date: Fri, 02 Mar 2001 16:59:02 +0000 from: Keith Briffa subject: Fwd: RE: response to Wally to: rbradley@geo.umass.edu,t.osborn@uea.ac.uk While writing the stuff below, Mike and Tom's messages came in. Now I'm confused and going home in the thick snow! Earlier- See Julia's message below . Well , what about saying something about the way Wally's letter highlights the need for well-dated proxies with realistic interpretations of their meaning. Otherwise we fall into the trap of smearing the picture of past variations and loose ourselves in the mist of poorly resolved definitions of warmth and cold (that then support wooly arguments about regional/global forcing). Could also point out that even if MWP real , what is needed is quantitative indication of its precise nature - how warm and where at what time, and WHY . Without knowing whether the underlying natural forcing(s) is(are) amplifying or damping the potential present day warming , it is not enough to state (even if its true) that the MWP was or was not global or warmer than today. There is room for speculation that the N.Atlantic may have warmed and cooled during the Holocene - but before you can imply this is evidence of a global "cycle" , you need to establish that the dating and magnitude of climate oscillations that might be interpreted from the Bond data agree with very widespread evidence better than chance. The data Wally has chosen to use in his piece don't do that and don't tell us about the relative magnitude of the warmings (in the N.Atlantic or the globe). Hence , invoking poorly resolved data (in terms of time and magnitude of warmth) don't really get us far. Hence Wally is right that we need more data. Also perhaps say that these proxies do have problems , but they are being addressed and can be more so when we have more of them and especially recent data to judge the potential for their underestimation of modern and past warmth. Etc.??? >From: "Julia Uppenbrink" >To: "Keith Briffa" >Subject: RE: response to Wally >Date: Fri, 2 Mar 2001 16:24:24 -0000 >X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) >Importance: Normal > >Dear Keith: > >It was just a suggestion that one letter would be better - if the viewpoints >cannot be reconciled two or more letters are fine. I cannot promise that any >of them will get published, however! We will first get a response from Wally >and then review the exchange (inhouse and possible with outside input). Then >the letters editor decides whether to proceed to publication. All of this >said, I am personally interested to hear your concerns, and look forward to >receiving your letter(s). > >Best regards > > Julia > >-----Original Message----- >From: Keith Briffa [mailto:k.briffa@uea.ac.uk] >Sent: 02 March 2001 16:13 >To: Juppenbrink@science-int.co.uk >Cc: rbradley@geo.umass.edu; t.osborn@uea.ac.uk >Subject: response to Wally > > >Julia >there has been some discussion among some of my colleagues and I about a >response to Wally Broecker's perspectives piece in the recent issue of >Science. Several of us were unhappy about it for various reasons as you >know and several versions of a draft response have done the email rounds . >Eventually it fell to Mike Mann and Tom Crowley to lead this effort - but >it has become clear that several of us see different areas that we consider >need addressing . The outcome is that , as of now, several of us have >decided not to sign the draft as it eventually emerged, leaving ,I think, >Mike Mann, Tom Crowley and Phil Jones as likely authors. However , I think >it would be interesting to allow another viewpoint or two in the form of >an additional one or two letters. What do you think? I got the impression >that you would prefer only one response. I would not like to go through >another round of writing only to be informed that it was not your >policy to accept multiple responses to a perspectives piece. >Best wishes >Keith > >-- >Dr. Keith Briffa, Climatic Research Unit, University of East Anglia, >Norwich, NR4 7TJ, United Kingdom >Phone: +44-1603-593909 Fax: +44-1603-507784 -- Dr. Keith Briffa, Climatic Research Unit, University of East Anglia, Norwich, NR4 7TJ, United Kingdom Phone: +44-1603-593909 Fax: +44-1603-507784 -- Dr. Keith Briffa, Climatic Research Unit, University of East Anglia, Norwich, NR4 7TJ, United Kingdom Phone: +44-1603-593909 Fax: +44-1603-507784