“The scientific evidence is now overwhelming: climate change is a serious global threat, and it demands an urgent global response.” This was the unequivocal message of the Stern report, published by HM Treasury last year.1 The time for debate is over—at least about whether climate change is potentially catastrophic and caused by human activity. But who should act and how? This week, the BMA Board of Science publish their report Health Professionals—Taking Action on Climate Change.2 It outlines the basic facts and figures and points to copious sources of further information.

The report endorses Stern’s conclusion that, “urgent action is needed now at an individual, organizational, political and global level.” It summarises evidence about cause and effect, then considers the health implications. A diagram (from the Lancet) points to floods, storms, and other forms of environmental damage leading to “impaired nutrition, health, survival.”

Turning to how the effects of climate change can be reduced, the …