Switzerland has a novel platform for drought warnings

Dry periods are a growing problem in Switzerland for the water, land, and energy sectors, and thus for the general population. Periodic water shortages also have a negative impact on our forests and forestry. In order to systematically monitor and predict drought conditions in Switzerland, the Federal Office for the Environment (FOEN), the Federal Office of Meteorology and Climatology (MeteoSwiss), and the Federal Office for Topography (swisstopo) together with the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) and other supporting institutions have jointly developed an early warning system. This system became operational throughout Switzerland on May 8, 2025.

Link: Drought warning platform

The drought information platform (www.trockenheit.ch) supplements the federal government’s existing services in the area of information and warnings about natural hazards and implements the Federal Council’s mandate of May 18, 2022.

The drought platform provides uniformly prepared information on the current drought situation in the various regions of Switzerland and forecasts for the next four weeks. Data on past events is also available. To this end, existing measurement networks and forecast models have been supplemented with new information from satellite data and long-term forecasts, e.g. for precipitation. From 2026, measurement data on soil moisture, water temperatures, and forest water deficits should also be integrated.

TreeNet collaborates with the drought platform and collects biological drought indicators such as the water deficit of trees, which is measured every 10 minutes on around 700 forest trees throughout Switzerland. The data are turned daily into drought and growth signal. TreeNet is one of the few networks that can automatically measure vegetation data directly on plants. Most information about vegetation comes from satellite data, which can only provide limited daily drought information and is mostly based on models that are difficult to validate. Forests are ideal as general models for drought because they are hardly influenced by short-term management interventions such as agricultural use. Increasing drought in forests is considered a reliable, general indicator to quantify how air and soil dryness affects different Swiss landscapes.