EMEP/EEA Guidebook: A.8 Projections

Projections are a tool to assess what might happen if countries take (or had taken) no action (‘without measures’ (WOM)), what might be achieved with actions that countries are committed to (‘with existing measures’ (WEM) or sometimes simply known as ‘with measures’ (WM)) and what else could be done (‘with additional measures’ (WAM)). These three scenarios should be assessed using the same set of exogenous economic projections. Projected estimates will therefore need to be able to reflect the impacts of relevant policies and measures to assess whether or not the policies in place are far reaching enough for emission targets to be met.

However, emission projections are inherently much less certain than the historical emission inventory, since they require additional assumptions about future growth in activity (e.g. production, transport, population) and technology uptake.

This chapter is designed to provide general guidance on projecting emissions to accompany national inventory reporting under the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP Convention), the EU’s National Emission Ceilings (NEC) Directive (EU, 2016) and reporting of the national air pollution control programmes (Article 6 of the NEC Directive).

The material is intended both for countries establishing projected emission estimates for the first time and for countries with established projection approaches. This chapter covers:

• the terminology used in projections and projections reporting;
• the methods used to project emissions;
• guidance on tackling common problems associated with gathering appropriate data on emission factors and activities and ensuring consistency with historical emission inventories.

Sector-specific projection issues are described in Annex 1 of this chapter; detailed information on historical inventory compilation can be found in the sector-specific chapters of this Guidebook.