This repeats some buried comments but I think it's worthwhile: I'm not a climate scientist, but in my experience the absolute most reliable, most time-efficient way to learn about climate change is the IPCC reports. I wonder if there is anything written in any other field that compares:
Specifically, if you are short on time, read the 'Summaries for Policymakers', written at the level and attention spans of non-technical politicians. They are quite readable and as I wrote in another post, if they can understand it, so can you. :) (The longer reports are fascinating, if you have an interest in science and want to get lost in something.)
As I understand it the reports are prepared by a global team of hundreds of scientists, and reviewed by thousands more.[1] (Seriously, has anything like that existed in any other field?) They are meant to cover the breath of climate science and the reports also are meticulous about the language of probabilities.
Spend a little time reading them and it will save you the time of reading 99% of what's written elsewhere, and you'll be much better informed.
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EDIT:
[1] Review process: http://www.ipcc.ch/activities/activities.shtml (scroll down to "The AR5 Writing and Review Process") -- for example, one report had over 50,000 comments on two drafts from >600 experts.
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EDIT 2: Website interface help.
Can you believe this needs to be written, and for HN readers? I had JavaScript off which makes the site usable (if not pretty). With JavaScript on, apparantly the UX concept is 'Easter eggs':
There are 4 images arranged horizontally at the top; these are report covers (with text too small to read even if you knew they were clickable). If you click a report cover then the section beneath it changes to display a description of and links to that report.
All that work making the reports accessible to the world, hamstrung by web design.
A couple years back I read the IPCC reports trying to find out if global warming was real or not. I noticed the Vostok ice core data in the earlier reports showed the temperature rose first and then the CO2 rose. Likewise, the temperature fell first and then the CO2 fell later on. They fixed this little inconvenient data problem in the later reports.
> ... This statement does not tell the whole story. The initial changes in temperature during this period are explained by changes in the Earth’s orbit around the sun, which affects the amount of seasonal sunlight reaching the Earth’s surface. In the case of warming, the lag between temperature and CO2 is explained as follows: as ocean temperatures rise, oceans release CO2 into the atmosphere. In turn, this release amplifies the warming trend, leading to yet more CO2 being released. In other words, increasing CO2 levels become both the cause and effect of further warming. This positive feedback is necessary to trigger the shifts between glacials and interglacials as the effect of orbital changes is too weak to cause such variation.
In the Vostok data the temperature falls first and then the CO2 falls. If the CO2 released amplified the increased warming trend then why would the temperature suddenly reverse absent a CO2 drop?
BTW, I am really really disappointed in the quality of all the replies. It's mostly ad hominem and hand-waving. This is the one reply that's not but it doesn't explain the behavior of the drop in temperature.
Thus to sum it up:
Increased temperature causes gas to become less soluble in the ocean, thus leading to increased CO2. Decreased temperature causes CO2 to become more soluble in the ocean thus leading to decreased CO2. This data shows then that CO2 increases are not enough to cause warming all by themselves or to prevent cooling all by themselves.
Obviously a very large amount of CO2 in the atmosphere will lead to warming (e.g Venus's atmosphere is 96% CO2) but we're many orders of magnitude off from that (0.04% CO2).
So we are left with what I like to call a Listerine argument: Listerine has been selling more over the past century, Listerine prevents tooth decay, thus Listerine is the cause of the improvement in dental health over the past century. Thus we should put Listerine in the water and implement a global tax so everyone can have Listerine.
You might be interested in the opinion of Richard Muller:
In 2010, I watched one of his talks in which he had very uncharitable things to say about some groups of climate scientists and why he did not consider them trustworthy [1].
At about 34:28 of the video, you can hear him say the following:
This is why I'm now leading a study to redo all this in a totally transparent way.
He did [2].
What was his conclusion? Global warming is real, and in all likelihood the culprit is indeed CO2.
How did he come to that conclusion? Because it's the only proposed mechanism for global warming that actually fits the data on the 250y scale.
This is not an inconvenient data problem. That the ends of past ice ages were not caused by a rising atmospheric carbon dioxide concentration but instead caused it with some lag does not at all proof that a rising atmospheric carbon dioxide concentration can not cause rising atmospheric temperatures.
For example - completely made up - a change in the orbit of the earth could cause rising temperatures and therefore the end of an ice age. This could then free carbon dioxide trapped in or under the now melting snow and ice and in turn this change in the composition of the atmosphere could additionally contribute to the rising temperatures.
I'm sure the IPCC has flaws, like every other human institution (but what else do we have to work with?), but the original reports came out in 1990. Also, every data set ever produced has inconsitencies.
I don't feel that one inconsistency from 25 years ago, which might have a valid explanation or might be validly considered inconsequential, undermines the IPCC reports' credibility.
This is hardly unexpected. As water warms, the solubility of various gases decreases. I.e., if you exogenously warm up the ocean, it will release CO2 and other trace gases into the atmosphere. I'm pretty sure you could get the same pattern for Argon and other (non-greenouse) trace gases.
So, that's an interesting phenomenom, albeit one with possible explanations (that others have provided), but I'd like to volley a question back to you: have you performed the same experiments that Arrhenious[1] performed in 1896, that has been reproduced thousands of times before, and come up with a different result? (ie, that CO2 doesn't create a greenhouse effect).
Ugh. This is exactly the type of poorly-informed response you generally get when people attempt to "read the data" for themselves with little to no understanding of the science behind it. Seems to be a lot of that going around HN today.
Well, for one, that their uneducated skim through the IPCC report found a mistake which thousands of qualified scientists had missed, one so fundamental that it undermines all of the rest of the work in the report and the conclusions it leads to.
The scientists say so, therefore the commenter is wrong? This still doesn't explain why the above is wrong. Attacking the premises of an argument is sound logic, and should be welcome. Ad hominem arguments should be called out.
It's exacerbated when it's less someone reading it for themselves, than reading it in a blog post by someone who's motivated to try to strip context and mislead about results.
Your comment reminds me how the Catholic Church treated the Bible during the Middle Ages (environmentalism runs so parallel to religion it's uncanny).
The clergy would not let lay people read the Bible themselves, claiming there are "poorly-informed responses you get when people attempt to read the scripture for themselves with little to no understanding of the theology behind it."
"Just trust us," they said, "we will interpret it for you and tell you how to live accordingly."
This is a summary of research in those peer-reviewed journals, the summary being far better reviewed (by hundreds and thousands, as described) than the individual articles.
I don't know about other HN readers, but I don't have time or expertise to keep up on individual articles. I doubt many climate scientists have the expertise in all those different fields.
I'm not afraid of looking at the source.
Many times the "summaries" get distorted.
Statements like "provide some evidence for" gets translated into "this proves". Popular press often does this.
The actual raw data and original article and independent confirmation is the gold standard for science.
I've chased down many stories reporting "proof" in many fields and , after examining the actual article, found that it actually said "well, this might be some evidence for possibly maybe supporting something".
This is a hazard in MANY fields.
Many people know this.
We Hacker News readers ran in to this a couple of days ago.
Somebody said "Fasting helps in cancer therapy" and listed some science papers. It was voted up.
The actual papers DID NOT SAY THAT. They said "this small sample might provide some evidence but more study needs to be done".
These are separate things and careful readers can discern this.
Appeal to Authority or to a Mob or to Fashion is NOT science.
> Statements like "provide some evidence" for gets translated into "this proves".
For what it's worth, the IPCC reports are very, very careful about this. They have a chart (though it can be hard to find) of exactly what confidence/probability is meant by each phrasing.
EDIT: for example, from the Sythesis Summary for Policymakers report:
The following terms have been used to indicate the assessed likelihood of an outcome or a result: virtually certain 99–100% probability, very likely 90–100%, likely 66–100%, about as likely as not 33–66%, unlikely 0–33%, very unlikely 0–10%, exceptionally unlikely 0–1%. Additional terms (extremely
likely 95–100%, more likely than not >50–100%, more unlikely than likely 0–<50%, extremely unlikely 0–5%) may also be used when appropriate.
What prestige science journal article says "virtually certain" that man is primary cause of global warming?
What phrasing in the results section makes you feel that it is "near proof" ?
I'm not asking for "it is likely or probable". I'll buy that. I want solid proof ... or , uh "almost proof".
Proofs don't exist in sciences concerned with the physical world. For proofs to work in the real world, you'd need certainty that you have recognised and correctly measured every variable that could affect the outcome of an observation/experiment.
The last philosophy of science that allowed proofs was positivism. For the natural sciences, it has been replaced by critical rationalism (https://en.wikipedia.org/wiki/Critical_rationalism). CR gave a solution to the proof problem: While positive proofs like in your quote don't work, you can still falsify a theory. By continuously falsifying theory after theory about an observed outcome, something resembling truth remains. Truth, but never certainty. Hence the talk about likelihood and probability.
> I'm curious. Gravity has not been proven to attract two masses, for instance?
Correct. That's why it's called the theory of gravity :) You would need Laplace's demon (https://en.wikipedia.org/wiki/Laplace's_demon) for a proof. "Proof" means absolute certainty. You only find that in math, not in the physical world.
As he already said, science doesn't do proofs; proof is something for Math, science does evidence, nothing is ever proven. Asking a scientist for proof merely shows you don't know what science is and thus aren't capable of using it to make decisions.
> Is there any evidence that two masses don't attract ?
The answer to that question does not in any way proof the existence of gravity.
I don't mean to offend, but if you honestly ask these types of questions, I doubt you are able to evaluate the quality of original papers dealing with climate research.
Am I to understand that you'll only "bet the climate" if it's a sure thing? I'm curious to know if all important decisions you make are backed only by "virtually certain" odds that the outcome of your decision will be as you predicted.
Not trolling, honestly. I really want to better understand this mindset.
Science once labeled gay as a mental disease.
Science once said that neutrinos have no mass.
Science once thought that the universe was the Milky Way only.
"Virtual certainty" may not always be "settled science".
I do think we should curtail pollution; regardless of the scientific certainty on man as primary cause of global warming.
> Science once thought that the universe was the Milky Way only.
No it didn't.
All of those are made up facts that bear no resemblance to reality. Science doesn't say or think things, it merely shows the current state of evidence for theories and when new evidence comes along, wrong theories are disproven. That's what science does, it disproves ideas.
A scientist likely once theorized that gay was a mental disease, the process of science disproved that theory; ditto for everything else you said. You're confusing some scientists bad theories for science itself, they are entirely different things.
Yes really. That scientists had such debates proves my point, not yours. Science doesn't make absolute claims, it posits positions based on evidence and changes those positions when the evidence changes. Sadly, you're clearly not intelligent enough to understand the distinction.
Only the second and fourth paragraph of this response are "important". The rest is an attempt at clarification of my personal viewpoint. I'm doing my absolute best to not offend people on a very touchy subject - but I know it is inevitable to do so. For that, I apologize for holding a different opinion but ask that you read the entire response to understand the reasoning behind my position.
[Paragraph the second] The declassification of homosexuality as a mental disorder had more to do with harassment of the APA for several years leading up to 1973 by advocate groups than it does scientific consensus. Scientists are afraid to speak on the issue due to harassment and the possibility of losing their jobs due to said advocate groups. Even so much as trying to conduct studies on SOCE would get you harassment nowadays if the public was aware.
If we are to consider reproduction and the continuation of a species to be what is "normal" for a species (ie. the goal of a species is to produce a generation to succeed it to avoid extinction) then homosexuality is a disorder. Homosexuals cannot reproduce naturally and only through scientific advances can they choose to have a surrogate mother or a sperm donor to have a child: which is from a heterosexual process.
[Paragraph the fourth] The issue that arises of classifying it as a mental disorder is the stigma people attach to people with mental disorders. This stigma can be harmful to people and thus should be avoided. Regardless of scientific accuracy - I approve of any effort to treat people more humanely and if that means not considering a deviation from the norm to be a disorder, than so be it. I would like to point out that not all mental disorders have equivalent social stigma attached. OCD and insomnia don't tend to get someone harassed - while being anti-social or autistic is more likely to get someone harassed.
The definition of "mental disorder" is a mental condition that negatively impacts the person with the disorder. It's not clear (due to poorly conducted studies [0]) whether homosexuality is a disorder or if societal pressures are the cause of an increased number of suicides and depression. Until the social stigma goes away, I don't think we can find an answer on this. My intuition tells me that the increased amount of stress/depression/suicide are all strongly correlated with social stigma and that in more progressive and accepting regions these negative feelings are more rare. But my intuition and science don't always agree, so I've learned to not trust my intuition.
My personal views are closely related to Havelock Ellis [1].
>He proposed that being “exclusively homosexual” is to be deviant because the person is a member of a minority and therefore statistically unusual, but that society should accept that deviations from the "normal" were harmless, and maybe even valuable. Ellis believed that psychological problems arose not from homosexual acts alone, but from when someone "psychologically harms himself by fearfully limiting his own sex behavior.
TFL;DFR: It doesn't matter if it is or isn't. What matters is that society works to remove the stigma attached and treat each other humanely.
A layperson named Steve McIntyre did just that, after reading the IPCC's 3rd Assessment Report and seeing the prominently featured "Hockey Stick" based on a paper by Mann et al., and wondering, hmm... perhaps this study is reproducible?
The rabbit hole that McIntyre and his colleagues have found themselves in over the last 10 years has, in my view, demonstrated the value of hacker-types taking an interest in climate science.
"Of crucial importance here: the data for the bottom panel of Figure 6 is from a folder called CENSORED on Mann’s FTP site. He did this very experiment himself and discovered that the PCs lose their hockeystick shape when the Graybill-Idso series are removed. In so doing he discovered that the hockey stick is not a global pattern, it is driven by a flawed group of US proxies that experts do not consider valid as climate indicators. But he did not disclose this fatal weakness of his results, and it only came to light because of Stephen McIntyre’s laborious efforts."
IIRC, despite the criticsim, the 'hockey stick' study and its author were proven right. Lots of criticism doesn't make it wrong, especially in politicized debates.
You should just stop with this line of thinking. You have to understand the scientific context and the limits of the data to learn anything. (Source: I know several contributors to the IPCC AR5 report, and I try to have the proper respect for their expertise.)
Great, so you're capable of writing highly parallel cluster-scale code in C that does intensive precision numerical analysis? Most choose vectorized FORTRAN or a combination of C++ and CUDA, but hey, knock yourself out.
CERN has a 3700 core supercomputer to crunch through this kind of data. You can rent that on Amazon for about $800 an hour, so I guess you're good to go.
Sorry to be so harsh here. While there's always desirable amount of "constructive naivety" necessary to try the impossible, you need to recognize that there's considerable amounts of expertise required to process and analyze data of this complexity at scale.
This is not like a movie where six minutes of furious typing can solve any problem.
The gist of this argument is that the IPCC's members, the schools that employ them, the governments of their constituent nations, the FAO, the UN, the mainstream news media, and all administrative and custodial staff of all of these organizations are perpetrating a conspiracy to push carbon taxes on the world. Presuming the absurd scale implied herein doesn't beggar belief, the fact that the combined power of all these people has proved insufficient in bringing 'the plan' to reality ought to.
> the United Nations would be funded by such taxes
The UN does not tax anyone. They are funded by governments, which are funded by taxes.
1) By your theory, there is a confict of interest for the UN as long as anyone involved pays taxes, which covers every issue on the planet (and some in orbit, on Mars, etc.).
2) One major tax-paying industry, which has exceptional influence in government, is oil and gas. If the UN has a conflict of interest in favor of an industry, one with a long track record, I don't think I can find a better example.
You're basically saying anything funded by government that might impact economics, and thus revenues, is biased. Right..
You do realize that you can be against taxing say, income and profits, but be for taxing carbon? I think quite a few economists would agree that you tax things that you want less of. A simplified carbon tax could be a boon to business.
> You're basically saying anything funded by government that might impact economics, and thus revenues, is biased. Right.
While I don't see the now-deleted comment you're replying to, I do feel there is validity to the viewpoint that studies funded by the government can be biased in much the same way as studies funded by private companies. Government is not magically above tainting research with predisposition and prejudice.
The deleted comment said that the IPCC wants to introduce climate taxes; that the IPCC would get funded by those taxes, and thus there is a conflict of interest.
In the absence of any other context, saying "X has a conflict of interest because Y" implies "and therefore X is unlikely to be believed." Yes, presumably the UN does have a conflict of interest here. However, as Cholantesh points out, the size of the IPCC makes it unlikely that conflict is a major factor in affecting the interpretation of data (I am agnostic as to how likely the CoI is to affect the actual policy recommendations). Just pointing out the conflict, without any additional interpretation, is dodgy enough that it's reasonable to assume it's motivated by a conspiracy theory.
http://www.ipcc.ch/
Specifically, if you are short on time, read the 'Summaries for Policymakers', written at the level and attention spans of non-technical politicians. They are quite readable and as I wrote in another post, if they can understand it, so can you. :) (The longer reports are fascinating, if you have an interest in science and want to get lost in something.)
As I understand it the reports are prepared by a global team of hundreds of scientists, and reviewed by thousands more.[1] (Seriously, has anything like that existed in any other field?) They are meant to cover the breath of climate science and the reports also are meticulous about the language of probabilities.
Spend a little time reading them and it will save you the time of reading 99% of what's written elsewhere, and you'll be much better informed.
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EDIT:
[1] Review process: http://www.ipcc.ch/activities/activities.shtml (scroll down to "The AR5 Writing and Review Process") -- for example, one report had over 50,000 comments on two drafts from >600 experts.
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EDIT 2: Website interface help.
Can you believe this needs to be written, and for HN readers? I had JavaScript off which makes the site usable (if not pretty). With JavaScript on, apparantly the UX concept is 'Easter eggs':
There are 4 images arranged horizontally at the top; these are report covers (with text too small to read even if you knew they were clickable). If you click a report cover then the section beneath it changes to display a description of and links to that report.
All that work making the reports accessible to the world, hamstrung by web design.