Methodology

The NAEI is compiled on an annual cycle that encompasses: data collection, compilation, reporting, review and improvement. Each year the latest set of data are added to the inventory and the full time series is updated to take account of improved data and any advances in the methodology used to estimate the emissions. Updating the full time series, making re-calculations where necessary, is an important process as it ensures that:

  • the full NAEI dataset is based on the latest available data, using the most recent research, methods and estimation models available in the UK
  • the inventory estimates for a given source are calculated using a consistent approach across the full time-series and the full scope of pollutants
  • all of the NAEI data are subject to an annual review, and findings of all internal & external reviews and audits are integrated into the latest dataset

Example Inventory Cycle

Inventory Cycle

Page last modified: 03 August 2022