish truth by coming up with theories and then demonstrating that new data meets the prediction that the theory made."
Imprecise; science is about developing an explanation (a hypothesis) that best explains what we can see and measure. Tests are then devised to either support or disprove the hypothesis. Those hypothesis that withstand the test of time and much research are then called "theory". One such is the theory of gravity. Another is the theory anthropogenic global warming. This link may help.
"Creating a site where only warmists are allowed to attack arguments that critics of the science (labelled as denialists) have pointed out is not science."
Two misconceptions here. This site was created to debunk the logical fallacies of those who pretend to try to poke holes in the research by ignoring the evidence which contradicts their position. The second misconception is that the term denialist refers to those who ignore evidence contrary to their position, no matter how damning. If you prefer, substitute the term fake-skeptic on those occasions you encounter the term "denialist" on this website. They are interchangeable.
The remainder of your comment, unfortunately, devolves into ideology and misunderstandings of what science is, and isn't. Please read the Comments Policy.
[not DB] Use the Search box to search for "models are unreliable" without the quote marks.
[DB] "and there are lots of them."
Unsupported assertions. Be specific, put your objections on the appropriate threads (use the Search function; 4,700+ threads exist here).
Your use of the terms "warmists" betrays ideology. Please study the Comments Policy & constructe future comments for better adherence to it. Future ideological and/or inflammatory comments will simply be deleted and your posting privileges may be curtailed.
Your use of the term "concensus" shows a lack of understanding of the scientific use of the term.
Inflammatory snipped.
What exactly is my supposed political agenda here?[DB] Please refrain from introducing politics into the discussion. This is not a thread devoted to politics & climate science (others do exist that cover that).
Also, your discussion of models is off-topic on this thread. Please use the Models are unreliable thread for that. Thanks!
[DB] Moderation complaints snipped.
Please note that posting comments here at SkS is a privilege, not a right. This privilege can and will be rescinded if the posting individual continues to treat adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.
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