1990 emissions

The ETM compares future CO₂ emissions to 1990 emission levels, as this is a common reference point in (inter)national climate policy. In contrast to the present and future scenario year, the 1990 emissions number is not calculated (dynamically) by the model, but instead is a fixed input number researched for each region. You can view the CO₂ emissions of your scenario compared to 1990 by clicking on the dashboard item 'CO₂ relative to 1990'. This page explains which data is used within the ETM and how 1990 emissions are calculated per area.

Checkout: The 1990 emissions of other green house gases is currently not included in the ETM. The method described below is about CO₂ only.

Country-level data

For all countries in the ETM, the 1990 emissions number is based on data from the European Environmental Agency. The following categories are included:

UNFCCC Emissions Category	UNFCCC Code	ETM Type
Fuel Combustion by sector	1.AA	Energetic
Ammonia Production	2.B.1	Non-Energetic
Metal Industry	2.C	Energetic
Waste Incineration	5.C.1	Energetic

For non-energetic emissions, the ETM only takes the non-energetic emissions during the production of ammonia in the fertilizer sector into account in the 1990 emissions. This is because the non-energetic emissions in the fertilizer sector can be calculated in the ETM (for the start and future year) using valid generic assumptions, which allows for a credible comparison of the 1990 emissions and the start and future year in this category. Non-energetic emission in other sectors can be more site-specific and therefore more complex and inaccurate to model. Therefore, the ETM does not take non-energetic emissions of other sectors into account.

Regional-level data

For regional datasets, no uniform, international source exists detailing historic emissions on a fine-grained geographical level. As such, 1990 emissions are researched for each region individually.

For subregions of the Netherlands, data is used from RIVM. They report 1990 emissions on a municipality level. However, this data does not comply with the main principles of the ETM's CO₂ calculation:

• Emissions are reported by geographical location. This means that a municipality with a power plant within its border is assigned the full emissions of the plant. Conversely, no emissions for electricity use are taken into account for municipalities without power plants.
• The regional data does not conform to IPCC definitions. This means that emissions of biomass are included.

Correction method

To be able to compare 1990 emissions to the present and future emission levels calculated by the ETM, the following data correction is applied:

• First, for all municipalities 1990 CO₂ emissions are calculated for all sectors except the energy sector
• Secondly, each municipality total is divided by the Dutch total, both excluding energy sector emissions. This results in a 'scaling factor' per municipality. For example, municipality X has 3% of total Dutch 1990 emissions excluding the energy sector.
• Finally, this scaling factor is multiplied with the total Dutch 1990 emissions including the energy sector to obtain an estimate per municipality.

This results in an estimate of the full 1990 municipality emissions that is in compliance with the ETM principles. This method implicitly assumes that the 1990 Dutch energy sector emissions can be allocated to a municipality level proportionally to a municipality's non-energy sector 1990 emissions.

Two caveats apply to this method, making it difficult to assess the quality of the outcomes:

• For several sectors, the RIVM source data is based on estimates rather than measurements.
• The above method has not been tested extensively, due to a lack of reference data.