Bart can retire - Part I

Bart Verheggen, owner and operator of My View on Climate Change, aka Our Changing Climate, reports on a study carried out by the Planbureau voor de Leefoomgeving (PBL),aka the Netherlands Environmental Assessment Agency, on the reliability of Working Groups II's report in the AR4. More exactly, the PBL's political masters asked for a specific evaluation of the chapters evaluating probable regional changes. Eli will encourage you to hie over there to read the results, but the general outcome was that the report was reliable, even though they found one additional clunker. What caught Eli's attention was that the PBL took comments from the public. Of the 40 or so that came across the transome, ONLY 3 were relevant, but the PBL provided answers to them all and Rabett Run is pleased to add them to his retirement home.

COMMENT: It has come to my attention that the PBL has opened a website for reporting errors in the IPCC report. It is apparent to me, however, that this website limits the chapters on which the comments must be about and allows for no other comments or questions. This unfortunately impeded the open and honest debate about the IPCC report that many seek. Therefore I take this opportunity to write to you in the hope that my comments will be taken into account by you and your colleagues.

I will keep my questions and comments brief, acceptingthe risk that they may not in all respects be expressed perfectly scientifically or technically. For this I apologize. If my questions are not clear, I am happy to explain them further.

My questions / observations are as follows:

1. The effect of the flood of human-produced CO2 on the (alleged) (enhanced) greenhouse effect.

The IPCC assumes a significant effect of CO2 on climate. Although CO2 is a greenhouse gas, the influence of water vapor in the atmosphere is much greater, given the much larger amount of water vapor in the atmosphere than CO2. The influence of CO2 on a (possible) temperature increase is only about 3% of the total impact. I would like to understand why the IPCC ascribes a major influence to anthropogenic CO2.

2. The IPCC reports the report was "peer-reviewed". P

I am curious to hear from you, how the comments of "peers" were handled . It could be (I blame no one!) that only the positive reactions were considered and the negative ones were ignored. In that case it would still be peer-reviewd "despite the negative comments not being considered.

Note: In my time I did TNO tests of devices. Some were unequivocally rejected. But some of those who submitted devices made a point in their advertising that their products were "TNO-tested"!! Linguistically that was correct, of course, but it twisted the meaning. Can you confirm that this state of affairs does not apply to the concept of "peer-reviewed "in assessing the IPCC reports?

3. "Global warming".

The models in the IPCC reports are assume a continuous global warming. How does this model, account for the already more than 10 years of continuous cooling of the earth? The temperature has not increased anymore in the last 10 years. Nature does not seem to track any of the models! How reliable are the models then?

Those are my questions. I look forward to your response.

ANSWER: Thanks for your comment submitted within the framework of our research on errors in the report of IPCC Working Group II.

Your comment focuses on issues outside the limits of our investigation. However, I want to briefly respond to your letter.

Water vapor is the main greenhouse gas, because water is present in abundance on Earth, and thus relatively high levels in the atmosphere. Approximately two thirds of the greenhouse effect is attributable to water vapor. The important role of water vapor has been completely dealt with by the IPCC. Take a look at this webpage on Climate Portal, which Bart Strengers of PBL in a discussion with Hans Labohm including addresses the role of water vapor: http://www.klimaatportaal.nl/pro1/general/start.asp?i=0&j=0&k=0&p=0&Itemid=367 (in Dutch, use Google Translate to get an idea)

As to the effect on the CO2 concentration of the 3% anthropogenic emissions of CO2, I refer you to to this Web Portal on Climate: http://www.klimaatportaal.nl/pro1/general/start.asp?i=0&j=0&k%20=%200&p%20=0&Itemid=565

You also ask about the review process of the IPCC. You can see what happened to the comments on the IPCC website. See http://hcl.harvard.edu/collections/ipcc/index.html where comments on each chapter and each stage of the process is documented showing all the comments. Click on a section and see in the rightmost column, the responses of the IPCC authors.

Finally, a response to your comment about global warming over the past 10 years. Climate models show not only an increase in temperature. Climate models take into account natural variations in temperature over a period of 10-15 years, including temporary cooling, even when CO2 concentrations are continually rising. See for example the scientist-versus-skeptic blog on the website of the NIS: http://weblogs.nos.nl/klimaat/2009/12/17/wedden-dat-het-opwarmt/

The causes of limited warming in the last 10 years is under discussion in science. See:
- Solomon et al., Science 5 March 2010, Vol. - Solomon et al, Science 5 March 2010, Vol. 327. 327. no. 5970, pp. No. 5970, pp. 1219 - 1223: http://www.sciencemag.org/cgi/content/short/327/5970/1219 1219 - 1223: http://www.sciencemag.org/cgi/content/short/327/5970/1219
- News in Climate Science and Exploring Boundaries (december 2009). - News in Climate Science and Exploring Boundaries (December 2009). On our website see: http://www.pbl.nl/en/publications/2009/News-in-climate-science-and-exploring-boundaries.html .

When our investigation is completed, we will inform you of the results.