Abstract:

We are sitting in an enormous cathedral. Light is shining in, there is much light. From high up in the middle of the cathedral a green leaf floats down, slowly, slowly floating down. If carbon dioxide emissions were maintained at today’s levels (an optimistic assumption), they would lead to a nearly constant rate of increase in atmospheric concentrations for at least two centuries, reaching about 500 ppmv (approaching twice the pre-industrial concentration) by the end of the 21st century . . . the increase in global average surface temperature at equilibrium resulting from a doubling of CO2 would be likely to be between 1.5 and 4.5 ºC (IPCC).

Author: Simon Mason