Ana Bastos¹, Michel Ramonet², Dario Papale³, Ingrid Theodora van der Laan-Luijkx⁴, Naomi Smith⁴, Markus Reichstein⁵, Ulrich Weber⁵, Philippe Ciais², Wouter Peters⁶ and Werner Leo Kutsch⁷, (1)Ludwig Maximilians University of Munich, Dept. of Geography, Munich, Germany, (2)LSCE Laboratoire des Sciences du Climat et de l'Environnement, Gif-Sur-Yvette Cedex, France, (3)University of Tuscia, Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), Viterbo, Italy, (4)Wageningen University and Research, Wageningen, Netherlands, (5)Max Planck Institute for Biogeochemistry, Department of Biogeochemical Integration, Jena, Germany, (6)Wageningen University, Wageningen, Netherlands, (7)ICOS ERIC, Head Office, Helsinki, Finland