An additional complicating factor is that serious attempts at reducing CO2 emissions would  4  I asked our econometricians to test the hypothesis that the observations over the past few years were drawn from the same process as generated the observations over the 20th century.
Their answer, based on a battery of suitable tests for a univariate time series, was that it was too early to tell. 4  BIS central bankers’ speeches  probably change the story at some point. The lessons of history, moreover – that booms don’t go on indefinitely – are also too great to ignore.