ABSTRACT
Large model uncertainty in projected future soil carbon (C) dynamics has been well documented. However, our understanding of the sources of this uncertainty is limited. This chapter is designed to illustrate the projection uncertainties induced by model structures and parameter values. Three representative soil carbon models are compared in terms of their predictions of soil carbon change in a future climate warming scenario. The parameter values in each model were derived by fitting modeled soil carbon to observations. We see that uncertainty often increases with complexity of a model. The larger uncertainty in the complex models suggests that we need to strike a balance between model complexity and the need to include diverse model structures in order to forecast soil C dynamics with high confidence and low uncertainty.
