Senckenberg Research


In this project simulations with regional and global climate models are carried out for different tipping points of the climate system in order to answer the following questions:

1) Are the tipping points regionally restricted or do they indicate a global climate change?

2) Is it possible to reconstruct tipping points with climate model experiments?

3) Is it possible to identify the mechanisms that have led to a "tipping"?

In order to answer these questions, ensemble calculations are simulated with the global climate model ECHAM6 and for specific regions that are investigated in the joint project (Kyrgyzstan, Indian monsoon, East Asian monsoon) with the regional model COSMO-CLM. For modeling, certain periods of time from the Holocene are selected from which significant tipping points are known. The focus of the analysis is on the interplay of the NAO (North Atlantic Oscillation) and the monsoon, the interplay of ENSO (El Niño Southern Oscillation) and the monsoon as well as on the linkage of the monsoon with the meanders of the westerly jet stream over Central Asia.

The model calculations are compared with the proxy data obtained within the joint project as well as already published data. The model data are then used to identify the processes which lead to a tipping point and to evaluate whether they are isolated or systematic metastable changes of the climate system.