Testing testing… is the EGU wireless network working? Yes. Good. Unlike the mike of the current speaker :-(

Anyway, following a late (1 a.m.; flight delay, then the Ryanair coach took the backroads to avoid the motorway tolls; then dumped us on the outskirts of vienna) arrival at my hotel, and an early start (6 a.m. UK time; once again I forgot to pre-register; but this year the registration is very fast due to automation, even though I forgot my cosis-number) I get to the end of my parentheses… I mean I get to the conference. Its now a bright sunny morning.

Usually I’d have checked the schedule over breakfast but I’ve only just got the programme; first off, some radiosonde stuff. Sonde/MSU/Sfc has been in the news, and there are two talks about homogenising the sonde record. Gruber et al look at 50 hPa and finds problems which they are trying/succeeding to fix for RAOBCORE (Radiosonde observations corrections for re-analysis) which is sponsored mostly by ECMWF, for the obvious reasons. Coleman (McCarthy and Thorne) from the Hadley Centre look at tropospheric trends. They confirm the Sherwood findings: that day/night diffs do seem to indicate spurious trends. But Sherwood only identified the problem; what needs to be done is to correct the record. Inhomogeneity adjustements by hand are slow and painful; they try automating it. This allows them to do hundreds of different test adjustments and see what spread of trends this produces. They can get a global trend of 0.24 oC; but that I think was the top end; they didn’t produce at this stage what they might consider a “best” trend. www.hadobs.org if you want to poke around.

Hot tip for the afternoon: Ruddiman, at 1:30.

Lunch: EGU/Austria centre catering still can’t really stand the strain of all the people, though the queues aren’t too bad this year.

Ruddiman was good, presents his case well. Mind you the questions were 5 against, 1 neutral. Slight update to the hypothesis: he now admits that the 40 ppmv of CO2 can’t all have come from ag/burning; only about 10 could. So he has to turn to ocean feedbacks to get the rest (this also gets rid of the isotopic signature problem) (my thought: at the moment, ocean feedbacks are contributing to a reduction of CO2 in ressponse to anthro increase, why was it different then?). Still he sticks to the methane bit. Q: the methane upturn is sharp, yet any pop inc would have been smooth. Why? R’s response is the sudden discovery and spread of irrigation in China. Does this convince?

Press conference (thought I’d go, for fun: Alley, Rignot, Bamber, Velliconga): Alley (best Woody Allen impression). Starts with IPCC TAR: not much from ice sheets in next 100y, though considerable uncertainties, and its a difficult topic. Then: now, it looks like mass loss is starting, 100y ahead of schedule. “not a run for the hills we’re getting flooded thing” but “we don’t know whats coming” but poss of metres of SLR in centuries not decades. Rignot: greenland glaciers: Angmagssalik; warming now is about what it was in the 1920′s; don’t know if they accelerated then. Then mentions Ant warming and ice shelf collapse and speed up of glaciers there. Uncertainties. Pine Island.

Then I had to leave to talk about UAV’s; about which I know rather little, but someone gave me the talk to give.

Bit of solar (not really serious…) then onto the seaice session, which is packed out, probably because its headlined with “explaining the recent decrease”. Normally its a bit of a specialist subject. Zhang gives the invited talk (but at EGU, even invitied talks are often only 15 mins, inc questions) and whilst there is some interesting analysis in there, he gives the bottom line as basically the sea ice has retreated because its got warmer. Small interesting point: he seems a big decrease in 1989, when a shift in the wind forcing cleared a lot of old ice out, which he labels a potential “tipping point”. Ah how I love that phrase.

Curiously, the session stays packed for subsequent talks: usually it empties after the invite. Someone else does a basic analysis of the AR4 runs for their arctic state and the winner is… HadGEM1! Hurrah for the UK and the two A’s.