Anthropogenic climate change has been described as the greatest threat to global health in the 21st century. Our planet is expected to continue to warm over the next 100 years and this will result in changes to our weather in New Zealand. This review summarises a number of health risks projected from a changing climate that could impact on future generations.
The result of projected changes in climate are most likely to worsen environmental health risks that already exist including: exposure to air irritants and pollutants, extreme weather events, exposure (or lack of) ultra-violet solar radiation, potential establishment of vector-borne diseases and illnesses related from exposure to toxins, water-borne and infectious diseases. Future rises in sea level will amplify some of these issues. New risks are more likely to occur under high heat-trapping or greenhouse gas emission scenarios. There are also a number of indirect impacts on health such as increased water and food insecurity and population migration.
The effect on our health will depend on a number of factors: the level of severity will relate to heat-trapping gas emissions in the future; how both heat-trapping gas emissions and current environmental risks are managed (mitigated); and how prepared the Government, public and the health sector are in terms of management of projected impacts (adaptation). A range of adaptation mechanisms (eg, early warning systems) exist to cope with these effects which are discussed in this review. Many are already employed in New Zealand, such as surveillance, public education and civil defence alerts. These will remain important tools to reduce environmental health risks.
Some knowledge gaps were also found that relate to the impacts from short-term, prolonged and new environmental health risks. Understanding those gaps and the direction of future studies will be critical to informing adaptation planning and policy and to reduce future climate related risks to health. Many adaptive responses, encompass co-health benefits, benefits that go beyond those that the adaptive measures will bring. These “win-win” opportunities will benefit all New Zealanders immediately, regardless of the future.