My interests lie in the application of atmospheric science to policy on air quality, the relationship between air quality and health, and on the linkages between air quality and climate change. I have a particular interest in the effectiveness of air quality policies on urban and regional air quality as evidenced by measurement. Recent studies on NOx trends are a good example.

My interests lie in the application of atmospheric science to policy on air quality, the relationship between air quality and health, and on the linkages between air quality and climate change. I have a particular interest in the effectiveness of air quality policies on urban and regional air quality as evidenced by measurement. Recent studies on NOx trends are a good example.

Further interests include the establishment of more detailed relationships between air quality and health in the UK as part of projects funded by the MRC at the MRC-HPA Centre at King's College. Prior to joining Defra (see below) I carried out air quality impact assessments prior to developments at three major UK airports – Heathrow, Gatwick and Stansted, and have maintained an interest in the impact of aviation on air quality.

I have a continuing interest in ozone as a pollutant and was the first to demonstrate the impact of stratospheric air on ground level concentrations in the UK. I developed a simple, fast but accurate model used in the daily government air quality forecast for ozone.

I was until recently head of the air quality programme in Defra responsible for air quality policy and research to inform it. I currently chair the Executive Body of the UNECE Convention on Long Range Transboundary Air Pollution, and chair the Modelling Review Steering Group for Defra. I am lead author of policy section of the UNEP Assessment of Short Lived Climate Forcers.