Why New Zealand must rapidly halve its greenhouse gas emissions.

New Zealand must commit to substantial decreases in its greenhouse gas emissions, to avoid the worst impacts of climate change on human health, both here and internationally. We have the fourth highest per capita greenhouse gas emissions in the developed world. Based on the need to limit warming to 2 o C by 2100, our cumulative emissions, and our capability to mitigate, New Zealand should at least halve its greenhouse gas emissions by 2020 (i.e. a target of at least 40% less than 1990 levels). This target has a strong scientific basis, and if anything may be too lenient; reducing the risk of catastrophic climate change may require deeper cuts. Short-term economic costs of mitigation have been widely overstated in public debate. They must also be balanced by the far greater costs caused by inertia and the substantial health and social benefits that can be achieved by a low emissions society. Large emissions reductions are achievable if we mobilise New Zealand society and let technology follow the signal of a responsible target. The New Zealand Government has announced a 2020 greenhouse gas emission target of 10–20% below 1990 levels, 1 leading into international climate change negotiations culminating in Copenhagen on 7-18 December. 2,3 This target range has strict conditions attached and, unlike many developed nations, New Zealand has not offered an alternative emissions target if these conditions are not met. 4,5 We consider New Zealand needs to do much more to adequately respond to the climate change threat. We summarise why health professionals should care about this problem, and why it is our duty (to our patients and the wider public health) to act now, before it is too late.