cc: eystein.jansen@geo.uib.no, jto@u.arizona.edu, k.briffa@uea.ac.uk, Edward Cook , "Ricardo Villalba" , Jason E Smerdon , Henry Pollack date: Mon, 1 Aug 2005 11:58:49 -0600 from: Jonathan Overpeck subject: Re: SH figure for IPCC AR4 to: Tim Osborn Hi Tim and SH friends - PLEASE try to get feedback to Tim asap - we're almost out of time. The Fig looks nice, thanks! Borehole issue: Are the Australasia boreholes that, or are they just Australia? I think they are the latter, unless you have more updated data from Henry et al. If only Oz, best change in the fig too. Borehole issue: using 95 confidence interval - seems ok to me - lets see what the rest of the gang says. Also, is this compatible with the estimated confidence interval in your other maintext figs - I know this latter one is somewhat unconventional, but it is 1.5 sd, no? Oxygen isotopes - complicated by non-temp issues, therefore we decided not to use in this section/figure. You got it right. Nitpicky - Replace "K" with "°C" on the y axis label. Thanks again, Peck >Dear all, > >attached is my attempt to produce a SH figure >for the draft chapter - in .ps, .pdf and .gif >forms. I tried to make it as compact as >possible, while still keeping the series >separated by a bit of white space between them. > >Here's a draft of the figure caption. Below it >are some QUESTIONS - please read to the bottom! > >Figure XXXXXX. > >Temperature reconstructions for regions in the >Southern Hemisphere: two summer temperature >series from South American tree-ring data; >annual temperature estimates from borehole >inversions for southern Africa and Australia >(derived using the approach of Pollack and >Smerdon, 2004); summer temperature series from >Tasmania and New Zealand tree-ring data (Cook et >al., 2000; 2002). The black curves show summer >or annual instrumental temperatures for each >region. All tree-ring and instrumental series >have been smoothed with a 30-year filter and >represent anomalies (K) from the 1961-1990 mean >(indicated by the horizontal lines). Thin lines >mark the 95% uncertainty range of the borehole >inversions, estimated from inter-borehole >variability. > >Cook ER, Buckley BM, D'Arrigo RD and Peterson MJ >(2000) Warm-season temperatures since 1600 BC >reconstructed from Tasmanian tree rings and >their relationship to large-scale sea surface >temperature anomalies. Climate Dynamics 16, >79-91. > >Cook ER, Palmer JG and D'Arrigo RD (2002) >Evidence for a 'Medieval Warm Period' in a 1,100 >year tree-ring reconstruction of past austral >summer temperatures in New Zealand. Geophysical >Research Letters 29, 14-1667 (doi: >10.1029/2001GL014580). > >QUESTIONS: > >RICARDO: (i) are the Patagonia series both >SUMMER temperature? (ii) please add appropriate >references for these series (iii) did you use a >30-year filter for the Patagonia, Tasmania and >New Zealand series that you sent? -- if not, >please correct what I wrote in the caption. (iv) >are the Patagonia tree-ring reconstructions and >instrumental temperatures that you sent already >expressed as anomalies from 1961-1990 -- if not, >what is the reference period and can it be >changed to 1961-1990 (it is not easy for me to >change it because I only have the filtered >series)? > >JASON/HENRY: (i) I doubled the +-1 standard >error ranges provided by Jason, to get the +-2 >SE range (~95% range?) shown in this figure -- >is that ok? > >ED: (i) are the references I used correct, or do >you have newer ones? (ii) the data that Ricardo >sent me were absolute temperatures not >anomalies, so to get the anomalies I simply >shifted the series so that it's mean matched the >instrumental temperature mean during the >calibration periods you used in these papers >(1894-1957 for NZ and 1920-1991 for TAS) - is >that the correct thing to do? (iii) for the >instrumental temperatures I simply took the >Jones grid box land temperature for the >appropriate box and used the Jan-Mar mean for NZ >and Nov-Apr mean for TAS - is that ok? > >EVERYONE: >(i) I included the 95% uncertainty range on the >boreholes because Jason sent me the necessary >data, but should it be included or not? >Obviously it's useful information, but the >tree-ring reconstructions don't have similar >ranges (although I guess someone has computed >them at some point?). >(ii) the vertical positioning of the borehole >series was done by Jason/Henry and took into >account that many boreholes were sampled before >1980, and thus before the most recent rapid >warming -- therefore they are positioned to give >a better match with the pre-1980 observations >(in fact the median of all sampling dates is the >last year used -- what is it Jason?). Should >this be mentioned in the text (together, >perhaps, with a caveat regarding the poorer >sampling in the SH compared with the NH) or in >the caption, or not at all? Also, should the >borehole time series be stopped at the median >date, rather than continued through to 2000 in >the figure? > >I'd be grateful for any other comments regarding >the figure, as well as answers to these >questions. Phil Jones took a look and asked why >we hadn't included the Law Dome d18O ice core >series from Tas van Ommen - but perhaps you've >already discussed such things in earlier emails? > >Cheers > >Tim > > > > >Attachment converted: Macintosh HD:ipccar4_sh.gif (GIFf/«IC») (0008D900) >Attachment converted: Macintosh HD:ipccar4_sh.ps ( / ) (0008D901) >Attachment converted: Macintosh HD:ipccar4_sh 1.pdf (PDF /«IC») (0008D902) >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 -- Jonathan T. Overpeck Director, Institute for the Study of Planet Earth Professor, Department of Geosciences Professor, Department of Atmospheric Sciences Mail and Fedex Address: Institute for the Study of Planet Earth 715 N. Park Ave. 2nd Floor University of Arizona Tucson, AZ 85721 direct tel: +1 520 622-9065 fax: +1 520 792-8795 http://www.geo.arizona.edu/ http://www.ispe.arizona.edu/