Alistair Woodward is a Professor in Epidemiology and Biostatistics at the University of Auckland. His interests in environmental health have touched on tobacco, road crash injury, ionizing and radiofrequency radiation and the consequences of transport policy. He was a convening lead author on the 5th assessment report of the IPCC. His book “The healthy country? A history of life and death in New Zealand” was published at the end of last year.

He will present findings from a project sponsored by the UK Foreign and Commonwealth Office. Critical temperature thresholds for human health are based on exposure standards, guidance notes and well-established physiological requirements. Climate projections are provided by the UK Hadley Centre based on plausible high-end emissions scenarios running from the present to 2200. Study areas include northern India, southern China and south-east United States. Probability versus time projections will be presented for three endpoints: heat that prevents outdoor competitive sport; conditions incompatible with moderate to heavy labour; and, extreme heat that is not survivable.

The latest IPCC assessment AR5 concluded that climate change should be framed primarily as a risk management issue. There are important differences between this and the usual emphasis in science on error-free prediction. Instead of concentrating on what is likely and what is most certain, the question becomes: what do we want to avoid? In other words, what risks would be intolerable? When and where would these extraordinary risks be encountered, if warming continues at the present rate?