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Comment by tosseraccount | Hacker News Reader

Is there a scorecard for which models have performed well?

The IPCC, probably the best source overall for climate info, has in their reports visualizations showing predictions, and I think historical results, of multiple climate models. (Sorry but I don't have time now to find links and page numbers. Try the Summaries for Policy Makers.)

http://www.ipcc.ch/

Just reading their summaries, which are meticulously prepared and reviewed by hundreds of scientists, will make you more informed than 99.9% of the population, and more than most reading this thread.

None of the models have performed very well. You probably won't find a scorecard because it's embarrassing.

Citation needed.

Probably a long list of ExxonMobil shill sites.

Here's a good one:

http://www.drroyspencer.com/2013/04/global-warming-slowdown-...

44 Climate Models all fighting to out-panic one another, not a single one guessing low enough to predict the actual values for 2012 (when it seems the dataset in question ended)

... and a seemingly more reputable one showing roughly the same thing:

http://phys.org/news/2015-01-peer-reviewed-pocket-calculator...

The first graph on that second link is a bit confusing and seems pretty disingenuous. It has the "observations" region stretching to 2050. The rest of the article seems much more factual and interesting, but why start with something so misleading if your supposed goal is to debunk misleading projections?

I wouldn't call a paper whose lead author is a well-established denier with no scientific training (https://en.wikipedia.org/wiki/Christopher_Monckton,_3rd_Visc...), and which is co-authored by a known practitioner of large-scale scientific fraud for pay (http://rationalwiki.org/wiki/Willie_Soon) particularly reputable.

ad-hominem. Who cares who wrote it, what does it say?

Neither you nor the person you are responding to probably has the requisite qualifications to actually tell …

Judging something like this without relying on outside signals seems rather impossible and pointless if you are not, you know, an actual expert. No matter how much you want to believe you can be one about everything …

Really? You think it doesn't matter that the primary author on a paper about climate science doesn't even have an undergraduate-level education in the subject? That the second one credited has a history of accepting large sums of money to write papers endorsing spurious claims DIRECTLY RELATING to climate change?

Are you going to tell me that every person who has ever written a paper on computer science needs to have a degree in it? While I won't question this guys qualification might be questionable - making a blanket statement that someone must be specifically educated in a subject to write a good paper on it is specious.

How often does it happen that a layman manages to get published in a well-regarded journal? Out of all the papers that laypeople publish anywhere, how many survive scrutiny from experts in the paper's problem domain? And out of those, how many that actively seek to overturn a paradigm succeed?

Based on this metric alone, it is highly unlikely that Monkcton is qualified to discuss climate change, and as it happens, his published work tends to be published by fairly obscure journals whose standards of review are questionable, and when they pass the desks of career climatologists, the result is generally unfavourable to him.

There is a difference between "layman", "well known expert in their field", "so and so with a degree in $field" "well known expert in their field with a masters in $field"

If you read my reply, I don't question the guys qualifications, I was objecting to the blanket statement of "you must have a degree in $field, to be expert" - many papers in technology, are written by people without degrees in that field.

I did read your reply; I'm saying that in the aggregate, a credible paper is unlikely to be written by someone without formal schooling in the relevant field.

Further, technology is applied science - it is not unlikely that one can become an expert through informal and professional practice. Your previous comment was about computer science, which is not necessarily the same thing, and which is closer to mathematics than anything else. Climatology is concerned primarily with physics and chemistry, but also geology and in some cases, paleontology. Most of these fields share little in common with pure maths or engineering. The comparison, then is not totally valid.

The basic training you require to be a competent scientist is hard to come by outside of academia. The actual work of science tends to be done in a laboratory. It's highly, unlikely, then, that someone who has put in the years (often decades) of work in academia to be on par with a hobbyist, whatever that may look like in this context.

A lot of the IPCC lead authors are paid by NGO's (like Greenpeace) with a vested interest in climate alarmism. Do we discount their work too?

Climate science covers a lot of different areas, everything from economics, through hard chemistry and fluid dynamics, to pure statistics. No one person can be an expert on all of this, and no one qualification will make anyone competent in all of them. Experts from related disciplines are perfectly qualified to speak on "their" areas of climate science.

Greenpeace is a non-profit, so they have much less to gain from 'climate alarmism' than the fossil fuel industry does from climate denial.

Monkcton studied classics and received a post-grad diploma in journalism. That's pretty far removed from being a related discipline.

Ad hominem fallacy fallacy: http://laurencetennant.com/bonds/adhominem.html

Pointing out that someone is not trustworthy when considering whether or not to trust their conclusions is not ad-hom.

Attacking a persons 'trustworthiness' instead of dealing with their arguments and evidence is pretty much the dictionary definition of the ad-hominem diversion. It doesn't interest me to learn that he kicks cats or dresses in lingerie and calls himself Marjorie at the weekends. If you believe that he is wrong, then show where and how he is in error.

You're right not to be intersted in whether he kicks cats or not when you're thinking about whether he's honest or not.

But, when thinking about whether he's honest or not being given examples of previous dishonesty is relevant.

Just like the infamous Smathers campaign speech?

http://msgboard.snopes.com/cgi-bin/ultimatebb.cgi?ubb=get_to...

"Are you aware that Claude Pepper is known all over Washington as a shameless extrovert [pervert]? Not only that, but this man is reliably reported to practice nepotism [necrophilia] with his sister-in-law and he has a sister who was once a thespian [lesbian] in wicked New York. Worst of all, it is an established fact that Mr. Pepper, before his marriage, habitually practiced celibacy [???]."

No, because that was actually irrelevant. In this context, Soon's record within the scope of climate research is what's being scrutinized, not his personal life.

If Soon's opponents were attacking his love of Dune or his tendency to eat falafel, there might be an analogue here.

Irrelevant. The technique you used was the same as Smathers, and your intent was the same - to damage someone's reputation by insinuations and smears. It is low behavior.

Smathers' accusations related to issues that had no bearing on Peppers' merit as a political candidate or his ability to carry out his official duties. My 'insinuations' (actually, again, statements of fact) are related to Soon's behaviour within the context of climate science. If you cannot grasp this, you are not qualified to engage in debate. If you do not wish to for whatever reason, it makes it pretty clear that you are not interested in good faith discussion of this issue and are not worth anyone's time in that regard.

A damaging and false insinuation is a damaging and false insinuation, whatever ground it purports to cover. Smathers chose smears that would do the maximum damage to Pepper as a politician, you did the same for Soon as a scientist.

You inspired me to write a thing which will save me a lot of time in the future. Thank you.

http://www.robsheldon.com/tactics-of-crackpot-debate/#4

Actually, it is.

You can't look at someone's financial interest to know whether what they said is true or not. Similarly for any other attribute about them that you don't like.

There are many great thinkers who were gay. We don't invalidate their work because of that.

At best, you need to keep that in mind and take what they said with a grain of salt. Funding gives you a clue about which areas to be more critical about, but just because they have an interest one way or the other doesn't invalidate what they said.

If someone has been found to be a nutjob, you may casually dismiss what they said as a time saving device or because there is low probability what they say has any value to you. But even a nutjob is sometimes right.

> co-authored by a known practitioner of large-scale scientific fraud for pay (http://rationalwiki.org/wiki/Willie_Soon) particularly reputable.

Flagged for libel. It is one thing to argue a position you believe, it is quite another to smear another's character.

It wasn't libel the last time you brought it up and it isn't libel this time. Soon failed to disclose non-trivial amounts of funding that he received from parties who have a vested interest in deriding climate science. Given how often his work has failed to pass muster when scrutinized by climate scientists and skeptics, it is hard to fathom how any of this can amount tosimple incompetence.

The article you linked to is almost comical in its petty malevolence, well beyond the point of self-satire. This kind of character assassination, however reprehensible, is ultimately irrelevant. If you believe Dr. Wei Hock Soon is wrong, then show where and how he is mistaken.

Climate scientists have been doing that for almost 25 years at this point, and Soon's response has pretty much been to complain that he's being bullied and that science is being politicised. I find that to be actually comical, almost as much as the presumption that an intelligent and intellectually honest person could do this for as long as Soon has. And that his association with political and industrial think tanks is a non-sequitur in this regard.

Do read this criticism of Roy Spencer's methods, which to me do not appear credible: http://blog.hotwhopper.com/2014/02/roy-spencers-latest-decei... http://blog.hotwhopper.com/2014/05/roy-spencer-grows-even-we...

Not the most credible looking site, but the graphic seems well cited: http://www.drroyspencer.com/2013/04/global-warming-slowdown-...

Spencer is pretty out there. He's gone on record to say that warming proponents are advancing an argument that will lead to more deaths than the NSDAP's policies did, and is a signatory to the Evangelical Declaration on Climate Change, which suggests that this is largely a matter of faith for him...

He does also maintain one of the satellite records, which does show global warming over the period 1960-2000 (not so much the last 10 years because of the global warming hiatus).

And other records do not show such a hiatus (http://www.skepticalscience.com/global-warming-not-slowing-i...).

Did you even read the article? look at the university of York dataset, which clearly shows the 1960-2000 warming followed by the 2000-2010 hiatus. Note the York dataset is strictly observationally independent of the UAH dataset.

Evidently we were reading different articles,because the author emphatically doesn't concur with your interpetation of the York dataset.

RSS troposphere's hiatus goes back to December 1996 as of May 2015.

Did any models predict the "global warming hiatus" ?

Hans von Storch, professor at the Meteorological Institute of the University of Hamburg discussed this issue in a recent interview with Der Spiegel. He remarked that less than 2% of model runs reproduced the 'pause'.

http://www.spiegel.de/international/world/interview-hans-von...

SPIEGEL: Just since the turn of the millennium, humanity has emitted another 400 billion metric tons of CO2 into the atmosphere, yet temperatures haven't risen in nearly 15 years. What can explain this?

Storch: So far, no one has been able to provide a compelling answer to why climate change seems to be taking a break. We're facing a puzzle. Recent CO2 emissions have actually risen even more steeply than we feared. As a result, according to most climate models, we should have seen temperatures rise by around 0.25 degrees Celsius (0.45 degrees Fahrenheit) over the past 10 years. That hasn't happened. In fact, the increase over the last 15 years was just 0.06 degrees Celsius (0.11 degrees Fahrenheit) -- a value very close to zero. This is a serious scientific problem that the Intergovernmental Panel on Climate Change (IPCC) will have to confront when it presents its next Assessment Report late next year.

SPIEGEL: Do the computer models with which physicists simulate the future climate ever show the sort of long standstill in temperature change that we're observing right now?

Storch: Yes, but only extremely rarely. At my institute, we analyzed how often such a 15-year stagnation in global warming occurred in the simulations. The answer was: in under 2 percent of all the times we ran the simulation. In other words, over 98 percent of forecasts show CO2 emissions as high as we have had in recent years leading to more of a temperature increase.

Confused: this is the hottest year on record worldwide. In what way is this 'taking a break'?

And the ten hottest years have been since 1997?

This makes me think of when financial journalists/broadcasters constantly report that the SPX or the DJIA or the FTSE or whatever are hitting 'all time highs' and it's a really useless piece of information. Investors want to know how much it went up by on the day (and what he trend of the last few days/months has been), the fact that it poked through to a new high level is not important.

Except - temperature! It does actually matter if its 100 or 200 degrees.

Simple: this is exactly what you would expect on a high plateau. Think about it in terms of climbing a mountain with a fairly flat top. For a long time you're moving continuously up-slope, then when you get to the plateau you wander around randomly and frequently find outcroppings that are higher than anything you've encountered before. That doesn't mean you're still climbing, and if we were still climbing at the rate seen from 1980-2000 the "global mean temperature" (which is a thermodynamically meaningless arithmetic average) would be even higher than what we see today.

People who continually beat on extrema (like Denialists who claim that cold weather on the East Coast last winter is somehow proof that AGW isn't happening) are adding noise to the argument, not signal. The physically meaningful number is the heat content of the Earth/ocean system, and there's quite a bit of evidence it is rising, and that a significant portion of that rise is due to human activity.

Apparently, the past models did not, because they did not model the long term interaction of the oceans with the atmosphere, and the current "hiatus" is mostly about the atmosphere temperatures, while most of the warming is currently happening in the oceans.

The more sophisticated current models do match the recent observations if you feed them the past data:

http://www.theguardian.com/environment/2014/sep/09/research-...

I think http://judithcurry.com/2013/10/30/implications-for-climate-m... is a reasonably representative informed article on this.

Depends, overall predictions from the mid 1980's where high and a lot of research has gone into why.

A significant part of the difference disappears if you adjust for CO2 produced vs predicted. Granted, you can argue that the older models needed to account for both, but what we want to validate is predictions of impacts not predictions of fossil fuel use.

It's extremely disingenuous to show a single line as the 'prediction'. There have been plenty of projections that include possible reductions in temperature. As well as a wide range of types of measurements.

PS: You can also do a lot of cherry picking on both sides: http://phys.org/news/2012-04-climate-eerily-accurate.html

Great points. To add a little more detail, predicting the results of greenhouse gasses in the atmosephere is science. Predicting the amount of gasses in the atmosephere requires predicting human economic activity in detail (how much, in what form, etc.), which is impossible, especially on longer timescales (imagine how many investors would love to know how to do that!)

The predictions I've seen, at least in the IPCC reports,[1] show not lines but confidence intervals that widen over time.

[1] https://news.ycombinator.com/item?id=9772353

They've not performed well based on criteria chosen by global warming denialists.

For example, you'd be hard pressed to find a climate scientist making any solid predictions about annual global temperature averages. You will, however, see predictions about decadal averages, and those have borne out.

Borne out? Compared to what? The RSS and UAH 6.0 lower troposphere predictions? What other measurements do we have that don't have uncertainty bands as large as the measurements?

And the zero trend from May 2015 extends back to 1996 for RSS and UAH 6.0.

That "zero trend" is only there if you use annual averages.

Again: use decadal moving averages, and an entirely different picture comes up.

How do you use decadal moving averages from satellite data that has only existed since 1979? You'll get roughly the same trend as the full data set. Even so, the last two decades would still be flat, or very nearly so.

Hint: decades don't have to start with year 10*n+0.

We already know the full data set has a 1.2K/century trend (this is annual trend most commonly used to represent the data). Decadal moving averages aren't going to shed more light than that. We also know that if you just grab the last 19 years and 6 months, or any smaller subset of that, you'll see 0 to negative trends.

Which is why you should not follow along the denialist gambit and grab just those two data points.

But they're the best data we have. They have the widest coverage, the least uncertainty. At nighttime the SST satellites can have over 10C of error due to cloud cover. I've no doubt the earth is warming. My doubt is that measurements with wide confidence intervals should be used over those with low confidence intervals because they tell a more compelling story.

What good is a model if it does not make solid predictions?

Oh, those models do make predictions. Just not the ones the deniers use for straw man arguments.

As someone else shared above:

http://www.skepticalscience.com/lessons-from-past-climate-pr...

the grandfather from 1981 seems to hold up pretty well. simple linear models, very readable paper.

http://www.realclimate.org/index.php/archives/2012/04/evalua...

Yes there is! In fact, this very visualization which you are commenting on is based upon the data produced by NASA Goddard from their climate model by running a historical data prediction, as their contribution to precisely such a comparison/consensus building study sponsored by the IPCC, called the "Coupled Model Intercomparison Project Phase Five". There are links to the sources for all of this in the original article. This information, which I'm sharing with you now, is in the first three paragraphs of endnotes on the actual article.

So.... please don't believe other posters who might come along and try to get you to believe that historical comparisons haven't been performed, or the results haven't been published, or that the IPCC ignored them, or whatever else they might choose to argue today.

Even if there is a model that performs well, how do you account for survivorship bias?

And how accurate are models without a clear understanding of the physical reasons why behind them?

Seems like we should be concentrating on understanding the physical relationships and less on trying to come up with abstract models. It kind of feels like a bunch of astrologists and just picking the one that seems to perform better.

Unless I understand the why, I have a hard time accepting what anyone says.

Anyone can fit a model to the data.

Here are some images that you could review.

https://www.google.com/search?q=1990s+climate+models+versus+...

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