This Theme in the National Centre for Earth Observation aims, by developing an integrated approach to the analysis of satellite measurements, to provide new information on atmospheric composition and aerosols for air-pollution forecasting and testing climate models.

Its priorities are to:
- Generate data on trace gases and small particles, both natural and man-made, also known as aerosols, in the troposphere (0-11km) and the lower stratosphere (around the altitude commercial jets fly)
- Improve understanding of where these gases and particles come from and how they move in the atmosphere
- Test the UK's chemistry-climate model
- Work with governments across Europe to help monitor pollution and forecast air quality