How on earth do we combat climate change?

The greatest risk to human health is neither communicable nor non-communicable disease, it is climate change. Saying this, as I and others have started doing at conferences, seems to take a certain courage. We’ve been emboldened by clear statements from WHO’s director general Margaret Chan and from the Lancet (www.thelancet.com/climate-change). But this week, at a meeting hosted by the BMJ in collaboration with an extraordinary alliance of organisations (http://climatechange.bmj.com, doi:10.1136/bmj.d6775), it became clear that we are going to have to get braver still.

Let me begin by acknowledging that putting climate change at the top of the list of things to worry about is hard when faced …