The British government has claimed that UK-wide carbon emissions have declined by five percent since the early 90's - an impressive achievement that appears to validate the idea that economic growth need not involve increased emissions, a key tenet of climate policy.

But a new report from the University of York's Stockholm Environment Institute (SEI) says that these emissions were merely exported, not reduced - and that, when emissions from shipping, aviation, and imported goods are included in the tally, the UK is actually up by 18 percent.

The report is an unfortunate blow to the credibility of the UK's government policy, but it's an important reminder that emissions reductions have to be calculated inclusively and fairly. Shipping, aviation, and imported goods are omitted from carbon trading schemes, but that makes their impact - together a significant chunk of a nation's carbon budget - no less real. The fact that the point source of those emissions were in China or India, or from a container ship bringing imported goods, makes them no less relevant to the UK's carbon budget.

That said, the UK's within-country emissions really have been reduced by 5 percent, and that figure should stand apart from "exported" emissions. We'd argue, then, that a more complete and informative accounting would include figures for the country itself and for the embodied emissions of its imported and transported goods. This would tend to paint a more accurate picture of how a country is affecting the climate. Such an accounting would treat more fairly those industrialized developed countries whose carbon emissions are largely in the service of production for export, while serving as an incentive for developed countries to reduce the embodied energy of the goods they consume while also reducing "native" emissions.