From: Tom Wigley To: Gavin Schmidt Subject: Re: BBC U-turn on climate Date: Wed, 14 Oct 2009 16:43:54 -0600 Cc: Michael Mann , Kevin Trenberth , Stephen H Schneider , Myles Allen , peter stott , "Philip D. Jones" , Benjamin Santer , Thomas R Karl , Jim Hansen , Michael Oppenheimer Gavin, I just think that you need to be up front with uncertainties and the possibility of compensating errors. Tom. +++++++++++++++++++++++++ Gavin Schmidt wrote: > Tom, with respect to the difference between the models and the data, the > fundamental issue on short time scales is the magnitude of the internal > variability. Using the full CMIP3 ensemble at least has multiple > individual realisations of that internal variability and so is much more > suited to a comparison with a short period of observations. MAGICC is > great at the longer time scale, but its neglect of unforced variability > does not make it useful for these kinds of comparison. > > The kind of things we are hearing "no model showed a cooling", the "data > is outside the range of the models" need to be addressed directly. > > Gavin > > On Wed, 2009-10-14 at 18:06, Michael Mann wrote: >> Hi Tom, >> >> thanks for the comments. well, ok. but this is the full CMIP3 >> ensemble, so at least the plot is sampling the range of choices >> regarding if and how indirect effects are represented, what the cloud >> radiative feedback & sensitivity is, etc. across the modeling >> community. I'm not saying that these things necessarily cancel out >> (after all, there is an interesting and perhaps somewhat disturbing >> compensation between indirect aerosol forcing and sensitivity across >> the CMIP3 models that defies the assumption of independence), but if >> showing the full spread from CMIP3 is deceptive, its hard to imagine >> what sort of comparison wouldn't be deceptive (your point re MAGICC >> notwithstanding), >> >> perhaps Gavin has some further comments on this (it is his plot after >> all), >> >> mike >> >> On Oct 14, 2009, at 5:57 PM, Tom Wigley wrote: >>> Mike, >>> >>> The Figure you sent is very deceptive. As an example, historical >>> runs with PCM look as though they match observations -- but the >>> match is a fluke. PCM has no indirect aerosol forcing and a low >>> climate sensitivity -- compensating errors. In my (perhaps too >>> harsh) >>> view, there have been a number of dishonest presentations of model >>> results by individual authors and by IPCC. This is why I still use >>> results from MAGICC to compare with observed temperatures. At least >>> here I can assess how sensitive matches are to sensitivity and >>> forcing assumptions/uncertainties. >>> >>> Tom. >>> >>> +++++++++++++++++++ >>> >>> Michael Mann wrote: >>>> thanks Tom, >>>> I've taken the liberty of attaching a figure that Gavin put >>>> together the other day (its an update from a similar figure he >>>> prepared for an earlier RealClimate post. see: >>>> http://www.realclimate.org/index.php/archives/2009/05/moncktons-deliberate-manipulation/). It is indeed worth a thousand words, and drives home Tom's point below. We're planning on doing a post on this shortly, but would be nice to see the Sep. HadCRU numbers first, >>>> mike >>>> On Oct 14, 2009, at 3:01 AM, Tom Wigley wrote: >>>>> Dear all, >>>>> At the risk of overload, here are some notes of mine on the >>>>> recent >>>>> lack of warming. I look at this in two ways. The first is to >>>>> look at >>>>> the difference between the observed and expected anthropogenic >>>>> trend relative to the pdf for unforced variability. The second >>>>> is to remove ENSO, volcanoes and TSI variations from the >>>>> observed data. >>>>> Both methods show that what we are seeing is not unusual. The >>>>> second >>>>> method leaves a significant warming over the past decade. >>>>> These sums complement Kevin's energy work. >>>>> Kevin says ... "The fact is that we can't account for the lack >>>>> of warming at the moment and it is a travesty that we can't". I >>>>> do not >>>>> agree with this. >>>>> Tom. >>>>> +++++++++++++++++++++++ >>>>> Kevin Trenberth wrote: >>>>>> Hi all >>>>>> Well I have my own article on where the heck is global >>>>>> warming? We are asking that here in Boulder where we have >>>>>> broken records the past two days for the coldest days on >>>>>> record. We had 4 inches of snow. The high the last 2 days >>>>>> was below 30F and the normal is 69F, and it smashed the >>>>>> previous records for these days by 10F. The low was about 18F >>>>>> and also a record low, well below the previous record low. >>>>>> This is January weather (see the Rockies baseball playoff game >>>>>> was canceled on saturday and then played last night in below >>>>>> freezing weather). >>>>>> Trenberth, K. E., 2009: An imperative for climate change >>>>>> planning: tracking Earth's global energy. /Current Opinion in >>>>>> Environmental Sustainability/, *1*, 19-27, >>>>>> doi:10.1016/j.cosust.2009.06.001. [PDF] >>>>>> (A PDF of the published version can be obtained from the author.) >>>>>> The fact is that we can't account for the lack of warming at >>>>>> the moment and it is a travesty that we can't. The CERES data >>>>>> published in the August BAMS 09 supplement on 2008 shows there >>>>>> should be even more warming: but the data are surely wrong. >>>>>> Our observing system is inadequate. >>>>>> That said there is a LOT of nonsense about the PDO. People >>>>>> like CPC are tracking PDO on a monthly basis but it is highly >>>>>> correlated with ENSO. Most of what they are seeing is the >>>>>> change in ENSO not real PDO. It surely isn't decadal. The >>>>>> PDO is already reversing with the switch to El Nino. The PDO >>>>>> index became positive in September for first time since Sept >>>>>> 2007. see >>>>>> http://www.cpc.ncep.noaa.gov/products/GODAS/ocean_briefing_gif/global_ocean_monitoring_current.ppt >>>>>> Kevin >>>>>> Michael Mann wrote: >>>>>>> extremely disappointing to see something like this appear on >>>>>>> BBC. its particularly odd, since climate is usually Richard >>>>>>> Black's beat at BBC (and he does a great job). from what I >>>>>>> can tell, this guy was formerly a weather person at the Met >>>>>>> Office. >>>>>>> We may do something about this on RealClimate, but meanwhile >>>>>>> it might be appropriate for the Met Office to have a say >>>>>>> about this, I might ask Richard Black what's up here? >>>>>>> mike >>>>>>> On Oct 12, 2009, at 2:32 AM, Stephen H Schneider wrote: >>>>>>>> Hi all. Any of you want to explain decadal natural >>>>>>>> variability and signal to noise and sampling errors to >>>>>>>> this new "IPCC Lead Author" from the BBC? As we enter an >>>>>>>> El Nino year and as soon, as the sunspots get over their >>>>>>>> temporary--presumed--vacation worth a few tenths of a Watt >>>>>>>> per meter squared reduced forcing, there will likely be >>>>>>>> another dramatic upward spike like 1992-2000. I heard >>>>>>>> someone--Mike Schlesinger maybe??--was willing to bet alot >>>>>>>> of money on it happening in next 5 years?? Meanwhile the >>>>>>>> past 10 years of global mean temperature trend stasis >>>>>>>> still saw what, 9 of the warmest in reconstructed 1000 >>>>>>>> year record and Greenland and the sea ice of the North in >>>>>>>> big retreat?? Some of you observational folks probably do >>>>>>>> need to straighten this out as my student suggests below. >>>>>>>> Such "fun", Cheers, Steve >>>>>>>> Stephen H. Schneider >>>>>>>> Melvin and Joan Lane Professor for Interdisciplinary >>>>>>>> Environmental Studies, >>>>>>>> Professor, Department of Biology and >>>>>>>> Senior Fellow, Woods Institute for the Environment >>>>>>>> Mailing address: >>>>>>>> Yang & Yamazaki Environment & Energy Building - MC 4205 >>>>>>>> 473 Via Ortega >>>>>>>> Ph: 650 725 9978 >>>>>>>> F: 650 725 4387 >>>>>>>> Websites: climatechange.net >>>>>>>> patientfromhell.org >>>>>>>> ----- Forwarded Message ----- >>>>>>>> From: "Narasimha D. Rao" >>>>>>> > >>>>>>>> To: "Stephen H Schneider" >>>>>>> > >>>>>>>> Sent: Sunday, October 11, 2009 10:25:53 AM GMT -08:00 >>>>>>>> US/Canada Pacific >>>>>>>> Subject: BBC U-turn on climate >>>>>>>> Steve, >>>>>>>> You may be aware of this already. Paul Hudson, BBC˙s >>>>>>>> reporter on climate change, on Friday wrote that there˙s >>>>>>>> been no warming since 1998, and that pacific oscillations >>>>>>>> will force cooling for the next 20-30 years. It is not >>>>>>>> outrageously biased in presentation as are other skeptics˙ >>>>>>>> views. >>>>>>>> http://news.bbc.co.uk/2/hi/science/nature/8299079.stm >>>>>>>> http://blogs.telegraph.co.uk/news/damianthompson/100013173/the-bbcs-amazing-u-turn-on-climate-change/ >>>>>>>> BBC has significant influence on public opinion outside >>>>>>>> the US. >>>>>>>> Do you think this merits an op-ed response in the BBC from >>>>>>>> a scientist? >>>>>>>> Narasimha >>>>>>>> ------------------------------- >>>>>>>> PhD Candidate, >>>>>>>> Emmett Interdisciplinary Program in Environment and >>>>>>>> Resources (E-IPER) >>>>>>>> Stanford University >>>>>>>> Tel: 415-812-7560 >>>>>>> -- >>>>>>> Michael E. Mann >>>>>>> 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: mann@psu.edu >>>>>>> >>>>>>> University Park, PA 16802-5013 >>>>>>> website: http://www.meteo.psu.edu/~mann/Mann/index.html >>>>>>> >>>>>>> "Dire Predictions" book site: >>>>>>> http://www.essc.psu.edu/essc_web/news/DirePredictions/index.html >>>>>> -- >>>>>> **************** >>>>>> Kevin E. Trenberth e-mail: trenbert@ucar.edu >>>>>> >>>>>> Climate Analysis Section, >>>>>> www.cgd.ucar.edu/cas/trenbert.html >>>>>> >>>>>> NCAR >>>>>> 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 >>>> 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: mann@psu.edu >>>> >>>> University Park, PA 16802-5013 >>>> website: http://www.meteo.psu.edu/~mann/Mann/index.html >>>> >>>> "Dire Predictions" book site: >>>> http://www.essc.psu.edu/essc_web/news/DirePredictions/index.html >>> >>> >> -- >> Michael E. Mann >> 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: mann@psu.edu >> University Park, PA 16802-5013 >> >> website: http://www.meteo.psu.edu/~mann/Mann/index.html >> "Dire Predictions" book site: >> http://www.essc.psu.edu/essc_web/news/DirePredictions/index.html >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> >>