AL (and V1S, sorry!) pointed me to http://www.esrl.noaa.gov/gmd/aggi/, which lead me to http://www.esrl.noaa.gov/gmd/ccgg/iadv/, from which I selected Barrow, as being in the Arctic, and CH4, as being methane, and 2000-2008, as being a small enough interval that you can see whats going on, and I got:
So there you have it: methane isn’t shooting up precipitously. Its a bit higher this year than last. OK, I know, those are preliminary data. But I think thats enough to rule out any major changes.
Its worth pointing out (JA has said this, but I forget where) that methane is an awful long way below the “std” BAU scenarios. I can’t find a recent one now, but the IPCC ’90 BAU scenario would have us at about 2200 ppbv by now.
BTW, Nuture says that CO2 [corrected] *emissions* are now increasing at 3.5 % a year, which is higher than it was. Don’t immeadiately know what concentrations are increasing at.
[Update: Small side note: here we have Nature linking to wiki. I didn't know they did that -W]