Climate change: Social determinants of global warming over the 21st century

How perceptions of climate change, the cost and effectiveness of mitigation strategies, and political responses all interact to determine the course of global warming over the 21st century, are uncovered in a modelling study published in Nature. These findings — revealed through the analysis of 100,000 possible future policy and emissions trajectories — highlight the importance of considering fundamental interactions between the climate and our society in climate change modelling.

Complex interactions exist between the climate and our society; interplay between social, political, economic and technical systems can affect the trajectory of greenhouse gas emissions. However, their combined impacts on future emissions and temperature scenarios have yet to be thoroughly investigated, despite forming the context in which policies may arise.

Frances Moore and colleagues simulate 100,000 possible future trajectories of emissions and policies using an integrated, multidisciplinary model connecting data across a wide range of social, political and technical fields. These pathways can be divided into five groups, in which global warming in 2100 varies between 1.8 °C and 3.6 °C above average temperatures between 1880 and 1910. The authors reveal several important factors that could influence potential future variations in trajectories and subsequent warming over the 21st century. These factors include how the public perceive climate change, the costs and effectiveness of mitigation technologies, and the responsiveness of political institutions.

The authors conclude that complex connections between different social, political and technical factors could be influential in determining the emergence and future course of climate policy and emissions outcomes. Identifying the extent of this influence requires a distinct approach that treats these emissions and policy trajectories as outcomes of, rather than inputs to, integrated climate–social models.