Sunday
Feb282010
by 
Bishop Hill
Bishop Hill The rot spreads to WG3
Feb 28, 2010 Climate: WG3 The IPCC -gates have so far mainly been a feature of Working Group 2, which looks at the potential impacts of climate change. As Hans von Storch explains in the introduction to a posting by Richard Tol, this is not because the other areas of the IPCC report deserve a clean bill of health.
The WG3 report did not attract the same scrutiny. This could create the impression that WG3 wrote a sound report. That impression would be false. Just as WG2 appears to have systematically overstated the negative impacts of climate change, WG3 appears to have systematically understated the negative impacts of greenhouse gas emission reduction.
Tol's article is a must-read.
Reader Comments (10)
Come on, everyone, give the IPCC a break will you? All the mistakes in WG1 and WG2 happen to overstate recent warming and its negative impacts. All the mistakes in WG3 understate the costs of emissions reduction. But this is just a very unfortunate series of flukes. When will you sceptics ever learn to be fair? (Thanks Frank but I wanted to get there first.)
Richard,
What mistakes in WG1?
There was this thing called Climategate that dealt with that but please don't worry about it.
Richard,
So you don't know of any mistakes in WG1? Didn't think so.
This isn't a high school debate in which point scorig decides the winner. We are all in this together. The fact that AR4 has serious errors and a demonstrated bias is a very serious issue for the world as a whole. We are facing an issue that is potetially catastrophic and we find that we have no good science to help us set policies. The science has been so politicized that it is of no practical use. "Is so" and "Is not" debate tactics will not help in this regard.
No errors in WG1?
You mean except for ice
http://www.worldclimatereport.com/index.php/2010/02/16/another-ipcc-error-antarctic-sea-ice-increase-underestimated-by-50/
"butterflies" and claims of long range modeling accuracy,
http://pielkeclimatesci.wordpress.com/2007/05/18/wg1-ipcc-chapter-1-more-scientifically-erroneous-statements/
and "overconfident" aerosol forcings?
http://www.climatescience.gov/Library/sap/sap5-2/final-report/sap5-2-final-report-all.pdf
"The comparison of individual expert judgments in Figure 5.4 with the summary judgment of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (IPCC, 2007) suggests that the IPCC estimate of uncertainty in total aerosol forcing may be
overconfident."
"This comparison suggests that the uncertainty estimates of aerosol forcing reported in AR4 are tighter than those of many individual experts who were working in the field at about the same time as the AR4 summary was produced."
Hurricanes pending. And we won't even mention paleo...
In most assessments of complex issues, the question of whether or not a mistake has been made can rarely be determined with certainty. But sometimes there are simple mistakes of fact in IPCC reports, and mistakes of this kind can certainly be found in the WGI contribution to AR4 no less than in the WGII and WGIII contributions.
For example, the detailed table of projected regional precipitation changes in WGI Chapter 11, Table 11.1 defines the boundaries of the "TIB" [Tibetan Plateau] region as "30N, 50E to 75N, 100E" (p. 855, left column). It appears that the latitude and longitude coordinates have been inadvertently transposed. The 75N parallel and the 100E line of longitude are nowhere near the Tibetan plateau: the former extends far north of the Arctic Circle and the latter runs east of Tehran, nearly 3000 km from the western edge of the Tibetan plateau.
The text of the same chapter states that "The percentage JJA [June-July-August] change in [projected precipitation by] 2100 under the A1B scenario for southern Australia has an inter-quartile range of -26% to -7% ..." (p. 900). This conflicts with the data in Table 11.1, which gives this interquartile range as -20% to -4%. It appears that the numbers in the text have been taken not from Table 11.1 but from the southern Australian data in Supplementary Table S.11.1, which shows the range of BIAS in the simulated precipitation between the various models, not the range of change in projected precipitation in the 21st century.
Errors of this kind may seem of little importance, but they impair the value of the IPCC reports as reference sources.
Sorry, it's the 50E not the 100E line that runs east of Tehran. But the IPCC did give 50E as the western boundary of the Tibetan Plateau, and this runs nearly 3000 kms west of the western edge of the Plateau.
TAG,
You may not think this is about point-scoring, and that we're all in this together, but the band of AGW supporters don't share your view. They believe we're only all in this together if everyone agrees with them.
As for point-scoring, they get win, place, and show:
(Bill McKibben): "The best analogy [to "deniers"], I think, is to the O.J. Simpson trial...The Dream Team of lawyers assembled for Simpson’s defense had a problem: it was pretty clear their guy was guilty. [...] So [Simpson’s legal team] decided to attack the process, arguing that it put Simpson’s guilt in doubt, and doubt, of course, was all they needed."
Or:
"People who fail to tackle climate change are acting like an Austrian man who locked his daughter in a cellar for 24 years, an Anglican bishop has said."
These are nasty people pushing a nasty agenda of eco-socialism based on flawed and crooked science.
In an imperfect, politicised and media-driven world, I think point-scoring has its place.
In 2010 does this still sound credible -
"We recognise IPCC as the world’s most reliable source of information on climate change and its causes, and we endorse its method of achieving this consensus".
Quoted from the 2001 Royal Society initiated joint statement by sixteen national Science Academies.
How