Elizabeth Farrelly's recent article in The Sydney Morning Herald sets out very starkly the big difference between a 2 degree and 4 degree shift in global temperatures.
"Four degrees is huge. Four degrees is runaway climate change, all the tipping points... Simply, we have to become fossil free. No more oil. No more gas. And not just no new coalmines. No coal, period."
We agree with her opinion that we need to jump before we're pushed.