Amanda Lynch from Monash University's 'Climate Program' writes a 3/4 page op ed in The Age this morning criticising the Garnaut Review's draft report on 'Targets and Trajectories' for setting excessively high greenhouse gas emission targets of 450 ppm. Unfortunately this claim seems wrong - Garnaut targeted 550 ppm and the criticisms she makes should relate to this target. Garnaut rejects the 450 ppm target as infeasibly low. For example, at 550 ppm, not 450 ppm as Amanda claims, there is only a 50% chance of restraining temperature rises to 2oC.
I have criticised aspects of the Garnaut proposals - though as I reread his report my attitudes are softening somewhat - but it is important for Amanda to get her facts right.
The positive claim in the Garnaut argument that needs to be critically tested is the view that to cut emissions to 450 ppm would impose impractically huge cutbacks on developed countries given the expectation of continued high emissions growth in developing countries. That's the point where I become ambivalent. Is it better to target something modest but achieveable but which still carries the prospect of catastrophe or should we target something much less feasible which substantially reduces the prospect of catastrophic change?