(excerpts)

Consider, for instance, Figure 10-1. Here is the previous version (left) and the new version (right):

That it was redrawn to look better is fine. The problem is the data represented in the two figures are not the same. The diamond (representing an estimate published in the last five years) between 2 and 2.5 degrees has shifted almost to 3 degrees. Two points previously at 2.5 degrees have shifted left to 2.2 degrees. A new diamond was added at 3 degrees. A circle at three degrees and about 5%, which previously stood out, has vanished. The diamond at the far right side has shifted even farther right, going from just under five to just to under 5.5 while also dropping quite a bit. The diamond at the bottom has fallen as well, being lower by nearly one full point.

Not a single one of these changes was disclosed. We can verify them, however, by examining the tables provided for both figures. I’ve previously displayed the table for the first figure:

Here is the new version of the table (found in the IPCC Supplementary Material):

Every difference I highlighted in the figures can be confirmed in these tables. More differences can be found as well. For instance, we can see the estimate from Nordhaus 1994a was changed from -4.8 (-30.0 to 0.0) to -1.9 (median), -3.6 (mean) [-21 to 0.0]. This change is neither disclosed nor explained. Also unexplained is why only both the median and mean values are shown yet only the median value is displayed in the graph.

More here: http://hiizuru.wordpress.com/2014/10/17/undisclosed-changes-in-the-ipcc-ar5-report/

But I imagine there may be others. It’s interesting because the section the changes I discuss are in was actually added after the last round of reviews (while the section immediately after it was rewritten). That means the material never underwent external review before being released in the “Final Draft,” and then it was secretly changed again before the official version.

If the IPCC will allow this to happen in one spot, who knows what else they might have allowed?