Arguments
New Video: John Cook and the 97 Percent
Posted on 20 June 2017 by greenman3610
This is a re-post from Climate Crocks
Scientific conclusions derive from an understanding of basic laws supported by laboratory experiments, observations of nature, and mathematical and computer modeling. Like all human beings, scientists make mistakes, but the scientific process is designed to find and correct them. This process is inherently adversarial””scientists build reputations and gain recognition not only for supporting conventional wisdom, but even more so for demonstrating that the scientific consensus is wrong and that there is a better explanation. That’s what Galileo, Pasteur, Darwin, and Einstein did. But when some conclusions have been thoroughly and deeply tested, questioned, and examined, they gain the status of “well-established theories” and are often spoken of as “facts.
“There’s no such thing as settled science” and “science does not work by consensus”, are things we commonly hear from people who really should know better.
The earth revolves around the sun. Apples fall down. Oceans expand when warmed.
These are in fact, examples of “settled science” – accepted by consensus. We don’t re-litigate them in every paper about gravity or astrophysics.
If you google “climate, 97 percent consensus” or some permutation thereof, you’ll be treated to page after page of climate denial nonsense, some elaborately produced, some not, seeking to knock down the idea, essentially, that scientists believe in science.
Climate deniers understand that the scientific consensus is a critical gateway belief, one that most Americans are still unaware of, that makes citizens much more likely to understand the gravity of climate change, and support efforts to curb it.
So a lot of effort goes into attacking this idea.
While the “97 percent of climate scientists agree planet is warming and humans are the cause” meme has gotten pretty good penetration in the main stream media – most talking heads are aware enough to include that in any discussion of climate – in the social media sphere, the National Academy of Science does not have as strong a presence as jackasswithablog dot com.
In spending a lot of time interviewing John Cook, the author of the study so hated by climate deniers, ( and now replicated by a number of teams) – I had a goal to create at least one halfway decent, credible, well produced video tool for science warriors in the unending Facebook, email, and discussion group wars that shape a good portion of our public dialogue.
So here it is – deploy, deploy, deploy.
Hearing Dr. Cook himself explain, briefly, how the figure was arrived at, is worthwhile, as is hearing from several other researchers who have come to similar to results.
Most telling in the stats, — the more expertise respondents had in areas relevant to climate – the more likely they were to strongly support the consensus.
"There’s no such thing as settled science” and “science does not work by consensus”, are things we commonly hear from people who really should know better. "
I agree for all practical purposes many science theories are settled, like the earth orbiting the sun, and basic equations of gravity and the greenhouse effect. The sceptics take uncertainty in some areas of science, and try to falsely claim this means everything is uncertain. There do remain mysteries at the deepest levels of particle physics, but this doesn't obviate basic theories and laws and evidence of physics and chemistry etc, because the laws work in the real world, and you have observable cause and effect.
The climate sceptics claim theres no consensus, when there plainly is, proven by at least 5 polls and studies now, including the important Cook study. We have to use the evidence we have, and we have several consensus studies all pointing in the same direction, and all using different methods. This is a strong confluence of evidence, and we have no study showing anything significantly different, despite the fact nothing is stopping anyone trying to find a different result for over 20 years now.
Science does work by consensus. You have the majority of scientists agreeing that a theory has been sufficiently debated, and things point strongly in one direction. This is the only way we the public can have faith in a theory.
Of course nobody seriously claims a consensus is proof, and proof belongs only in mathematics, and self evidently a consensus could be ultimately proven wrong, but a consensus is based on the views of trained people, so is very significant. The duty is on people to find compelling evidence it is wrong. The climate sceptics have failed to provide a compelling critique or alternative theory for over 20 years, so its just not going to happen.
Governments often have to make policy choices based on new science, and they obviously look at majority scientific opinion, ie the consensus. There is no other sensible alternative. If governments choose to believe some eccentric, this would be irresponsible, and they would certainly need some utterly compelling reason, and they have singularly failed to provide one over climate science. Trump is a good example of somebody who has not come up with a remotely sensible reason to ignore the consensus, simply because there isn't one.
I am not a climate change denier. I just want to understand why nobody seems to be talking about all the fresh water pouring into the current. Why is there no discussion about the possibility of an ice age? Do we know how much fresh water it would take to stop the current? Can we even have a conversation about the possibility without being dismissed as religious fanatics?
Curiousbev @2, scientists have had considerable discussion of the input of fresh water from the melting of the Greenland icesheet on the Atlantic Meridional Overturning Circulation (AMOC). This has been discussed in the IPCC AR (Chapter 10), which concluded that:
It was also discussed on the IPCC AR5 (Chapter 11), which was more cautious, concluding:
That low confidence, however, means the current influence of AGW on AMOC is weak, so that the possibility of an abrupt change in the 21st century is still low.
With regard to the possibility of a change in the AMOC initiating a new glaciation, Dana Royer has shown that such an event is unlikely with CO2 concentrations of 500 ppmv or above; and hence very unlikely given AGW
[PS] Another recent paper looking at this is here but not expecting anything dramatic this century.
What is actually meant by the term "abrupt change" ? And what is a possible scenario, even if it's unlikely to actually happen?
The IPCC report related to this overturing circulation is very long and technical to read right through.
We all know "The Day After Tomorrow" scenario can't happen that fast (rather good move though) but what is a more likely scenario and timing?
Or do I just have an unhealthy fascination with disasters and horror stories?
nigelj @4, from Alley et al (2003)
Reference 2, from which the first sentence appears to be quoted, is the NAS report on abrupt climate change.
The classic case of abrupt climate change is the Younger Dryas, which in Greenland saw a change in precipitation patterns over 3 years, and in temperature over 50 years, although the change was much slower in the tropics.
Based on that definition, the end of glacials, which takes thousands of years, counts as abrupt, whereas a similar warming from AGW over a century or two may not count as abrupt if it follows change of forcing smoothly. There is, of course, a considerable risk that it will not.
TC @5, that's interesting. There have certainly been some short and quite intense cooling and warming periods, so the day after tomorrow is not quite as out theres as it seems. The current rapid arctic warming seems to fit the definitions of abrupt regional climate change.
An analogy for abrupt climate change might be an earthquake.
nigelj @6, the day after tomorrow gets the science almost completely wrong in every way. You might get rapid cooling with an AMOC shutdown, but not a turn around in days. Nor would you get supercells so large and so intence that they are effective vacuums in the eye. Nor, with rapid cooling, would you get snowfall sufficient to bury multistory buildings within a matter of weeks (cold water equals low precipitation), nor a sudden seal level rise (in a matter of days) from current to sufficient to float a ship through NY streets.
And last, and worst of all, what happened to that wall between the US and Mexico ;)
I would like to propose another consensus. Let us all agree to stop using the term "believe" in and around Climate Change.
Nobody gets to decide if they believe or don't believe in CC. By using the term "believe" people think they need to choose a side like all other belief systems.
You either "understand" or don't understand" Climate Change.
TC @7, yes I realise all that about the movie! I'm sure most people would understand things can't happen that fast or involving super storms taking up half the plant. I was just trying to say rapid change of some sort is possible. I should have been clearer.
Abrupt climate change on wikipedia is an easy to read account of past periods for lay people, and documents periods of several degrees of cooling or warming in a matter of just a few years, and changes in weather systems although not at the speed or scale of the movie. That would still be bad enough for humanity to adapt to on global or even regional scales.
However no doubt the teflon coated president would somehow escape a cooling event, tucked away down in mar a lago.