IPCC Scientist's Nobel Moment: No developing catastrophe nor human activity cause | Hacker News Reader

IPCC Scientist's Nobel Moment: No developing catastrophe nor human activity cause

online.wsj.com

10 pointsgibsonf121 comments

The conclusion as I understand it is: Since reversing climate change is a hard and expensive process, we should give up trying.

"...I see neither the developing catastrophe nor the smoking gun proving that human activity is to blame for most of the warming we see..."

I'm confused....is the conclusion that we should listen to the one dissenting scientist in ten thousand because he gets a few column inches in the Wall Street Journal?

From a scientific standpoint, we shouldn't listen to one scientist any more than we should listen to a thousand of them. Science is about models and reproducible experiments. Not consensus.

Since this was an op-ed and not a description of a model or an experiment, it's about opinion and politics. I believe the conclusion is that some scientists have different opinions and political views than others, right?

Indeed. 99.99% of the world's scientists, based on careful interpretation of many thousands of peer-reviewed studies, agree that global warming is real, and is caused by human activity.

A vanishingly small handful of scientists happen to disagree with this assessment, based mostly upon their opinion and politics.

Repeat after me: model and reproducible experiment, model and reproducible experiment. All science is provisional and must maintain falsifiability for it to be called science.

Statements about how many scientists believe any thing, from phrenology to aether to gravity, is an interesting observation about the current opinions and politics of those who practice science. It is not science itself.

Thousands of peer-reviewed studies (that means models and experiments) have come to the conclusion that global warming is real, and is caused by human activity.

It may be "interesting" that one guy in Alabama disagrees with the overwhelming scientific consensus on this issue, but it's certainly no more interesting than the members of the flat earth society, or my great uncle Fred, who happens to think that radio waves cause cancer.

You said you were confused about the point of the article. I believe I have explained the purpose of op-eds.

Now I believe you are trying get into a discussion about global warming. My suggestion is that if you are still confused, the topic of your confusion should be "why op-eds about my pet causes bother my sensibilities"

I'm afraid I do not have an answer to that question. I'm not trying to be a flip with you, it just seems your initial post was not as clear as it could have been. I'm sure there are lots of folks who would like to argue global warming with you. I am not one of them.

The only "pet cause" that I have, is to debunk the notion that outsider opinions in science should be given consideration because they are in the minority.

I'm sorry if you were confused by my use of rhetoric. However, it gave you a chance to lecture me on the properties of science ("models and experiments"), so perhaps it wasn't time wasted?

Peer-reviewed studies come to concrete conclusions such as "Ice volume in antarctica has decreased an estimated X% in the last X years." or "CO2 levels in the atmosphere have increased X ppm in the atmosphere at Mauna Loa observatory." rather than sweeping statements such as "global warming is real".

There are admittedly some real cranks among the global warming skeptics, but I thought the arguments discussed in this article were intelligent, rational, and well-spoken.

Intelligent and rational? Really? He makes three coherent arguments:

1) Overzealous people have exaggerated/confused global warming with recent local weather phenomena, and this is wrong.

2) Predicting climate change is hard and our climate models are inaccurate.

3) Given the choice between reducing carbon emissions, and feeding starving children, we should favor feeding starving children.

Arguments 1 is a straw man -- true, but irrelevant to the question of whether global warming is real and caused by humans.

Argument 2 is also true, but is a red herring -- it fails to address the volumes of science that would suggest that, despite the difficulty of the problem, we have good reason to believe that there is a problem.

Argument 3 relies on a false dichotomy -- there isn't a clear and necessary relationship between increased spending on climate change, and decreased spending on (say) HIV vaccines or mosquito nets or starving children.

(sigh)

It is not true that there is overwhelming scientific consensus about the probability of climate change. While I would agree that most scientists think that it is most likely that "global warming is real", there is a great deal of uncertainty among even the worlds leading climate scientists about the probability of global warming.

A few years ago I ran a betting game among students and faculty in the MIT climate program, the idea was to develop some feeling for the 'community consensus' of the likelyhood of global warming. The conclusion: ~71% chance of global warming over the next century.

http://www.sethjohn.com/PAOC%20CFM/slide1.html

http://www.sciencemag.org/cgi/content/full/306/5702/1686

"That hypothesis was tested by analyzing 928 abstracts, published in refereed scientific journals between 1993 and 2003, and listed in the ISI database with the keywords "climate change" (9).

The 928 papers were divided into six categories: explicit endorsement of the consensus position, evaluation of impacts, mitigation proposals, methods, paleoclimate analysis, and rejection of the consensus position. Of all the papers, 75% fell into the first three categories, either explicitly or implicitly accepting the consensus view; 25% dealt with methods or paleoclimate, taking no position on current anthropogenic climate change. Remarkably, none of the papers disagreed with the consensus position.

Admittedly, authors evaluating impacts, developing methods, or studying paleoclimatic change might believe that current climate change is natural. However, none of these papers argued that point.

This analysis shows that scientists publishing in the peer-reviewed literature agree with IPCC, the National Academy of Sciences, and the public statements of their professional societies. Politicians, economists, journalists, and others may have the impression of confusion, disagreement, or discord among climate scientists, but that impression is incorrect."

There are really a couple of separate issues here. First, it is important to distinguish between the general scientific agreement about past climate changes and the greater confusion about the probability of future climate changes. One of the main reasons why there is such broad agreement among the community is that scientists have tended to focus on the answerable questions such as "has the earth been getting warmer over the last X years" rather than the thornier question of "what caused the earth to get warmer" and "will the earth continue to get warmer." Very few scientific papers have been written that make predictions on the question of future climate.

It is also important to remember that while there is generally scientific consensus that global warming is "probably" happening (whatever that means!) or that it is "probably" caused by humans, there is a great deal of uncertaintly about exactly what the probabilities are. If you could get all scientists to agree that there was about a 71% chance that the next century would be warmer, does that count as "scientific consensus that climate change is likely"?

Read the article.

What caused the earth to get warmer?

"the National Academy of Sciences report, Climate Change Science: An Analysis of Some Key Questions, begins: "Greenhouse gases are accumulating in Earth's atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise" [p. 1 in (5)]. The report explicitly asks whether the IPCC assessment is a fair summary of professional scientific thinking, and answers yes: "The IPCC's conclusion that most of the observed warming of the last 50 years is likely to have been due to the increase in greenhouse gas concentrations accurately reflects the current thinking of the scientific community on this issue" [p. 3 in (5)]."

Will it continue?

Directly from the IPCC report:

http://www.grida.no/climate/ipcc_tar/wg1/035.htm#temperature

"Global mean temperature continues to increase for hundreds of years at a rate of a few tenths of a degree per century after concentrations of CO2 have been stabilised, due to long time-scales in the ocean....If greenhouse gas concentrations were stabilised (even at present levels), sea level would nonetheless continue to rise for hundreds of years....The loss of a substantial fraction of the total glacier mass is likely. Areas that are currently marginally glaciated are most likely to become ice-free."

Both the National Academy of Sciences and the IPCC are essentially political organizations (in the sense that their purpose is to inform policy, I don't mean to suggest that they are partisan) and what they say should not be conflated with the scientific literature on climate change.

Scientists are working very hard to understand past and future climate change, but it is an incredibly complex problem. (For analogy, can political scientists predict who will be elected president in 2012?...it's possible to make some good guesses but there are a lot of factors and it's hard to know what will happen.)

Sure, there is general agreement on some points and organizations such as the IPCC are doing a noble job of trying to synthesize the mountains of complex science into a few simple statements, but I think you are drastically oversiplifying the case when you say that

"99.99% of the world's scientists, based on careful interpretation of many thousands of peer-reviewed studies, agree that global warming is real, and is caused by human activity. A vanishingly small handful of scientists happen to disagree with this assessment, based mostly upon their opinion and politics."

Yes, it's a complicated problem, but there's a heck of a lot more than just "general agreement."

When it comes to the two central questions (is global warming real? is it caused by human activity?) the situation is just overwhelming: very nearly all of the published literature is in agreement that the answer to both questions is "yes".

There is certainly less unity on other questions related to climate change, but it's misleading to suggest that there's any significant scientific disagreement on the issue.

The economic argument from the AGW advocates (Stern report) is that we should spend $100 today to avoid spending $95 (or less) in the future.

Why or how is it going to get cheaper to deal with if we procrastinate?

The "cures" are frightfully expensive. The mitigations and costs are less so. (The "cures" do get less expensive as technology develops, but Stern didn't include that factor.)

Read the Stern report. Notice the discount rate. (Stern does argue that it's appropriate to spend $100 now to avoid spending $95 in the future.)

Or, maybe you want to argue that Stern is wrong about the economics.

I think that he is, but not in a way that strengthens his conclusion that we should apply the cures now. (Yup - he's an AGW advocate and a commonly cited source for the economic argument.)

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