2010-11-03 16:07:01Scientific Guide to Climate Skepticism: UPDATED, FEEDBACK STILL WELCOME
John Cook


Not long ago, Scott Mandia asked if he could distribute the Scientific Guide to the Skeptic's Handbook to science teachers. I suggested a better option would be to use a more general guide, targeted more at climate skepticism in general rather than Jo Nova's booklet. So the last few weeks, I've been working on the Guide (hence I've been a bit distracted and not as active here on the forum, sorry about that). Can I ask that you all have a good hard look at the Guide and post any feedback or suggestions on how to improve it? The next step after it's been through the Author Forum peer-review process is we're going to send it to a bunch of scientists for feedback with the hope that they'll put their names to the 2nd page of the document before emailing the PDF to science teachers. So please be as harsh and critical as possible in your feedback - I imagine this document will generate a lot of opposition in skeptic circles so its good to be as bullet proof as possible. Here's the download:

The Scientific Guide to Climate Skepticism v3

UPDATE 4 Nov: Thanks for the feedback below, have updated incorporating your comments:

The Scientific Guide to Climate Skepticism v3b

UPDATE 7 Nov: More feedback, thank again to all, latest version is now:

The Scientific Guide to Climate Skepticism v4

UPDATE 8 Nov: Revamped design based on Wendy's feedback, sexy new summer/winter graph from David Karoly, misc textual changes, filling in all the gaps in the design - this is close to finished and should be okay to send to scientists:

The Scientific Guide to Climate Skepticism v5



2010-11-03 21:12:32
Rob Painting
John, Page 3 - "Measurements of the type of carbon found in the atmosphere and in corals show that fossil fuel burning is dramatically raising levels of carbon......."

As this is being distributed to science teachers, I presume the target audience is students?. If so, maybe the explanation should be more explicit, i.e. fossil fuels =such as coal and oil, contain carbon. When burnt the carbon combines with oxygen in the atmosphere to form carbon dioxide (yada,yada).

We often assume the average person knows more about these things than they actually do, and it's flows better if you point this out right off the bat.

Page 4 - "Humans are adding a net 17(?) tonnes of CO2 into the air per year" .

The "billion" is missing from the graphics too.

Page 5- This “CO2 lag” means temperature affects the amount of CO2 in the air . So warming causes more CO2 and more CO2 causes warming. Put these two together and you get positive feedback

The typically naive interpretation of that will be "runaway warming!". Maybe a sentence to indicate otherwise?.

I'll have another look in the morning. Oh, great work by the way!.

2010-11-04 01:02:03


Hi John,

great work and I'm already looking forward to some collaborative effort to get this translated into German once it's considered ready for publication!

Some small things I noticed while reading it:

Page 2 - How do we kno we're causing the CO2 building in the atmosphere?
Should "build-up" or "accumulation" be used instead of "building"?

Page 9 - CO2 isn't spelled the same way each time it is used in the top-left paragraph

Page 9 - Oceans are absorbing much of the CO2 in the air, a process known as ocean acidification.
Is the process of CO2-absorbtion "known as" ocean acidification or is it "leading to" it? The way the sentence currently reads makes it sound as if these are synonyms which isn't how I've understood this so far (and I may well be wrong!).

Page 10 - The pattern of warming show the tell-tale signatures of an increased greenhouse effect.
Either "The pattern..shows" or "The patterns....show" (unless "pattern" is one of few words which only exist as plural....)


2010-11-04 07:43:19


A few minor points

On page 7, the figure shows just land, ocean and atmosphere; no melting ice as claimed in the text.

Fingerprint #3: it shows that heat comes from above, not that it's due to GHG. I know what you mean, but as it stands now may be confusing.

Fingerprint #5: the quote is not from ref. 24, unless i missed it :)

Climategate: I'm not sure I would talk about it. It is not about the science and it probably will be forgotten relatively soon (optimistic mode: ON),

I know it's boring, but you should renumber the references.

2010-11-04 18:44:44Thanks for the feedback so far
John Cook


I've uploaded a new version with the above comments incorporated:

The Scientific Guide to Climate Skepticism v3b

More feedback still welcome. Will hand it over to the worst critic of all shortly - not Steve Goddard... not Anthony Watts... my wife Wendy. She has an ultra-conservative father and brothers so she speaks fluent skeptic, should give it a good working over.


2010-11-04 20:05:23Suggestions for improvement


"any data that doesn't fit" => "any data that don't fit" : "data" is a plural noun

"The other half of the picture" => "The missing part of the picture"

"is at it's highest level" => "is at its highest level"

"(commonly known as heat)" => "(commonly known as heat radiation)"

"climate positive feedback" => "climate-positive feedback" : need a hyphen

"hockey stick shape" => "hockey-stick shape" : need a hyphen

"which now reach levels" => "which have now reached levels"

 "assuming a long-term trend by comparing single years" => "asserting a long-term trend on the basis of selected end-point years"

Human Fingerprint #4: Something not quite right: You say that "Warm is defined as the top 10%." But then how can the number of warm nights be increasing? It's always 36. Please clarify. Also, it would help to spell out what, in the graph, the reader is supposed to see: To someone not used to reading graphs, the warm-days and warm-nights graphs look pretty much the same.

Climate feedback: You should acknowledge that not all feedbacks are positive. This is hinted at, with the yellow arrows illustrating the sunlight reflecting off the clouds, but should be made explicit to avoid accusations of "misleading by omission".

"who rely on the fresh water supplied each year by glacial melt" => "who currently rely on the fresh water consistently supplied by glacial melt"

"skeptical of human caused global warming" => "skeptical of human-caused global warming" : need hyphen. (This also shows up again on the last page: "case for human caused global warming".)

"Consensus of evidence": I really don't like this phrase, because the term "consensus" refers to an agreement in opinion, judgment or sentiment: It doesn't apply to the basis on which this agreement is made. Something like "coherence" or "consistency" would be more appropriate.  "Consensus" means: Most people think this way. "Coherence" means: All the data fit together into a consistent picture.

"There is no single smoking gun but multiple lines of evidence" => "There are multiple lines of evidence"

"The facts about climate change are essential for understanding the world around us, and to make informed decisions about the future." As a matter of style, this is could be improved by imposing some kind of parallel structure: either two gerunds (for understanding, for making) or two infinitives (to understand, to make). Or maybe just skip the "for understanding the world around us"? This isn't a unit in a general-science curriculum, aimed at general education: We're trying to make a point.

2010-11-04 21:40:40Thanks Neal
John Cook


Very specific, have made most of your corrections and updated the file.

But does climate-positive and hockey-stick need to be hyphenated?

And I must admit, I know it's not gramatically correct but I like "consensus of evidence". I noticed Ove Hoegh-Guldberg & John Bruno borrowed it in an op-ed they wrote for a major newspaper so it's a pet phrase of mine.

2010-11-04 22:21:13


The general rule is that when the combination create an adjective, a hyphen is recommended.

Hence, "Jill hit Jack over the head with a hockey stick" doesn't need a hyphen, but "Jill hit Jack over the head with a hockey-stick shape" does.

Of course, this can get complicated: "Jill hit Jack over the head with a hockey-stick-shaped plastic bat" probably needs 2 hyphens.

(After all these illustrations, I hope that Jack has health-care insurance and Jill has a good lawyer.)

2010-11-04 22:42:56
Rob Painting

Tsk, tsk Neal, all that violent imagery. Whatever would a skeptic think?.

Hey John, are you a ventriloquist?. I noticed you didn't move your lips during your interview with Gareth at Hot Topic. 

2010-11-05 00:42:47Pages 7 and 10
James Wight


Good work John, it’s a pretty concise overview of the argument.

I do have some suggestions for how to improve page 7. As it stands I think you are leaving yourself open to accusations of cherry-picking.

Firstly, the graph of ocean heat content only goes up to 2003, so you could be accused of trying to “hide” the relatively flat trend of the last few years. I recommend you use this one from NODC.

Secondly, the paper you reference to support the claim that temperatures have risen since 1998 is now a couple of years old. That paper examined the trend from 1998-2007, not 1998-2010. The latter is still a warming trend but a slower one (+0.07degC/decade in NCDC, for example). I know this is still within the bounds of variability during the “modern global warming era”, but contrarians might not see it that way. Better to admit that 2006-2009 were not as warm as 2005, but point out that we were in the lowest solar minimum of a century, which we are now coming out of.

Also, from memory I think the warmest 12 months were actually August 2009 to July 2010, in both GISS and NCDC.

On page 10: “a few suggestive quotes were seized upon, claiming global warming was all just a conspiracy.” Sorry, the quotes claimed global warming was a conspiracy? Also, in the same paragraph you say “independent investigations” then “independently investigated”, which is a bit repetitive.

2010-11-05 03:22:23comments
Dana Nuccitelli

A few comments - I'm referencing the PDF page numbers, not the numbers at the bottom of the page.

Page 4 - "Plants breathe in".  Breath is the noun, breathe is the verb.

On Page 4 I'd also add after the comment that 'we're adding 17 billion tonnes of CO2 into the air per year', that most of the rest ends up on the oceans.  Otherwise it's a bit confusing that you previously said we send 29 billion tonnes into the atmosphere but only 17 billion tonnes are added - I'd wonder about this discrepancy.

And in the figure caption at the bottom of page 4, the reference to scleorsponges rather came out of the blue.  The figure points out the data from sclerosponges, but not from corals.  It would probably be a bit less confusing if you re-worded the caption to read "Changes in d13C...from corals and schlerosponges" because the comparison doesn't seem to be the point of the figure - as far as I can tell, they're just 2 different sources of d13C data.

On Page 5 I like the way you handled the CO2 temperature lag issue.  Nicely done.  I'd suggest moving the "Example of a Positive Feedback" figure below the "Put these two together and you get a positive feedback" sentence so that it doesn't break up the sentence/paragraph.  It would flow better at the end of the paragraph.

For Human Fingerprint #2, I'd suggest using more up-to-date data than 1996.  For example, Chen et al. (2007) has the spectral data from 1970 to 2006 (figure here as well).  Otherwise you could get 'skeptics' saying you stopped in 1996 because that's when the planet stopped warming.

On Page 6 in the first figure caption, the 2 in CO2 should be a subscript - all the rest are.  In the caption of the second figure I would state which color is which data (i.e. "Law Dome (green)...").

On Page 7 it might be good to specify that Hadley data omits the Arctic rather than just saying it doesn't cover the whole globe.  Otherwise the reader is left wondering which parts are omitted and why they leave out the fastest warming regions.  They could check the footnote, but most won't.  In the ensuing figure I would also specify you're using GISS data.  Again it's in the footnote, but I would suggest putting it in the figure or caption to make it clear, since you were just talking about Hadley data in the previous paragraph.

On Page 8, add hyphens such that it reads "well-placed" and "poorly-sited" weather stations.  It would be nice to add a figure showing the 'good site' and 'bad site' data and satellites to surface stations, but it's understandable you left them out in order to fit everything on one page.

Page 9 - good analogy with the forest fires.  That's my personal favorite in response to the 'climate changed naturally in the past' too.  Bit of a typo - "Positive feedbacks take any temperature change and amplify it" or "any temperature changes and amplify them".

Page 10 - The most quoted email is Phil Jones' "hide the decline".  The use of the term "proxies" comes out of the blue.  This could confuse readers unfamiliar with the term.  I'd suggest adding a sentence explaining that tree ring widths give us information about temperatures.  Change to "it is not conspiratorial scheming, but a technical discussion of..." and add a hypen to "readily-available".  The term "Climategate" at the end of this section comes out of the blue.  If you're going to use the term, I suggest using it toward the beginning.  For Human Fingerprint #6, it's not just the stratosphere that's cooling, but the whole upper atmosphere.  You could change to "the stratosphere and higher layers" or something similar, if you want to keep the stratosphere figure.

Human Fingerprint #7 - it would be nice to explain why the greenhouse effect has more impact on winter temperatures.

You might consider moving the last page before the references - otherwise people might miss it.

Overall an excellent guide.

2010-11-05 22:44:34
Glenn Tamblyn



Firstly some general comments and questions about purpose, tone and style and what the story arc is. These refer to Vers 3.

Who is your target audience? Is this a resource for Science Teachers to use for themselves, to work through with their students or to distribute to their students for them to use on their own? This has a big bearing on the technical level of the document.

Is this targeting an audience who may already be influenced by Scepticism and for whom you are seeking to rebut that? Or Climate Scepticism 'virgins'?

What are you trying to achieve with this. Are you trying to put forward information wrt the full arc of what we need to consider wrt AGW.
1. What is AGW and is it real?
2. How serious might it be?
3. What do we need to do about it?
4. How urgent is it?

Which parts of this are you trying to address?

Next, if it is predominantly step 1, what is the starting point? This goes back to the target audience question. You jump into the evidence for AGW. What if the audience doesn't even understand what the GH Effect actually is - they have heard the name but don't understand it?

Next, Story Arc. Begining, Middle and End. A common aspect of good communication is, tell them what you are going to say, say it, then show them that you said it. If you like, Executive Summary, Body & Conclusion.

Does this tell the reader why the document exists, what its purpose is?

Although SkS began and is still largely defined around rebuttal of sceptic arguments I think it has grown into a stronger platform for advocacy about Climate Change. Consider some of the discussions on the threads about Communicating Science, about not mentioning your opponents points as this locks it into peoples minds. Should you even include a section on Shoot The Messenger at all? Cover the science but ignore the debate.

Now some specifics about individual points.

Human Fingerprints. Perhaps add a caption at the bottom, something like "All these changes have been Directly Observed". Not just the more modulated language like "body of evidence" and "we observe". Stronger stuff as well.

Human Fingerprint #2 Harries et al. This graph says enough to someone who knows what they are looking at, Science Teachers perhaps. But to a less knowledgable audience it isn't as strong. Brightness Temp vs Wavenumber isn't as strong as say W/M^2/micron vs Wavelength - a more understandable presentation to an average science student. Could you contact the authors of the paper and get the same graph in those units.

Also, very powerful, particularly with a teacher to explain it, would be a graph of the OLR Spectrum, with emission temp curves superimposed, again in W/M^2/micron vs Wavelength. Hopefully comprehensible to a student, with the GH Effect right there on the page. Once they understand what they are looking at, the big hole in the CO2 absorption region is pretty blatant. And it might let you add something about emission from TOA vs the surface, opening the possibility for a teacher to discuss the mechanism of the GH effect, not just the evidence for it, in the process possibly opening other subject areas that can whack sceptic arguments.

Human Fingerprint #3 - Ocean Warming. The graph is pretty clear cut but units like 10^21 Joules don't convey much to most people. One calc I have used in the past, its visceral if rather emotive, is to relate this to the Hiroshima Bomb - 6.5 * 10^13 Joules. That is 2.5 bombs per second since 1970.

Then spell out loudly that what most people call 'the temperature' is the atmospheric temperature.

Maybe also spell out that the graphs for ocean temps are only the top 700M. Average ocean depth is 3800 and some warming is occurring deeper as well.

Next, with the 'bad stations' argument. Before jumping from this to Satellites, perhaps interpose how most of the temp record is oceans, not affected by stations. Always trying to draw peoples focus away from the local & parochial view to look more globally.

Human Fingerprint #5 While correct, this is rather confusing without first introducing what Downwelling Longwave Radiation is and why it is important - here is evidence for the GH Effect, before we move on to evidence for the Enhanced GH Effect. Again presenting evidence of a phenomenon that the sceptics don't talk about, undermining their credibility - "They didn't tell us this stuff". The more we can highlight what thy don't say, without actually saying so, the better. But first people need to understand what DLR is and what its significance is.

Shooting the Messenger. Should this be here at all. If you can convey that the shooting is unjustified, maybe, but if mentioning this at all tends to support peoples perception of it, maybe not.

Impacts of Global Warming. Perhaps add a reference to the fact that all our major food crops evolved and were bred by us in the stable conditions of the last 10,000 years, since we first domesticated plants and animals. We have never tried to grow our main crops in a world this much warmer. Also possibly a reference to rates of change, that these are perhaps as large a factor in the impacts as the absolute magnitude of the change.

The Consensus. Is there a way to include that the consensus includes a wide range of disciplines. A common portrail of 'Climate Scientists' is of ill informed nerds, living in a bubble isolated from 'the rest of science' Emphasise the huge range of sciences involved.

Key areas not covered - I don't know if this is where you want to limit this:

Time Lags. Why we haven't seen the full impact of what we have done so far and what this means for the future

Urgency. Because of the time lags and the drawdown time to remove CO2 in the future (mentioning that removing CO2 from the atmosphere will cause CO2 in the oceans to be rereleased might get peoples attention), we need to act now to avoid the problems of accumulation and lags in the future - we can't wait to see what the future will be like because by then it is too late to fix it.

Hope some of this is useful



2010-11-05 23:56:43Update from Mandia


My student have v.3 but not v.3b.  I have given them one week to answer the following questions as extra credit on their final exam.

1)      Are there any areas (text or illustrations) that are confusing?


2)      Which points in the document did you personally relate to the most?  Why?


3)      Are there any topics here that you think are not very important?  Why?


4)      Are there any words anywhere that you think a junior high or high school student may not know?  List them.


5)      Which illustration is best and why?  Least favorable and why?


6)      Are there any topics you would like to see that are missing?  Why should that topic be there?


7)      Are there any points you don’t agree with? If so, why?


8)      Which of the human fingerprints was most convincing?  Why?


9)      Which of the human fingerprints was least convincing?  Why?


10)  Which of the skeptical arguments did you find most persuasive?  Why?


11)  Are there convincing skeptical arguments you have heard or read that we did not include?  Describe.

Here are a few comments I have from v.3:

Pg. 1: what you *might* observe is cherry...

Pg. 2 and anywhere else: in the US it is tons and not tonnes

Pg. 3: Fingerprint #2: do not assume that students will know how to interpret any graph.  For this one I would add a line in the caption that states "negative values means less outgoing heat"

Pg. 4: Define aerosols

Pg. 4: ...the major drivers of *long-term* climate change...

Pg. 4: from these effects *shows*

Pg. 5: it requires *three* (spell out numbers less than ten)

Pg. 5: scientists use techniques *such as* (instead of like)

Pg. 7: Positive feedbacks take any temperatire chnage and *amplify* them.  *Feedbacks* are why our climate....

Pg. 7: Fingerprint #5: Graphic makes it appear that there has been no change in downwelling IR in North America

Pg. 8: To determine if there was any wrong-doing, a number of independent groups from England and the United States have investigated the....

Pg. 9: ...is limited and *is* quickly overwhelmed...

Pg. 9: Global wamring is likely to disrupt *water* supplies through.....

Pg. 9: Fingerpting #7: This is because the greenhouse effect has a greater influence during winter.

Pg. 10:  There is a great line from Dr. Bickmore's (BYU) consensus video that would fit here.  97 out of 100 meand 1 out of 33.  Would you buy chewing gum if the commercial for that gum stated "1 out of every 33 dentists surveyed recommends chewing this gum."  essentially. That is what the skeptics are telling you to do.

Pg. 10: The pattern of wamring *shows* the tell-tale...


As always a huge thank you to John Cook and to you folks who are spending your valuable time on this project.  You are heroes in my book.

2010-11-06 06:57:08Answering Glenn's general questions
John Cook


Thanks to all for a whole lot more very useful specific comments. I haven't had a chance to update the document with the latest batch but will shortly. But Glenn brings up some useful general questions which I think are worth looking at even at this late stage.

Who is your target audience?

Originally, Scott Mandia (aka ProfMandia above) approached me about distributing the 'Scientific Guide to the Skeptics Handbook' to science teachers. I suggested a better option would be to produce a more general version hence here we are. Scott, feel free to correct me here but I assume the target audience is primarily the teachers themselves, arming them with counter arguments in case they're confronted with skeptic arguments. There's also the possibility that they would distribute this to the students so while the teachers are the primary audience, they should also be understandable to high school students.

Is this targeting an audience who may already be influenced by Scepticism and for whom you are seeking to rebut that? Or Climate Scepticism 'virgins'?

Good questions. I guess either - it's for teachers who will inevitably get asked questions in class so this gives them an education on how skepticism works.

What are you trying to achieve with this?

There are two things I want to communicate - two take-home messages:

  1. Climate skepticism doesn't consider the full body of evidence but cherry picks
  2. The full body of evidence finds multiple lines of evidence for AGW

So I establish those two points on page 1 then continually reinforce them throughout the Guide. I don't really stop to explain the basics of the greenhouse effect, or solutions or urgency. There's only so much you can say in a small guide and by trying to say everything, you risk dilluting your central message. So I stuck to those two key points. 

But I welcome thoughts on what else should be in there. The Guide is 15 pages long - am thinking of adding one more page to take it to a nice neat 16 (multiples of 4 are more convenient for printing).

Should you even include a section on Shoot The Messenger at all?

I don't think we can ignore climategate. A year on, it's the #1 argument on SkS over the last month. It's still huge and will only get worse with Republicans taking the house. So it needs to be addressed, to try to look the way will only magnify the issue.

However, I think we can turn it into a strength - Climategate is really about the campaign to sow doubt about the science - that needs to be the narrative. I'm working on a blog post about climategate that reframes the issue and once that's done, I may borrow from some of the language to strengthen the language on the climategate page.

Anyway, there has been great specific feedback on the Guide but these general questions are very useful too. Welcome discussion on the general tone and what else should go in the book.

2010-11-06 08:33:48another page
Dana Nuccitelli
If you wanted to add another page, you could do one on climate sensitivity.  Maybe add it before the impacts page.  Tough topic to condense into one page though.
2010-11-06 18:53:19
Glenn Tamblyn


A follow-on from Scot's comments

Hopefully when he gets some feedback from his students he can shoot it our way.

And picking up on the following point "do not assume that students will know how to interpret any graph" This goes to the heart of something important when our communication moves beyond the battleground of the blogosphere out into the wider world. We can easily fall into the trap of seeing the to-and-fro off the internet as what defines the contest. It isn't. It is simply a small side pocket of the larger battle where we happen to be engaged. Overwhelming, most people don't read Climate Blogs. Their lives are about other things. And most people see Science as a weird, alien world, divorced from their lives.

Sometimes I wish there was a way to take the graph of the planets OLR spectrum and sear an understanding of what it really means into peoples souls. It encapsulates what the GH Effect is. And if you REALLY get that, then AGW is just a small Delta from that. But for most people a graph of numbers is meaningless. What's a wavenumber? What's a Watt? What's a micron? What's Electromagnetic Radiation?

To highlight the gulf between those who have a general technical education and the majority who don't, a couple of personal anecdotes.

In my town several years ago there were protests against the installing of a mobile phone tower. The modern world encroaching, we were going to be irradiated etc. At a town meeting, after some argy bargy, someone pointed out that we were already surronded by EM emissions all the time from radio, TV etc, a mobile phone tower wasn't going to change this much. At which point a woman in her 30's piped back - 'But I can turn my TV Off."!!

My elderly mother, who had a limited education when she was young. recently had an operation for catteracts. As she came out from under the anaesthetic she had a wonderful light show, probably an after effect of the anaesthetic. Sitting over coffee a couple of days later talking about it she came out with the fact that she thought sight happened because of light coming out of our eyes!!

We may be shocked by this lack of understanding but these are our fellow citizens on the planet. They vote and are concerned about their future and we need their acceptance of what needs to be done to move forward. And that's before we consider how we bring people like your average chinese rural farmer who thinks Rhino horn will help his erectile disfunction and would like satellite TV and a rice cooker. Then maybe a wide screen TV like everyone else.

So perhaps there are two messages to be conveyed. Here is the truth. And here is how these 'sceptics' have conned you. When someone tells you what you want to hear, you believe them. But if you then discover you have been conned by them, your anger can be a powerful force. Maybe its time to go on the offensive and show people how they are being conned. If you can go for a sceptic's jugular, do so. Politely but brutally.

Which obviously goes way beyond the scope of John's handbook for teachers. But something to bear in mind more generally when looking at what our approach is. Someone said we need a movement. That is a damn good idea. A movement of all those who have the technical understanding to 'get it', seeking to communicate it to all those around us. And maybe we need to be in peoples faces. A Lot. And use the tactics of the enemy. Psychology, Communications, Framing the Question. And probably very much an underground movement that slips under their guard.

In this fight, communication is the only game in town. Very professional communication. The science is there. The answers are there. Now it is just about mobilisation. And as Bill McKibben said recently. We have tried nice. It didn't work.

Simple reality. This is War. And the stakes are very, very high. Our grandchildren.

2010-11-07 01:27:25Version 4 now uploaded
John Cook


Okay, have updated the Guide with all the "micro-changes" from Neal, James, Dana, Glenn & Scott's students. Eg - all the specific textual changes, not any big sweeping changes like adding new pages or changing the tone of the Guide (which I haven't ruled out yet but am admittedly relucant to do because I always take the path of least resistance). Here's the latest version:

The Scientific Guide to Climate Skepticism v4

A few comments:

I've changed the title from 'climate skepticism' to 'global warming skepticism'. The term 'climate skepticism' is ridiculous and invites criticism - noone is skeptical about climate or that climate changes. Technically it should be 'anthropogenic global warming skepticism' or 'catastrophic anthro...', you get the picture. But brevity must be considered to some degree.

James, I've got GISS saying the 12 mth average from June 2009 to May 2010 is 0.669°C. The anomaly from Aug 2009 to July 2010 is 0.657°C.

James, LOL, just reread my sentence "a number of independent investigations from England and the United States have independently investigated the 'climategate' emails". Lucky you caught that bad writing before I showed the Guide to Wendy, who would've jumped all over it (no, I'm not using you guys to perfect the Guide so I'll look better to my wife :-).

Dana, re using Chen 2007 for Fingerprint #2, I just wonder if that graph is even harder to understand than Harries 2001. It is a bit technical:

Increased greenhouse effect -  models vs observations

Glenn, my Murphy 2009 graph of ocean heat is actually an estimate of heat down to 3000 metres. I added your bit about the Hiroshima bomb - powerful stuff.

Scott, should I be converting all my numbers of metric tonnes to U.S. tons?

Again, thanks to all for your invaluable feedback.

2010-11-07 01:48:04General Comments


The Guide as I had envisoned it would be for high school and middle school teachers to give them a quick summary of how we know humans are driving climate along with why the arguments against it are incorrect or misleading.  It would be written at a level that middle and high school students could understand if these teachers distributed the document.

You would be very surprised to know that most science teachers and many college science professors are not aware of even this most basic information in our guide.

The bad guys (JoNova/Heartland and Fraser Institute) have already disctributed their propaganda so this is the "good guys" response.  In more conservative states and districts some teachers may not be allowed to use this guide and there could be battles looming ahead.

I think our best chance at changing the mentality in the US is to focus our energy on the politically unwashed - our kids.  They do not pay taxes yet so they are not influenced by the rhetoric.  If we can get them to understand the science before they enter the workforce, they will be more likely to do what is necessary to solve the problem.

It is no longer good enough to think "if we build it they will come".  We must bring it to them.  Bring the water to the horse so to speak.  John has been very good at this push vs. pull strategy and this is just anohter new attempt.

I have connections with the Board of the Science Teachers Association of New York State (STANYS) so this state will be the pilot.  Assuming they approve of the distribution, we can then look to other states and point to what New York is doing.

I hope this helps.

2010-11-07 05:01:11Chen graph
Dana Nuccitelli
Yes, the Chen graph may be a bit harder to understand.  It would be nice to at least mention that the data has been update to 2006 though.
2010-11-07 10:10:54Tons

No.  Keep the metrics but just use the American spelling for "tons".
2010-11-07 15:19:05Merely switching tone to ton
John Cook

Is that kosher though? A metric tonne = 1.1 "U.S. Tonnes" so to be 10% out invites criticism
2010-11-07 23:04:35Version 4; and urgency
James Wight

I have just looked at version 4 and I notice you’ve left in the out-of-date OHC graph and the reference to “Waiting for global cooling” on page 7 of the document (labeled page 5). I still think you need to include more recent data.

Also, I noticed the text on that page overlaps with the graph title “Earth’s Total Heat Content anomaly”.

About time lags and urgency – I think it would be worth adding an extra page on this. Otherwise it is all too easy for readers to say “well, okay, maybe there is a lot of evidence for AGW, but we’ll let the scientists debate that, and if it starts to get really bad then maybe we should do something about it…” The consequences of a “wait and see” policy need to be made clear. I suppose there is a danger of getting a bit too political here, but you don’t have to specifically say we must act (which involves a value judgement), just that the problem is urgent if we intend to do anything about it (which follows from the science). You don’t need to talk about specific solutions at all.
2010-11-07 23:33:40Tons


Maybe use both?  Use metric tonnes but in parentheses use the equivalent US tons?  It is important to use metrics with kids so that they understand that is the "language" of science.  I agree that we cannot leave an Achilles Heel of any kind for the deniers.

2010-11-07 23:39:11Urgency


I agree with James but this is the area where there is debate so we need to be careful.  I like the following quote:

What's the use of having developed a science well enough to make predictions if, in the end, all we're willing to do is stand around and wait for them to come true?"
-- Nobel Laureate Sherwood Rowland (referring then to ozone depletion)

Maybe we can use acid rain, DDT, and ozone depletion as examples where science showed that humans were causing a problem but we reacted in enough time to solve it before it got too bad?

Although this is a pet peeve of mine (scientists are not alarming enough nor political enough) I am unsure if this topic fits in with the rest of the guide.  Although I would love to see this in there, I am inclined to say keep it out.

2010-11-07 23:40:48One more thought

Maybe instead we just show what the world looked like the last time CO2 levels were this high?  Sea level rise alone in this example would demand immediate action.
2010-11-08 10:38:36Front Page of the LA Times


This project is mentioned in a front page story of today's Los Angeles Times.


2010-11-08 15:31:46Comment
Robert Way

So when will this be disseminated?
2010-11-08 15:55:50
Rob Painting
Scott Mandia - cool. The war on superstition begins!. 
2010-11-08 16:12:47Media attention re climate scientists fight back
John Cook


I find it fascinating that the story of climate scientists fighting back is getting such traction. I listened to a journalist last Monday night saying how newspaper editors lost interest with climate change stories, it was boring, old news, a ratings killer. But this new narrative - angry climate scientists fighting back - that is getting major attention.

Anyway, getting back on topic, I've updated the Guide and I think it's ready for the next stage - sending to scientists for feedback before disseminating:

The Scientific Guide to Climate Skepticism v5

So to answer Robert's question, this will get disseminated as soon as we get feedback from the scientists. I'm keen to send this off asap. Hopefully the scientists won't be too slow in responding.

James, re the OHC graph, sometimes you have to balance the pros and cons of different graphs/messages. In the OHC case, the Murphy 2009 graph is just fantastic - says so much in a very simple visual graphic. There is no such data going to 2010. In fact, when I was corresponding with Dan Murphy who sent me his data, we were emailing back and forth about this and I asked him if it was possible for him to extend the data to 2010. He stopped emailing after I asked him that. Perhaps I pushed the friendship just a little too far - I've since learnt to be very cautious when asking favours from busy climate scientists!

Similarly, my reference to that 'global warming since 1998' paper which is a few years old is perfectly valid - their argument holds whether the analysis was done then or now. And their conclusion is reaffirmed by the GISS data that extends to the last month.

You also have to balance being scientifically bullet proof in order to protect yourself from skeptic attacks versus presenting a simple message accessible to a general public. To be absolutely bullet proof, you have to add so many disclaimers, clauses, technical definitions, etc - that your message will be dilluted and lost on a general audience. So sometimes you just have to go with the simpler message, thus opening yourself to criticism. At least I've got the website to flesh out the details further.

Scott, re tons vs tonnes, I think it would complicate the page unnecessarily to have both. One or the other, I think, or at most a tiny message at the bottom of the page (1 metric tonne is equivalent to 1.1 U.S. tons). I've gone with tonnes for now.

2010-11-09 14:36:52Comment
Robert Way

I've forwarded this on to:

Dr. Lev Tarasov
Dr. Andre Viau
Dr. Joel Finnis

Two climatologists and a climate modeller. I know one will be responding tomorrow and another hopefully soon after so this should get pretty thoroughly vetted...
2010-11-09 17:21:42Thanks Robert, look forward to their thoughts
John Cook

BTW, Scott has decided to wait one week before sending it to all his climate scientist contacts as he's still getting feedback from his students. I will probably tinker with it over the next week also (I'm mulling over putting some tiny animals on the 'Indicators of Warming' infographic, can't help myself). So anyone feel free to send any extra suggestions over the next week.
2010-11-10 12:58:37Scholastic & Chamber of Commerce


Here is another reason why our Guide is so important:


We now have some more friends to help us get this out.

2010-11-11 12:35:46Cover Letter


We need to begin to think about the cover letter that will be sent to the scientists to ask them if they would endorse the Guide.  I figured we would introduce the project and than ask for their comments/signatures.

To introduce the Guide I used John's comments from the top of this thread and then my comments toward the bottom:

A few weeks ago I asked John Cook if I could distribute the Scientific Guide to the Skeptic’s Handbook to science teachers. He suggested a better option would be to use a more general guide, targeted more at climate skepticism in general rather than Jo Nova’s booklet. The past two weeks, John Cook and a group of very talented authors from his site have been working on The Scientific Guide to Climate Skepticism. We are in the 5th revision and are now sending it to scientists across the world for their comments and hopefully, their endorsements.

The Guide is for high school and middle school teachers to give them a quick summary of how we know humans are driving climate along with why the arguments against it are incorrect or misleading. It is written at a level that middle and high school students can understand if these teachers choose to distribute the document.  Of course, the Guide could be distributed to any person who is looking for an easy-to-read primer on the human fingerprints of global warming.

Surprisingly, many science teachers and even some college science professors are not aware of even the most basic information in our Guide.

We ask that you read this Guide and consider having your name appear in our contributor/commenter section.  Your name would lend great credibility to this endeavor.

This is just a draft and I appreciate any re-writes to make it a stronger letter.  BTW, John Abraham, Ray Weymann, and I have been speaking to some people with large resources.  We may be able to get this to many more people and more quickly than I had originally anticipated.  We also are riding a media wave so it is likely that this Guide could be advertised in major papers.  An ABC News reporter I spoke with has already shown interest in writing about this project.

2010-11-11 13:03:39Feedback on letter
John Cook


Can I suggest removing mention of Jo Nova - the whole point of doing the general guide was that I didn't want her getting more than her 15 minutes of undeserved fame (I almost regret writing the original guide in the first place because of the attention it gave her but I guess it got us to this place so it all works out for the best). How about:

A few weeks ago I discussed with John Cook the idea of distributing a basic guide to global warming skepticism to science teachers. The past two weeks, John Cook and a group of very talented authors from his site have been working on The Scientific Guide to Global Warming Skepticism. We are in the 6th revision and are now sending it to scientists across the world for their comments and hopefully, their endorsements.

Note the title is now the guide to Global Warming Skepticism, not Climate Skepticism. And by the time I get your students' feedback on the weekend and make all those changes, it will be version 6 - the final version to go out to the scientists.

We ask that you read this Guide, offer any suggestions to improve the content and consider having your name appear in our contributor/commenter section.  Your name would lend great credibility to this endeavor.

Perhaps ask for feedback here - I guess it's implied if they're listed as a commenter but perhaps ask explicitly.

I think it's very exciting, all the opportunities to distribute the Guide even more widely than originally anticipated - not to mention all the media attention you've attracted over the last week (which is a fascinating insight into the human appetite for conflict, heroes and villains). Of course now I'm feeling a little more pressure about any potential errors in the guide. Your idea of distributing it to members of Congress had me freaking out a little. :-) Fortunately we have that safety net of scientists checking it out. And after reading the news of the Chamber of Commerce using Scholastic to indoctrinate kids, the anger sponges away any anxiety.

2010-11-11 13:43:35Let me know if you'd like me to credit you in the Guide
John Cook


To everyone who posted comments here, let me know if you'd like me to include your name in the 2nd page of the document. If you're a scientist, include your institution and I'll put you in the list of scientists who've commented.

Note: if this Guide is to be as distributed as widely as Scott seems to be indicating, I'm anticipating there will be some very intense, negative backlash from skeptics. You know the rule, the intensity of opposition is directly proportional to how effective you are. So consider this when deciding whether you want to put your name on it.

2010-11-11 19:17:40
Glenn Tamblyn

In for a Penny, In for a Pound. Put my name on John. Although my affiliation won't carry much weight. Coffee anyone?
2010-11-11 22:00:24# of Signers


There has been a question off this forum in email conversation if the Guide is stronger with fewer signatories (say 10ish) or more.

My personal feeling is the more the better which gives the Guide and thus the science in it a stronger "consensus" especially if there are many varied disciplined signers.


2010-11-12 03:56:27more probably better
Dana Nuccitelli

I tend to agree that the more contributors listed, the stronger it looks.

I wouldn't mind being added, unless it's agreed that fewer names are preferable.

Dana Nuccitelli - Environmental Scientist, Tetra Tech, Inc.

2010-11-12 08:34:34

I don't think it is necessary to extend the list as much as possible. There are already 6 reputable scientists as a gurantee of quality, maybe a few more names will be enough. I see a difference between, say, a public statement to be released to the media and this short guide. Having tens of signatures might give the impression of a sort of political statement, an impression that we don't want to give expecially when its target are schools.
On the contrary, short post-publication comments would be welcome.

Should you decide to have more signatures, you can add mine as
Prof. Riccardo Reitano
Department of Physics and Astronomy
University of Catania (Italy)

2010-11-12 10:02:46Comment
Robert Way

My feeling on the whole signatures thing is that having 10-15 isn't bad but over that amount might be a bit much...
2010-11-15 02:54:09My Students Respond

21 of my students reviewed the Guide.  These students are non-science majors and most are fresh out of high school and very few follow any news.  Here is a summary:


1)  A majority of students said they preferred the pictures over the graphs.  For example, the most often complimented pictures were the cherry tree, the Indicators of a Warming World, and the carbon cycle.  The least favorite by far was the isotope image in Fingerprint #1 followed by the hockey sticks.  Unfortunately, the image in #1 must be changed because almost every student complained about it.  If any of you can think of non-graphical images to replace any of the graphs, we should consider doing so.


2)  When asked which Fingerprints were the favorite, none stood out but most were complimented.  However, Fingerprint #1 was singled out by many students as the least favorite/most confusing for both text and illustration.  Is there a way to simply this text by removing the isotope discussion with a simpler explanation?  Maybe:


There are different types of carbon in the air known as carbon isotopes.  Nature emits one type of carbon isotope while burning fossil fuels emits a different type.  Measurements show that the fossil fuel-type of carbon is rapidly increasing while that of the natural type is fairly constant.  Therefore, the increase in carbon dioxide in the air is directly linked to human emissions.


3)  Words that students think might be confusing to school children include: sclerosponge, isotope, proxies, decadal, anomaly, coherence, El Nino.


4)  Some students thought that we should define weather vs. climate and mention that a cold winter does not discount global warming.  Winters will still be cold seasons but they will become less cold and last for shorter periods as the world warms.


5)  Students asked why the focus was only on CO2 and not other GHGs.


6)  Students think tree ring growth needs to be explained on pg. 8.


7)  Some thought that the Shooting the Messenger page was unnecessary but that is likely due to the fact that they do not follow the news.  I suggest keeping it in because it appears to be the biggest skeptic argument and it will resonate with people who have heard about it.  Students are not the only audience now.


8)  A few students confused “positive feedback” to mean good.  Perhaps we need to add:  Positive and negative does not mean good vs. bad.  Positive feedbacks strengthen the climate changes already underway while negative feedbacks suppress (weaken) the climate changes already underway.


9) Several students thought that the graphic in fingerprint #2 was a bad idea because the data ends in 1996.  Is there something newer we can use?


10)  I think something we might add to pg. 2 is that the weight of CO2 emitted to the air each day is comparable to the weight of 8,000 Gulf of Mexico oil spills each day.  See:


11)  Pg. 2 the image shows nature emitting 771 while the text states absorbing 770.  Then we say this is “balanced”.  We need to change to 771.





I have changed my mind about the number of signatories.  I think having more may not be a bonus.  10-15 is good.  We need diversity in the list including:


1)  Scientists from different disciplines especially those in fields related to the information in the Guide
2)  International scientists
3)  Female scientists