Precision and uncertainty in emissions calculation models
This Explainer report covers the context and concepts of Greenhouse Gas (GHG) accounting and emission calculation model precision, uncertainty, and materiality. It shows:
- There is a difference between measuring and modelling greenhouse gas (GHG) emissions. Whilst measuring determines the exact amount of GHG emitted, modelling is a simplification of measuring physical processes.
- A model requires a single variable activity data multiplied by an emissions factor (EF).
- Emission factors help us understand the level of greenhouse gases intensity that occurs from certain activities. They have a certain level of accuracy and uncertainty.
- Toitū sources or develops emission factors additional to those published by government agencies, including to improve accuracy.
- Carbon accounting might not give a precise representation of GHGs being emitted, but it does equip organisations with vital insights into their climate impact and areas of influence. If it isn’t measured, it cannot be managed.