cc: Peter Stott , David Pierce , Knutti Reto , "Zwiers,Francis [Ontario]" , Tim Barnett , Hans von Storch , ClaudiaTebaldi , Phil Jones , David Karoly , Toru Nozawa , Ben Santer , Daithi Stone , Richard Smith , Nathan Gillett , Michael Wehner , Doug Nychka , Xuebin Zhang , "Bamzai, Anjuli" , Chris Miller , Tom Knutson date: Mon, 01 Sep 2008 16:40:40 +0100 from: Gabi Hegerl subject: RE: priority list for MIP to: Myles Allen HI everybody, sounds great! I had some amplified solar forcing runs with HadCM3 in a proposal for the last 500 yrs, and the reviewers HATED that - so not sure it will work for convincing sceptical people... I agree that some more simulations would be highly useful, particularly also if going beyond 2000...so should be listed but along with land use maybe? Gabi Quoting Myles Allen : > Dear Peter, > > Thanks for this. This should definitely be done for AR5: recent papers > such as Lockwood and Frolich suggest that data since 2000 should be very > informative with regard to the likelihood of a strong solar > amplification, so it's a bit embarrassing that most direct simulations > of solar influence on climate only run up to 2000 (if they even make it > that far). > > Myles > > -----Original Message----- > From: Peter Stott [mailto:peter.stott@metoffice.gov.uk] > Sent: 01 September 2008 16:27 > To: Myles Allen > Cc: Gabi Hegerl; David Pierce; Knutti Reto; Zwiers,Francis [Ontario]; > Tim Barnett; Hans von Storch; ClaudiaTebaldi; Phil Jones; David Karoly; > Toru Nozawa; Ben Santer; Daithi Stone; Richard Smith; Nathan Gillett; > Michael Wehner; Doug Nychka; Xuebin Zhang; Bamzai, Anjuli; Chris Miller; > Tom Knutson > Subject: RE: priority list for MIP > > Re the solar forcing we were discussing this very issue over lunch at > the Met Office last week. To my knowledge, our 2003 detection study "Do > models underestimate the solar contribution to recent climate change", > J. Climate, 2003, has not been updated since then, even though, because > of degeneracy between the GHG and solar response, the conclusions of > that paper were heavily caveated (our "perfect model" analyses indicated > we might have been attributing too much warming to solar forcing). > > What we need to update this study are model simulations with large solar > forcing and ideally model studies that include a representation of uv on > stratospheric ozone and we could I suppose have a go at trying to > simulate the effect of cosmic rays in a model in some highly simplified > way. > It seems to me that this is something for a few interested groups to do > rather than requesting everyone to do, since we could gain a lot of > value from simulations with a single model or just a few models. > > Peter > > On Mon, 2008-09-01 at 15:27 +0100, Myles Allen wrote: >> Dear Gabi, >> >> That sequence looks good to me. It might be worth emphasizing to the >> modelers that we want as many takes as possible on the question of how >> much warming can be attributed to past anthropogenic greenhouse > forcing, >> so the GHG-only runs are interesting in their own right, not just for >> D&A. >> >> What solar forcing is being recommended (apologies if the answer to > this >> is in an earlier e-mail)? The one question it would be hard to answer >> with that lot is Svensmark's: how much warming can be attributed to a >> (possibly amplified) solar forcing? Are we anticipating that this >> question will have become completely uninteresting by 2013? >> >> Myles >> >> -----Original Message----- >> From: Gabi Hegerl [mailto:Gabi.Hegerl@ed.ac.uk] >> Sent: 01 September 2008 14:55 >> To: Gabi Hegerl; David Pierce >> Cc: Myles Allen; Knutti Reto; Stott, Peter; Zwiers,Francis [Ontario]; >> Tim Barnett; Hans von Storch; ClaudiaTebaldi; Phil Jones; David > Karoly; >> Toru Nozawa; Ben Santer; Daithi Stone; Richard Smith; Nathan Gillett; >> Michael Wehner; Doug Nychka; Xuebin Zhang; Bamzai, Anjuli; Chris > Miller; >> Tom Knutson >> Subject: priority list for MIP >> >> Hi IDAG people, I forwarded the comments to Karl. >> >> One thing that Jerry and Karl would find helpful is a priority list >> from us about runs important for detection and attribution. >> if I write this (in a hurry so dont take terribly serious) I would get >> the following priorities: >> 0. control simulation longer than 150 yrs >> 1. 1 All forcing 20th century simulation (1860-2015, ideally >> even earlier start) >> 2. two more 20th century simulations particularly if control >> shorter than 500 yrs >> 3. 1 Natural only forcing 20th century simulation >> 4. 1 Ghg only simulation >> 5. 2 more natural only simulations >> 6. 2 more ghg only simulations >> from here on its a bit of a tossup >> 7. 1-3 land use change simulation >> 8. 1-1 volcano simulation >> >> what do you think - how would you splice? I tend to favor the >> simualtion that is closest >> to whats actually happening if having an opion of say ALLminus a >> forcing or a forcing >> alone. >> >> ALso, as soon as Karl has the suggested list of variables to be saved > >> I will circulate for feedback! >> >> Gabi >> >> Quoting Gabi Hegerl : >> >> >> >> -- >> Gabriele Hegerl >> School of GeoSciences >> University of Edinburgh >> http://www.geos.ed.ac.uk/people/person.html?indv=1613 >> > > -- Gabriele Hegerl School of GeoSciences University of Edinburgh http://www.geos.ed.ac.uk/people/person.html?indv=1613 -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.