Predicted Future Changes in the Mean Seasonal Carbon Cycle: Impacts of Climate Change

In this study, we assessed the ‘Three Dimensional–Coupled Model Carbon Cycle–Forest Ecosystem Module’ (3D—CMCC—FEM) ability to simulate key carbon fluxes. We validated the model against observed data and investigated whether the seasonal carbon sink/source dynamics patterns are affected under two climate change scenarios across five European forest sites. More specifically, daily observed meteorological (1997–2005) data for model validation come from the Fluxnet2015 Dataset, and future climate scenarios (2006–2099) are projected from three Earth System Models. These models are part of the Climate Model Intercomparison Project 5 (CMIP5) and are driven by two Representative Concentration Pathways (RCP), specifically RCP 2.6 and RCP 6.0. The five case studies selected to represent key European forest species are chosen for their presence in the Fluxnet network. These sites include: the temperate European beech (Fagus sylvatica L.) forests at Collelongo, Italy (IT—Col), and Sorø, Denmark (DK—Sor); the maritime pine (Pinus pinaster Ait.) forest at Le Bray, France (FR—Lbr); the boreal Scots pine (Pinus sylvestris L.) forest at Hyytiälä, Finland (FI—Hyy); and the temperate Norway spruce (Picea abies (L.) H. Karst) forest at Bílý Kříž, Czech Republic (CZ—Bk1).