Carbon offsetting accreditation?

Buying carbon offset is a bit of a minefield, in that it's an unregulated industry and it's hard to know that what you're buying makes either sense or a difference. Tree-planting is all well and good, but does it have a long-term impact? And would the development projects in which you can invest happen without you anyway, in which case what is your money achieving?

Then there are the sharks in the water -- I heard a lovely interview with a chap from HSBC a while back, in which he related that when word got around that the bank was planning to go carbon-neutral, he had calls from people offering to sell him swathes of the Amazon rainforest. He expressed... shall we say 'polite suspicion'? -- that the land was theirs to sell in the first place.

It's somewhat surprising that, as far as I can tell, there's no accreditation scheme for offset projects. If the RSPCA can manage the 'Freedom Foods' project, the Soil Association can do the whole organic thing, and there are more standards in the electronics world than you can shake a USB cable at -- you'd think somebody with a recognisable brand would have this covered. But evidently not, or at least, not yet.

It's encouraging, then, that the Commons environmental audit committee is to investigate personal air travel offset schemes. Compulsory accreditation or regulation at the UK or European level is on the agenda, as is requiring flyers to offset the emissions they cause. Hurrah!