cc: Jerry Meehl , Jonathan Overpeck , Phil Jones date: Thu, 25 Jan 2007 09:51:05 -0700 from: Caspar Ammann subject: [Fwd: Re: [Fwd: Recommended reading?]] to: Tom Wigley , Kevin Trenberth Tom and Kevin, below the summary I just sent to a few realclimate folks for further comment. I will keep you posted on any additional information that is coming. Caspar Well, if I recall right the most recent 'venting' on climateaudit did go towards the hurricanes and sea level. Currently their site is not responding, and it might just be strategic... I would assume that they are going to launch a multi-pronged approach trying to undermine a string of arguments that are currently either in the chain to link to GHG forcing and/or that have one of the biggest impacts in the popular perception. Its going to be in their usual fashion: Stir up a lot of dust and move to the next thing before anybody can answer. In the end there is little left... Trying to interpret a priority list from my personal feeling of this guy. I do this based on a google-cash because his site is down or something. So here is my hunch/speculation. I'll see if I can get the document somewhere but I'm not very optimistic about this. By the way, I'm also going to forward this to Susan an few others that might have heard the rumor. Before I do send it to Susan, you might chip in on this list for "internal and IPCC use": - keeps bugging away about the HadCRUT3 data, looking at some individual grid cells. - stationarity in the climate system (see below; but my hunch is that they go for much larger real world variability than in most models, and thus there is a chance that its all noise; so their argument. Of course the space-time-geophysical process framework is much stronger, but at least this is a direction they might go; key is that models are only one way to do detection-attribution). - declining temperatures in Antarctica: inconsistent with polar amplification ... not sure if he knows that central Antarctica has no sea ice feedback, but more importantly what circulation changes can do (difference vortex inside and outside) - "Statistics of Rekordbreaking Temperatures": human landuse/heat island effect; also check this paper that McIntyre has been looking at (single point: Philadelphia and record breaking temperatures): http://arxiv.org/PS_cache/physics/pdf/0509/0509088.pdf - hurricanes are a poisson process not driven by a systematic underlying forcing increase. - Arctic ice shelves: break off individual parts not unusual. Arguments might come that initial breakup started 1930s not now and "everybody" knows that it has been warm then when CO2 was low... etc. - Satellite record (Mears-Wentz and also Christy): Not uniform warming at all... he points out that S-Hem is flat. - solar: well one could only hope that he follows the so-idiotic-that-its-already-funny versions that Haemeranta is sending around. Sun is as active as never before, and then the predictions are for cooling... I think MM will try to simply say that solar contributions have been not well included and are actually much more important. By the way: Ammann et al. has now been accepted by PNAS, should have a say in the solar influence... - climate reconstructions 1 (the obvious and usual): key issues are bring proxies up to date, contamination of all reconstruction with bad data that is shared and thus all are wrong, secrecy in proxy data - climate reconstructions 2: Maybe the "bomb" is their claim of non-stationarity. Maybe they want to show that calibration on present day is tainted with problems, jumping on the bandwagon of VS that degrees of freedom are limiting stats. My answer of course is think physically and use time history... (some paper by Sonechkin, which really doesn't understand how field reconstructions work, but the stationarity issue is more difficult to blow off the table with arguments... maybe we should be prepared for that one). - climate reconstructions 3: Tree line and glaciers as indicators: It was "warmer" before so why bother now. My answer generally is that we have a GW signal of 30 years. If in medieval times there would have been current temperatures for the durations as it had in these times (different actual timing in different locations) then the so called signal of Medieval Warm Period would be much stronger. Currently almost nothing is in equilibrium. Glaciers are collapsing (mass!) not simply melting and the trees take many decades to change the tree line. - sneaking in papers into AR4 that were past deadline -- Caspar M. Ammann National Center for Atmospheric Research Climate and Global Dynamics Division - Paleoclimatology 1850 Table Mesa Drive Boulder, CO 80307-3000 email: ammann@ucar.edu tel: 303-497-1705 fax: 303-497-1348 -- Caspar M. Ammann National Center for Atmospheric Research Climate and Global Dynamics Division - Paleoclimatology 1850 Table Mesa Drive Boulder, CO 80307-3000 email: ammann@ucar.edu tel: 303-497-1705 fax: 303-497-1348