The graph above is from a report (PDF) of the UK government’s National Audit Office, which explains some of the difficulties in accounting for carbon emissions at the national level.

The report has received some attention for this figure and what the following passage means for emissions reduction targets currently under consideration by the UK Parliament:

Figure 13 demonstrates that there have been no reductions in UK carbon dioxide emissions if measured on the basis of the Accounts rather than on the basis of the IPCC/Kyoto reporting requirements.

One point worth making is that the difference between UK Environmental Accounts and Kyoto accounting stems from international aviation and shipping (not included by Kyoto) and the treatment of tourists and nonresidents in the UK. These sort of issues obviously play a large role in the ability of countries to meet Kyoto targets. One wonders what the effect on the ability of countries to meet Kyoto targets would be if carbon emissions were accounted for on an UK Environmental Accounting Basis.

It would seem that the passage of ambitious targets and timetables for UK emissions reductions has been made less likely by this report, and yet at the same time it can’t be good news for those wanting that third runway at Heathrow.