The UN Intergovernmental Panel on climate change has released its latest report. This Sixth Assessment Report is a weighty document at nearly 4000 pages and the science is described as robust. It has been tagged "code red" because human activity is changing our climate in unprecedented ways. A key word for the whole report, according to Will Steffen an Australian climate systems scientist, is "urgency". We have this current decade to act and to do so decisively. To shift all human activity and the global economy to a low-carbon footing is the task before us. There can be no new coal, gas or oil developments and existing fossil fuel extraction has to be phased out. 2030 is a key d...