date: Mon Jul 25 11:25:10 2005 from: Phil Jones subject: Changes to 3.4 to accommodate Sherwood et al OK to: Kevin Trenberth Kevin, Changes to section 3.4.1.1/2/5 are all OK. Phil At 19:17 22/07/2005, you wrote: Phil Rumour has it that all three will be together. I have made changes in 3.4.1 and they turn out to be non trivial: 3.4.1.1 I moved the Haimberger para to second last and added stuff: A new development in approaches to improve radiosonde data has been to use the bias-adjustments estimated during data assimilation into model-based reanalyses (Haimberger, 2005). Despite the risk of contamination by other biased data in the assimilation, or by model biases, the adjustments are found to agree with those estimated by existing methods. In another major new development, Sherwood et al. (2005) has found substantial changes in the diurnal cycle as measured by sondes that are almost certainly a consequence of improved sensors, which have have become much smaller over time, reducing the radiation effects. Hence relative to nighttime values, they find a daytime warming of sonde temperatures prior to 1971 that is likely spurious and then a daytime cooling, especially from 1979 to 1997 during the satellite era, that is also spurious. Thus there is likely a spurious downward trend in sonde temperature records throughout the atmosphere after 1979 of order 0.1°C globally: the assessed spurious cooling is greatest in the tropics of 0.16 K decade^1 for the 850 to 300 hPa layer, and least in the NH extratropics of 0.04 K decade^-1. End of 3.4.1.2 now reads: While comparisons of radiosonde station data with collocated satellite data (Christy and Norris, 2004) suggest that the median trends of radiosonde temperatures in the troposphere are very close to UAH trends and a little less than RSS trends, comparisons of trends at individual radiosonde sites vary and root mean square differences of UAH satellite data with radiosondes are substantial (Hurrell et al., 2000). Moreover, radiosonde data contain diurnal cycle influences (Sherwood et al., 2005) that lead to spurious cooling throughout the atmosphere from 1979 to 1997, and residual spurious downward jumps (Randel and Wu, 2005), so that they are compromised by multiple problems (Section 3.4.1.1 and Appendix 3.A.5.1). In the stratosphere, radiosonde trends are more negative than both MSU retrievals, especially when compared with RSS, and this too is likely due to changes in sondes (Randel and Wu, 2005). In 3.4.1.5 I added one sentence at end of para: In the tropics, the theoretically expected amplification of temperature perturbations with height is borne out in interannual fluctuations (ENSO) in radiosondes, RSS and with models (Santer et al., 2005), and only the radiosonde records are at odds for trends. If the latter were corrected for radiation effects (Sherwood, et al. 2005), then they too show increased warming with altitude. Kevin Phil Jones wrote: Kevin, Whilst in Exeter, I got this from Peter Thorne (who is reviewing it for Science). I suspect we should be referring to it, just as an addition to the Randel and Wu paper. It would seem that Bill is aware of this. Maybe you've already seen this. Peter went on about not passing this on to anyone else and also what Ch 3 should be concluding about the whole LT issue and what CCSP says. I felt what he was saying was far too strong, so won't go into it. He is my ex-student - I hope the situation won't go as far as you have with one of your ex-students! CCSP should be available from Aug 15 publicly until Sept 30. Then they have a meting in mid-Oct to finalize everything and all will be printed by Oct 31 ! They've been told they can't change anything once they leave O'Hare at the end of the meeting. The attached paper is tentatively accepted, as is Santer et al. Peter didn't know about Mears and Wentz. The plan is for Science to put all three out together asap, but this is also confidential. Most of the chapters for CCSP are coming along well - except for the Pielke one, now there's a surprise. He's not happy with the Peterson paper on E. Colorado. I'll email again later today with some more on the FOD. Downloaded the latest draft and figs. First I need to get comments back on Brohan et al. so that can be submitted. 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 [1]p.jones@uea.ac.uk NR4 7TJ UK ---------------------------------------------------------------------------- -- **************** Kevin E. Trenberth e-mail: [2]trenbert@ucar.edu Climate Analysis Section, NCAR [3]www.cgd.ucar.edu/cas/ P. O. Box 3000, (303) 497 1318 Boulder, CO 80307 (303) 497 1333 (fax) Street address: 1850 Table Mesa Drive, Boulder, CO 80303 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 ----------------------------------------------------------------------------