Switzerland

Historical emissions data for 1990-2022 are taken from the April 2024 update of Switzerland’s GHG inventory (Bundesamt für Umwelt BAFU, 2024b).

We calculated the 2030 targets using the most recent national inventory (Bundesamt für Umwelt BAFU, 2024b).

Switzerland has not officially communicated the domestic share of its NDC target and has removed any specific information from the current version of the CO₂ Reduction Act. In a previous draft from 2021 it stated that 33% (66% of 50%) of emissions will be reduced domestically (by 2030 below 1990 levels). From other official communication documents, it becomes evident that there is a consensus by the Federal Council that at least 30% will be reduced within the borders. After proposals for a 75% and a 70% (of the 50%) reduction were rejected in parliament in 2024, the Environment Minister Albert Rösti announced that he would propose a 66% share to the Federal Council (Das Schweizer Parlament, 2024). Due to a lack of clearer information, we have therefore decided to take a range between 30% and 33% by 2030 below 1990 levels as Switzerland’s domestic share.

Switzerland’s NDC includes LULUCF. The NDC states the desire to use a reference level for forest land, while emissions for other land uses will be included both in the target and baseline years. To assess LULUCF emissions in 2030, we take an average between the two projections WEM (with existing measures) and WAM (with additional measures) as to reach the 2030 target the emissions reduction pathway would need to be in between the two scenarios. Since there is some uncertainty on both the accounted LULUCF emissions and the target itself, we show the target as a range, with the lower end of the range representing emission levels of 33% reductions without the accounted LULUCF emissions.

For our current policy projections, we use a study be the Zurich University of Applied Sciences (ZHAW), which is the only scenario analysis identified that quantifies the impacts of the new RE Act of June 2024 (Rohrer et al., 2024). The study builds on the modelled Energy perspectives 2050+ (scenario WWB) (Bundesamt für Energie, 2022), which are also used for the “with existing measures” scenario submitted to the UNFCCC in Switzerland’s 5th Biennial Update Report (Swiss Federal Office for the Environment, 2022). The projection is then harmonised to actual 2022 emissions from the most recent national inventory (Bundesamt für Umwelt BAFU, 2024b).

In its ZERO-basis scenario of the Energy perspectives 2050+, the Swiss government provides assumptions on their estimated residual emissions to meet its 2050 net-zero GHG target. The CAT approach assumes full implementation for all CDR and CCS planned for the target year, meaning that residual emissions are determined by the level of LULUCF emissions (zero assumed for Switzerland) and international offsets to compensate. Hence, the scenario “NET-ZERO scenario (EP2050+) incl. international offsets” was used, which assumes 4.7 MtCO₂e of residual emissions in Switzerland in 2050 (Bundesamt für Energie, 2022).

The CAT uses Global Warming Potential (GWP) values from the IPCC’s Fourth Assessment Report (AR4) for all figures and time series. Assessments completed prior to December 2018 (COP24) used GWP values from the IPCC’s Second Assessment Report (SAR).