2011-08-16 02:12:37Suggestion for new series "Dodgy Diagrams"
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

 

It ocurred to me that it would be handy to have a pictorial index of dodgy diagrams that skeptics use to make incorrect arguments, where the user could click on a thumbnail of the diagram in question and go to a blog article that briefly explained what is misleading about the diagram, with links to relevant pages at SkS and elsewhere with a more in-dpeth discussion.  This would be especially useful where such diagrams occur in skeptic comments to blog articles, where someone has regurgitated e.g. a Moncktionian slide, as the response would be simply to give them the URL each time it appears.  An example is given below

 


Dodgy Diagrams: IPCC Maximum Residence Time

This diagram has appeared on a number of skeptic websites, purporting to show that the IPCC use an estimate of the atmospheric residence time of carbon dioxide is much greater than the figures given in the peer-reviewed litterature.  The terminology used in the IPCC reports is perhaps a little unclear, however the diagram clearly misrepresents the position of the IPCC.  The relevant paragraph (section 1.2.1 on page 8) of the first IPCC WG1 "Scientific Basis" report is quoted here:

"The turnover time of CO2 in the atmosphere, measured as the ratio of the content to the fluxes through it, is about 4 years.  This means that on average it only takes a few before a CO2 molecule in the atmosphere is taken up by plants or dissolved in the oceans.  This short  timescale must not be confused with the time it takes for the atmospheric CO2 level to adjust to a new equilibrium if sources or sinks change.  This adjustment time, corresponding to the lifetime in Table 1.1 is of the order of 50-200 year, determined mainly by the slow exchange of carbon between surface waters and the deep ocean.  The adjustment time is important for the discussions on global warming potential c.f. Section 2.2.7." Emphasis mine, not the IPCCs.

The definition of "turnover time" given is the same as the definition of residence time commonly used in the peer-reviewed litterature, so the bar for the IPCC in the diagram should be at least 20 times shorter, and is infact shorter than most of the estimates in the peer reviewed litterature.  Clearly the originator of the diagram has confused residence/turnover time with the adjustment time, even though the IPCC clearly and explicitly warned against such a misunderstanding. 

[links to SkS articles etc]

2011-08-16 02:35:11good idea
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

I like the idea.  Plenty of fodder from Monckton for this sort of series.  It's one of those things that we have to find the time to implement, though.

2011-08-16 04:03:30
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

Perhaps we could start by just submitting some blog articles as time permits and then add the pictorial index once there is enough of them to make it worthwhile?

2011-08-16 08:31:47Dodgy Diagrams - great idea and alliterates too!
John Cook

john@skepticalscience...
124.177.173.40
If SkS's three-fold goal is to "find questions, write answers, supply answers", then this idea is a good application of the third point of supplying answers. We've already responded to many dodgy diagrams In misc blog posts but this repackages it in a very accessible manner. Possibly what we could end up with is a picture gallery of dodgy diagrams. The danger is the "backfire effect" where by making all these dodgy diagrams accessible in one place, they end up reinforcing myths. But I think we can alleviate that by the way we structure it. Imagine the Dodgy Diagrams page featuring thumbnails of each dodgy diagram in the left margin, the right margin containing a short, snappy explanation of how it misleads (similar to our one liners). Then follow the link to the blog post which fleshes it out.

I suggest we adopt Dikran's suggestion - write a few blog posts then once we have a few under our belt, add it as a new feature.

Note: I think Doug Mackie already hit the turnover graph - we probably already have plenty of blog posts that could have a Dodgy diagram button applied immediately. If a few blog posts are identified, I could set this up sooner than later and it won't take much programming to set up.

2011-08-17 03:53:33
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

I did the one on the Monckton/Morner/SPPI report graphic that rotated the sea level rise graph to make it look flat.

Another good one would be Monckton's graph where he draws his (mis)interpretation of IPCC global warming projections.  I don't think we've done any posts on that though.

2011-08-17 09:07:09Monckton's IPCC projections
John Cook

john@skepticalscience...
124.177.173.40

That has been done, long ago, a guest post by Alden Griffith:

http://www.skepticalscience.com/How-Monckton-got-his-IPCC-predictions-wrong.html

That was listed on our page of Monckton SkS blog posts too:

http://www.skepticalscience.com/Monckton_Myths_blog.htm

2011-08-19 06:49:01
dana1981
Dana Nuccitelli
dana1981@yahoo...
64.129.227.4

Ah see, there's a good Dodgy Denier post all ready to go.  CBDunkerson actually suggested a similar series in a comment today.