cc: "Keith Briffa" , Jonathan Overpeck date: Thu, 21 Jul 2005 16:16:20 +0100 from: Tim Osborn subject: Re: NH Borehole Timeseries to: Jason Smerdon ,Henry Pollack Dear Henry and Jason, thanks for the NH borehole temperatures which you sent some weeks ago. The decision has now been made by the lead authors to also include a figure showing some local/regional Southern Hemisphere temperature reconstructions in the IPCC paleo chapter. It wouldn't be complete without some borehole inversions too! I have data from the Huang et al. (2000) analysis which I could add to the figure, but thought I'd first check whether you have either an SH series, or series for southern Africa and Australia, that you would prefer to be used (perhaps with gridding and weighting before averaging, and/or with the zero point adjusted in the same way that you did for the NH)? Please let me have your views on this, as well as suitable time series if you have them. Cheers Tim At 18:53 13/06/2005, Henry Pollack wrote: >Hi Tim, > >Attached is the Northern Hemisphere timeseries for the boreholes, an area- >weighted average from a five-degree grid. It includes a mean reconstruction >and two uncertainty timeseries representing +/- 1 standard error. We have >referenced the series to the zero crossing of the NH SAT (total). This is >after the Moberg et al. paper in which the crossing year was determined to be >1958.5. That reference for the SAT data is: > >Jones, P.D. and A. Moberg, Hemispheric and large-scale surface air >temperature variations: An extensive revision and an update to 2001. J. >Clim. 16, 206223 (2003). > >The reference for the borehole reconstruction is Pollack & Smerdon (2004). > >If you and Keith are using another subset (land only?) or version of the SAT >data please send us the year of the zero-crossing of the 20th-century SAT >trend >in the dataset you are using. We can reference from there >accordingly. Let me >or Jason know if you have any questions. I am leaving for Australia next week >and Jason is also traveling a little, so please let us know ASAP if you need >something different. > >Cheers, >Henry > Dr Timothy J Osborn Climatic Research Unit School of Environmental Sciences, University of East Anglia Norwich NR4 7TJ, UK e-mail: t.osborn@uea.ac.uk phone: +44 1603 592089 fax: +44 1603 507784 web: http://www.cru.uea.ac.uk/~timo/ sunclock: http://www.cru.uea.ac.uk/~timo/sunclock.htm