The evidence

The Intergovernmental Panel on Climate Change has stated that the ‘warming of the climate system is unequivocal’, and that ‘man’s influence on the climate is clear’. These climatic changes place further pressures on our ecosystems, which are already feeling the strain of the world’s growing population, and the associated increased demand on resources.

Indeed, climate change and its health impacts are already being experienced today, and are likely to prove catastrophic if left unabated. These effects include an increase in frequency and severity of extreme weather events such as floods, droughts, extreme storms and heatwaves, which have both physical and mental health impacts; the spread of vector-borne diseases such as malaria and dengue to new locations; worsening nutrition resulting from decreased agricultural productivity and higher global food prices; rising sea levels and associated population displacement; and an exacerbation of poverty. These health impacts have been summarized and studied extensively by the IPCC’s second working group and by the 2015 Lancet Commission on Health and Climate Change.

Through processes such as these, climate change threatens to undermine the foundations of public health and wellbeing, both globally and in the UK. If we fail to act quickly, it will exacerbate existing national health challenges, place undue financial strain on the NHS, and worsen health inequalities both within the UK and internationally.

Responding to climate change

Many of the key drivers of climate change – fossil fuel energy, unhealthy diets, and poorly designed cities which make us reliant on cars rather than active transport – also cause poor health directly through air pollution, high saturated fat intake, and physical inactivity. Hence, by responding to climate change, we can simultaneously address these health challenges, making many climate change policies cost-effective and sensible public health interventions. Similarly, health system strengthening and other measures to improve community health is one of the most effective adaptation strategies to minimise the harm to health caused by climate change.

Protecting health into the future depends on embedding actions on mitigating climate change and the principles of sustainable development across government policy and into everything that we do, as health organisations, as health professionals, and as citizens. There is clear and widely accepted evidence that inaction will lead to unacceptable risks. The science is clear; the legal and implementation frameworks are becoming aligned; a national cross-system strategy for the health and social care sectors exists; and the multiple benefits for health if we take action now are profound.

The overwhelming evidence on the health case for action led the 2015 Lancet Commission on Health and Climate Change to conclude that “tackling climate change could be the greatest global health opportunity of the 21st century”.

For a comprehensive overview of the links between public health and climate change, read the Commission here (registration required).