Three quarters of the ice-free land surface are used by humans in one way or the other. This has substantial consequences on climate because land use alters land cover, which in turn alters the exchange of energy, momentum, heat, moisture, carbon and other matter between vegetation and atmosphere. One third of cumulative anthropogenic CO2 emissions have been caused by deforestation and other land use changes. Locally, altered energy and heat fluxes due to a forest being transformed to pasture or a cropland being afforested may change surface temperatures by several degrees Celsius.
In our research we aim at (1) a better understanding of the processes through which land use influences climate from local to global scale (2) a more accurate quantification of the human disturbance of the Earth system. A key focus lies on the global carbon cycle – land use substantially alters the terrestrial carbon sinks and sources, yet is the most uncertain term in the global carbon budget.
Our most important tools are global vegetation modeling, climate modeling, and Earth system modeling. These numerical models are used to simulate different scenarios, including mitigation efforts through land use, and to switch on and off individual processes.
Prof. Dr. Julia Pongratz
Holder of the Chair of Physical Geography and Land Use Systems