Integrating Nitrogen and Carbon In Models of the Earth (IN CRIME)
12 / 2009 - onbekend
Of the anthropogenically emitted greenhouse gas CO2 only about 45% remains airborne, terrestrial vegetation takes up 30%, thus providing a large discount on climate change. However, the processes behind the terrestrial sink are not yet well understood. Climate warming and CO2 fertilisation are often named as potential causes, but recently the role of the nitrogen cycle is more emphasised, since most ecosystems on Earth are nitrogen limited. Nitrogen emission by traffic, industries and agriculture cause atmospheric deposition downwind, and global warming increases nitrogen mineralization in the soil. Nitrogen has the capability of strongly changing the terrestrial carbon balance as well as the ecosystem energy balance. The nitrogen cycle also interacts directly with climate through the emissions of the greenhouse gas N2O. This project aims to use a coupled nitrogen-carbon model, as part of the dynamic global vegetation model LJP, integrated in the climate model EC-Earth, to verify the carbon and nitrogen cycles and to quantify the feedback of the coupled nitrogen-carbon cycle on future climate. Observational data from both CarboEurope and NitroEurope among other global datasets, are available for verification. We expect the largest impacts in northern regions, since there the interactions between vegetation and climate are strongest. The project addresses the need for better understanding of future climate change.