Health and Climate Change
Authors: Watts Nicholas 
Published: May 2016

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Environmental Science. Please check back later for the full article.

There are three important linkages to explore between climate change and health in terms of potential policy responses. The first of these linkages relates to the impacts on health resulting from climate change. In 2009, The Lancet described climate change as “the greatest global health threat of the 21st century,” referencing the direct and indirect effects it is having on public health. While a number of impacts are directly observable (i.e., an increased frequency and severity of many extreme weather events), others are more indirect, being mediated through environmental and social systems (i.e., the health complications associated with mass migration or violent conflict). Further, it is well understood that resilience and adaptive capacity play an important role in reducing these impacts—often leaving low-income communities worse off than most.

The second important linkage between climate change and health relates to the co-benefits of mitigation and adaptation. Policy responses to climate change will inevitably come with both intended and unforseen externalities and “side-effects” (both positive and negative). Traditional public health tools, such as health impact assessment, can be valuable in identifying and understanding these co-benefits to better guide policy. Indeed, many of the mitigation solutions yield substantial benefits for public health: switching away from coal-fired power plants as an energy choice improves cardiovascular and respiratory health; designing cities which are cycle- and pedestrian-friendly increases rates of physical activity (helping to tackle obesity, diabetes, many cancers, and heart disease) while also reducing greenhouse gas emissions from vehicles.

Finally, the health system itself has an important role in responding directly to climate change. This is frequently understood in terms of a health facility’s ability to withstand and respond to the impacts of climate change, and to the adaptive capacity of the health system itself. But there is also a role for the health system to play in reducing its own emissions. In countries like the United Kingdom and the United States, the formal health system is responsible for as much as 3–8% of national emissions, and has subsequently made commitments to reduce its environmental impact. A 2013 review of the UK National Health Service’s carbon footprint indicated that as much as 60% of this came from procurement, 17% from building energy, and 13% from health system–related transport. A number of the solutions available are often designed in a way that improves patient outcomes and satisfaction, while reducing the costs of healthcare. In low- and middle-income countries, the focus is placed on ensuring access to reliable electricity, a task well suited to decentralized micro-grids with sustainable power generation.

Academic literature on the topic of health and climate change has expanded rapidly in recent years and includes the 2009 and 2015 Lancet Commissions on health and climate change, the 2010 series on the health co-benefits of mitigation, and the 2014 Intergovernmental Panel on Climate Change’s 5th Assessment Report.