From: "Michael E. Mann" To: Kevin Trenberth Subject: Re: recent WSJ article Date: Fri, 14 Sep 2007 15:26:13 -0400 Reply-to: mann@psu.edu Cc: Phil Jones , Richard Somerville Kevin, can you send me the link once its up? thanks, Mike Kevin Trenberth wrote: Mike You should have seen the first version. I drafted that yesterday and then today toned it down. I did add a couple of points, including the link you suggested. Will try to send off later today but just to nature.com Thanks Kevin Michael E. Mann wrote: guys, I've got a few minutes before I have to head out again. Kevin--thanks for helping return the Nature blog to respectability after a dubious start...I'd like to direct RealClimate readers to your piece as soon as it is up, so please let me know when that happens... Looks like Phil has hit several of the key points, but here are a few more: 1. The 'discrediting' that Akasofu cites has been discredited. IPCC Chapter 6 rejected the McIntyre and McKitrick's claims in no uncertain terms, referencing the Wahl and Ammann work (reprints attached) who show that (a) the reconstruction is readily reproducible and (b) McIntyre and McKitrick only failed to reproduce the reconstruction because of multiple errors on their part. This is true in addition to the more general point that Kevin has made (that multiple independent studies confirm and in fact now extend the previous conclusions, rather than contradict them). 2. To the extent that the "LIA" and "MWP" can be meaningfully defined, there has been much work (published in Nature, Science, etc.) showing that the main variations (both in terms of hemispheric mean changes and spatial patterns) can indeed be explained in terms of the response of the climate system to natural radiative forcing changes (solar and volcanism). Only someone completely unfamiliar with the advances of the past ten years in climate science would claim that there are no explanations for these. 3. Continuing in this theme, to claim that the modern warming is some sort of 'rebound' reflects a thorough apparent lack of understanding of how the climate system works. The climate doesn't rebound. It responds (with some lag) to changes in radiative forcing. The main patterns of variation of past centuries have been explained in terms of such responses to natural radiative forcing changes. As shown in countless studies, the late 20th century warming can only be explained in terms of the response to anthropogenic changes in radiative forcing. Kevin has more or less already made this point, in different words, in the current draft. 4. The bogus talking point that co2 lagging the warming in the ice cores has been debunked countless times before, and its an embarassment that it continues to be raised by one who ostensibly considers himself a scientist. This is total nonsense, and a nice refutation has been provided by Eric Steig on RealClimate here: [1]http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/ Perhaps worth just linking to that explanation? Kevin, perhaps you're too gentle in attributing this simply to some 'confusion' about the facts. Either Mr. Akasofu has literally no familiarity whatsoever with the advances in climate science of the past two decades, or he has intentionally sought to deceive. In either case, his piece is embarassment. Finally, let me withdraw my initial suggestion. For strategic reasons, it might make sense to submit this as letter to editor to WSJ (easy and quick to do online), and then publish it on the Nature blog in short order. I sea that as win-win because you can either call the WSJ for refusing to run your letter (which is very likely what will happen), or use the Nature blog piece to draw attention to your letter, should WSJ actually choose to publish your letter... please don't hesitate to let me know if I can be of any further help here. Will be back online a bit later today, mike Phil Jones wrote: Kevin, A few quick thoughts. Article is awful as we all know. It is important to learn about past climate change, especially over the past 1000 years, but it is even important to use new and improved evidence from proxy sources (i.e. not to cling to outdated concepts of the past such as the MWP and LIA). How can we ever hope to progress if we have conform to incorrect concepts? On the early mid-20th century warming - look at the figures in Ch 9. The decrease from 1940-75 didn't happen if you look at global records. MBH was published in 1998 and wasn't just a tree-ring study. The Thames doesn't and never did freeze solid. It did so 25 times between 1400 and 1820. Only about 5-6 of these were frost fairs. Most of these have CET data, so what is the use of the freeze dates! He plucks various figures out of the air! I think the reductions in Arctic sea ice this summer/September are alarming. They are 20% below the 2005 record. He comes from Alaska. Has he not seen the effects on the coast there? Cheers Phil Prof. Phil Jones Climatic Research Unit Telephone +44 (0) 1603 592090 School of Environmental Sciences Fax +44 (0) 1603 507784 University of East Anglia Norwich Email [2]p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- -- Michael E. Mann Associate Professor Director, Earth System Science Center (ESSC) Department of Meteorology Phone: (814) 863-4075 503 Walker Building FAX: (814) 865-3663 The Pennsylvania State University email: [3]mann@psu.edu University Park, PA 16802-5013 [4]http://www.met.psu.edu/dept/faculty/mann.htm -- **************** Kevin E. Trenberth e-mail: [5]trenbert@ucar.edu Climate Analysis Section, NCAR [6]www.cgd.ucar.edu/cas/ P. O. Box 3000, (303) 497 1318 Boulder, CO 80307 (303) 497 1333 (fax) Street address: 1850 Table Mesa Drive, Boulder, CO 80305 -- Michael E. Mann Associate Professor Director, Earth System Science Center (ESSC) Department of Meteorology Phone: (814) 863-4075 503 Walker Building FAX: (814) 865-3663 The Pennsylvania State University email: [7]mann@psu.edu University Park, PA 16802-5013 [8]http://www.met.psu.edu/dept/faculty/mann.htm References 1. http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/ 2. mailto:p.jones@uea.ac.uk 3. mailto:mann@psu.edu 4. http://www.met.psu.edu/dept/faculty/mann.htm 5. mailto:trenbert@ucar.edu 6. http://www.cgd.ucar.edu/cas/ 7. mailto:mann@psu.edu 8. http://www.met.psu.edu/dept/faculty/mann.htm