From: Simon Tett To: Peter Stott , Gareth Jones , Myles Allen , Phil Jones , Keith Briffa Subject: Tuesday Meeting Date: Wed, 17 Feb 1999 23:01:45 +0000 Dear all, thank you for the meeting on tuesday. I think it went well. Here as promised and slightly late is a summary of what we discussed. Myles can you forward the message to Michael. Can you let me know if you are all happy with this and once I have made any corrections you want I'd like to send it to John, Geoff and Tim Barnett -- anyone else you think should get it? Proxy Climate forcing. Solar -- Beer has a Be based proxy reconstruction of Solar ACTIVITY which can be converted to irradiance changes. [Is it different from LBB or H&S ?] Has the LBB dataset been updated? Has Svensmark got a better handle on his proposed physical mechanisms to amplify solar irradiance changes? [Someone to check at RMS meeting which I won't be able to attend] Want forcing back to 1600?? though HC would find it hard to justify doing runs that early -- me to see if John/Geoff think useful or not. Me to check with William the source of the rumour about problems with the H&S dataset. Volcanoes. Volcanoes are an important climate forcings [Issue for IPCC??] Do volcanic erruptions cluster? Myles to "persuade" a student to look at Phil/Keith's dataset and see if there is evidence for this? Are there other indices of volcanic activity? Is climate response to volcanoes sensitive to mean state?? i.e. in cooler climate get bigger response. [Gareth could see from our model if Krakota response significantly different from Pinatubo] Proxy Climate data + comparision with obs and models. Keith/Phil have 400 sites of high quality tree ring density data which there are willing to let HC (Mat) use to do a crude model/data comparision. Mat and Tim to liase on what they are doing. Note that funny things are happening in the density data post 1950. Also available may be some borehole data [Phil to talk to Pollock/Wang about possibility] which could use to compare with model -- should consider using lower soil temperature rather than 1. m temp. There are a few sites with data from 0A to 2000 as well as many sites with data for 1700 to 2000 -- should consider both. There may be some other tree ring data which tells us something about SW USA precip and thus ENSO. Tim wants to compare patterns of temperature var from the proxy data and compare that with the models i.e compare "observed" and modelled covariance structure rather than just the variability. Also Tim wants to try and unpick Mann's stuff.... HC to provide solar forced run from 1700 -- Me to check if it goes from 1700! Our approach will be to compare model data "directly" with Proxy data rather than do Interpolation a la GISST or Mann et al. EU proposal Not clear if in this years framework 5 call there will be room for Detection/Attribution proposals (which is how we'd like to frame a model/proxy comparision). Other issue is that QUARCC 2 and model/proxy comparision could involve similar institutions which could cause problems. Phil to check if room this year for proposal. Keith pointed out that we can't just recycle the NERC thematic proposal (PRESIENT). There is good news on that fron which suggests the proposal will go through with an 8 million pound budget!!! Ad Hoc detn group. Not much said on that (or at least I didn't note it) Phil -- you have some advice for me on that? CLIVAR/PAGES In the next 1-2 years there may be new reasonable quality ice core and sedimentation data available. Data availablity from the proxy and modelling groups is an issue (another reason for an EU proposal!). Phil pointed out that there is a lot of instrumental data (in "funny" units) which could be digitised in Europe. Keith is planning on writting a "call to arms" paleo data paper. I think I need to come up with a list of actions.... Anyone want to volunteer..... Simon