Climate change has modified temperature and stratification and consequently affected the ecosystems of lakes on a global scale. These effects are expected to be further amplified in the future. We are investigating these changes and their causes by:
- analysing the heat budgets of lakes and their sensitivity to climate factors both for individual lakes and at the global scale;
- detecting existing trends in lake temperature and thermal structure and the causes of these trends using data analysis and modelling tools;
- projecting changes of the thermal structure of lakes for a range of climate scenarios using numerical models.
Investigations are done both at the national scale, for example within the Hydro CH2018 project, and in international collaborations within the Global Lake Ecological Observatory Network (GLEON) and the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP).
As an example, the figure below shows the projected probabilities for a specific day of the year of Sihlsee to be stratified or ice-covered, and to reach oxygen concentrations below the legal threshold of 4 mg/L for the current climate and the IPCC A2 scenario (based on Kobler et al., 2019)