Climate shapes vegetation, and vegetation in turn changes climate, for example, by soils and plants reflecting sunlight differently or by plants cooling an otherwise dry environment through transpiration. The Climate Vegetation Dynamics Group aims at understanding these terrestrial biogeophysical feedback processes in the Earth's climate system. To this end, we address the following questions: How has the interaction between the atmosphere, vegetation, land surface, and ocean evolved in the past and how might it evolve in the future? Under what conditions might this interaction lead to abrupt transitions to new climate and ecosystem states? 

Snapshots of simulated global vegetation pattern, so-called biomes, derived from an MPI-ESM model simulation of the last 8000 years (Brovkin et al., 2019) using a biomization tool developed in this group (Dallmeyer et al., 2019). Most striking is the widespread vegetation in the Sahara at 6000 BCE. The "Green Sahara Period" ended between 4000 BCE and 2000 BCE, earlier in the north than in the south and earlier in the west than in the east (Dallmeyer et al., 2020). In some regions the expansion of the Sahara occurred rapidly, much faster than the subtle, rather linear change in the forcing of the climate (Claussen et al., 2017).