date: Thu Mar 18 14:12:06 2004 from: Phil Jones subject: Re: minor alteration to: "Tas van Ommen" Tas, Will keep in touch. Will send paper when we get a pdf/reprint. I'll look at the annual data when I have some time. Meetings all next week need preparing for and then the April weeks after Easter as well. Not sure when I'll get to it, but I will sometime. Cheers Phil At 22:07 18/03/2004 +1100, you wrote: G'day Phil, Sounds like you are on firm ground if you used the series I sent last year - 4 year resolution will not harm the decadal scale smoothing even if it makes annual correlation somewhat questionable. You need not be worried if you only used my 2003 data - it is based on the best data we have, which are indeed a multi-core stack over much of the calibration period (the header notes from the file give details). This still leaves a point of question over your relatively high r value, and this may be because of the underlying 4 year smooth in your "annual" data. I would recommend that you look at the annual data I sent earlier today and confirm what is going on. As a point of interest, my calibration exercise is revealing that the Law Dome d18O is capturing comparable variance in the mid-latitude SLP field in the eastern Indian Ocean to the local temperature signal near Law Dome. Not surprising when one appreciates the role of cyclonic transport. Do keep in touch - I am happy to help however I can to ensure the best fidelity in our contribution to the paleo-reconstruction. Cheers, Tas -----Original Message----- From: "Phil Jones" Sent: 18/03/04 20:13:27 To: "Tas van Ommen" Subject: Re: minor alteration > Tas, Attached is the series I've used. It does look quite smooth, so it seems to be the 4-yr smoothed one you mention. So it seems the annual correlation I talk about for 1957-80 is based on this against the HadCRUT2v series. Both then get smoothed with the 10-yr Gaussian filter I talked about yesterday. The fact that the Law Dome series I have is already smoothed won't make too much difference to this. I have the old series also, but never compared the two. I say I have it, but it is in an old directory somewhere. Just found it and it has years 1304-1987. Didn't use it though as it was elsewhere and I gave it a different name then. So, I think we're OK. If I understand correctly the del18O data for 1957-99 is based on 3 series and maybe more for this time. What I've been using is just one of these, which goes back 2K years - ends in 1995, and is smoothed. The reason HadCRUT2v isn't exactly like Jo Jacka's series is the variance correction that gets done. This uses the residuals from a 30-year filter for each month separately, reducing the anomaly (from the filter) from a single obs in the box to the infinitely sampled one. Values further from the filter get reduced more than one closer. Upshot will be that the annual series will differ a little, but as the 30-year filtered series get added back, the smoothed series will get closer and closer to the original as you smooth more. All in a paper in J. Climate in 1997. Still doesn't explain why my r-values are as high as they are. Smoothing must be the answer and the period 1957-80. I wasn't worried as I knew I'd used the latest one from last May. Should I be worried? 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 p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- [Message truncated. Tap Edit->Mark for Download to get remaining portion.] 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 ----------------------------------------------------------------------------