Understanding changes in the UK's CO2 emissions: a global perspective.

The UK appears to be a leading country in curbing greenhouse gas (GHG) emissions. Unlike many other developed countries, it has already met its Kyoto obligations and defined ambitious, legally binding targets for the future. Recently this achievement has been called into question as it ignores rapidly changing patterns of production and international trade. We use structural decomposition analysis (SDA) to investigate the drivers behind annual changes in CO(2) emission from consumption in the UK between 1992 and 2004. In contrast with previous SDA-based studies, we apply the decomposition to a global, multiregional input-output model (MRIO), which accounts for UK imports from all regions and uses region-specific production structures and CO(2) intensities. We find that improvements from "domestic" changes in efficiency and production structure led to a 148 Mt reduction in CO(2) emissions, which only partially offsets emission increases of 217 Mt from changes in the global supply chain and from growing consumer demand. Recent emission reductions achieved in the UK are not merely a reflection of a greening of the domestic supply chain, but also of a change in the international division of labor in the global production of goods and services.