cc: schlesin@atmos.uiuc.edu date: Wed, 28 Feb 2007 13:15:40 -0600 from: Michael Schlesinger subject: Re: Fred Singer's Hypothesis to: Phil Jones Phil: Attached are 2 papers by Gerard Bond that describe a 1470-year oscillation in the Holocene. What are your thoughts on these papers? Michael >Michael, > Not that I've ever seen. You have to believe the various > series for the last 1000 years, and then they aren't long enough. > I've just been looking at isotope series from some Greenland cores > for the last 10K years and there was no evidence to my eyes. > Not done any spectral analysis though ! > > Cheers > Phil > > >At 16:11 26/02/2007, you wrote: >>Phil: >> >>Is there any evidence for a 1500-year cycle in the Holocene? >> >>Michael >> >>>Mike, >>> The YD is a very distinct event. It is now almost exactly dated - >>> see this paper. >>> >>> •Rasmussen et al. (2006) A new Greenland ice >>>chronology for the last glacial termination, >>>JGR 111, D06102, doi:10.1029/JD2005006079. >>> >>> •Based on cross-dated Greenland ice cores, >>>the onset now dated to 12896 b2K ± 140 years >>>•End dated to 11703 b2K ± 100 years >>>•Duration of 1193 ± 40 years >>> >>> b2k is AD 2000 >>> >>> The 8.2K event is a little less clear, but still has a duration that can be >>> estimated. >>> >>> These aren't the DO events, but they are similar. They are both very >>> abrupt and occurring in the space of a few years. The resolution >>> in the ice cores back before 21K is less good, that you can't see the >>> events so clearly, but the belief is that >>>they are abrupt events not cycles. >>> >>> Also, if he says the CRU data cool after 1998, tell him to work out >>> the trend for the period 1998 to 2005 or 2006. The trend is still upwards >>> despite starting with the warmest year! >>> >>> See you in South Korea, apparently. >>> >>> Cheers >>> Phil >>> >>> >>> >>> >>>At 14:04 26/02/2007, you wrote: >>>>Phil: >>>> >>>>I will be on a radio program this (Monday) >>>>evening debating global warming with Fred >>>>Singer. >>>> >>>>According to Fred's book, Unstoppable Global >>>>Warming, Every 1,500 Years, the warming we >>>>have observed is due to the 1500-year DO >>>>'oscillation', not the greenhouse effect. >>>> >>>>But, as far as I know: (1) the DO's are an >>>>abrupt event, not an oscillation; and (2) the >>>>DO events ceased at the end of the last ice >>>>age, about 23K years ago. >>>> >>>>Accordingly, what are your thoughts on Fred's hypothesis? >>>> >>>>Regards, >>>> >>>>Michael >>> >>>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 p.jones@uea.ac.uk >>>NR4 7TJ >>>UK >>>---------------------------------------------------------------------------- > >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 p.jones@uea.ac.uk >NR4 7TJ >UK >---------------------------------------------------------------------------- > Attachment Converted: "c:\eudora\attach\Bond-etal-Science97.pdf" Attachment Converted: "c:\eudora\attach\Bond_etal-Science01.pdf"