MeteoSwiss and ETH Zurich publish 2025 Swiss climate scenarios

The Federal Office of Meteorology and Climatology (MeteoSwiss) and ETH Zurich presented the 2025 climate scenarios to inform the Federal Council’s strategy on adaptation to climate change.

• Main announcement (presentation): On 4 November 2025, MeteoSwiss and ETH Zurich presented the 2025 climate scenarios (event attended by Federal Councillor Elisabeth Baume‑Schneider) that update and expand the 2018 scenarios; key quantified findings include Switzerland warming 2.9 °C above pre‑industrial levels by 2024 (global: 1.3 °C), projected ~4.9 °C local warming under a 3 °C global scenario, the hottest day +4.4 °C, Zurich ~5× more tropical nights, a typical summer drought +44% intensity, and a winter zero‑degree line rise of 550 metres to ~1,450 m.
• Background and implementation details: The scenarios were developed by MeteoSwiss, ETH Zurich and C2SM, with input from OCCR (University of Bern) and University of Lausanne, under the NCCS; they are a regularly updated centralised resource for the Federal Council’s adaptation planning, illustrate impacts at different global warming levels (referencing the Paris Agreement targets) and note that global net‑zero by 2050 would avert most long‑term additional warming.