Assumptions underlying the CEF package

In case the acronym hasn’t stuck yet, CEF means Clean Energy Future. If I’d said “carbon tax”, no problems.

In my 2009 submission to the Senate Select Committee on Climate Policy I ripped into the Rudd Government for commissioning Ross Garnaut

to analyse two specific stabilisation goals: one at which greenhouse gases are stabilised at 550 ppm CO2-e (strong global mitigation) and one at which they are stabilised at 450 ppm CO2-e (ambitious global mitigation).

I then castigated Garnaut for accepting the brief:

This is sad and actually outrageous. Garnaut, had he acted responsibly at this point, would have gone back to those who commissioned the report and asked for the reference to be changed so that he could develop a strategy for a safe climate.

When the 2050 target was changed from a 60% reduction in emissions relative to 2000 to 80% I wondered whether the assumptions about the science had changed. If you go to the Treasury Report on modelling a carbon price it becomes clear that nothing has changed.

Treasury modelled two scenarios, one called “medium” and the other “ambitious”. The medium scenario is then called “core”. If adopted worldwide, it aims to stabilise greenhouse gas concentration levels at 550 parts per million. The ambitious scenario aims at 450ppm.

Treasury then blithely tell us that 450ppm will give us a 50:50 chance of keeping the average global temperature at less than 2C above pre-industrial levels, while 550ppm raises that figure to 3C. Stabilisation at 2C, they say, is the threshold for “dangerous” climate change. They then calmly tell us the likely implications of a 3C rise: Continue reading Assumptions underlying the CEF package