Sektion 1.3: Earth System Modelling
The geodetic parameters and fields, like the Earth's shape, its gravitational field and its orientation in space, are affected by many dynamic processes. The causes for their variation stem from all different parts of the Earth system, from the upper atmosphere to the core. By means of numerical simulations we trace these influences and draw conclusions about the dynamic processes from measured changes. For example, we model how the changes in the global wind systems in the atmosphere, the currents in the oceans and the water systems on land affect the Earth's rotation. We investigate the viscoelastic response of the Earth's crust to changes in the ice masses on the continents and the resulting changes in sea level. In contrast to short term elastic deformation, this isostatic adaptation to the decrease in ice loading can still be observed thousands of years after the last glacial ice has melted. We also model how variations of and interactions between convection currents in the Earth's mantle and its outer core produce the decadal oscillations in the Earth's rotation. A group of young scientists in our Section is concerned with the combination of geodetic observations with numerical simulations to expose the natural contributions of the atmosphere-hydrosphere system to climate variability.