An Atmospheric Emissions Indicator to Implement Air Quality and Climate Change Targets

This paper introduces a technique for assessing the progress towards air pollution and greenhouse gas targets. To guide policy decisions, an atmospheric emissions indicator, AEI, combining national air quality and greenhouse gas emissions, is proposed. It has been applied to the UK, but could be adopted by other countries. Although not directly a measure of environmental consequences, this index is a simple policy aid to implementing air pollution and climate change targets based on an emission ceilings approach. The proposed AEI index is a weighted sum of emissions derived from modelling studies of the impact of UK air pollution and greenhouse gas emissions between 1970 and 2050. The approach is not so very different from aspects of current UK legislation, such as the National Emissions Ceilings Regulations, the UK Climate Change Act, National Determined Contributions within the Paris Agreement, and other assessment tools of population exposure, such as cost-benefit analyses and other environmental targets. The indicator could be extended to incorporate very short-lived radiative forcers associated with air pollution.