The graph below shows relative improvements in carbon dioxide emissions for four countries (from the U.S. Energy Information Agency) per national GDP (as measured in PPP terms and reported by Maddison). The data starts in 1991, selected because it is the first year that the EIA reports total emissions for reunified Germany.
The graph shows some interesting, and to me at least, surprising things.
First, even though Japan is very efficient, it has made little to no progress is reducing carbon dioxide per unit of GDP.
Second, Germany and the United States show very similar total gains
in reducions of carbon dioxide per unit GDP, though Germany is more
efficient in absolute terms. If Europeans climate policies have a
signal in emissions per GDP, you certainly can't see it in this data.
Third, less surprising to regular readers of this blog, China has seen a rapid increase in carbon dioxide per GDP since 2000.
