The team brings extensive and complementary skills required for integration from carbon cycle observations to ESM implementation, ML and theoretical developments (CVs). The team is uniquely positioned to integrate knowledge across terrestrial and ocean models that have traditionally been developed in isolation. Team members provide needed expertise in data science, model development, calibration / parameters optimization, uncertainty assessment, and model evaluation. IPSL-LSCE and IPSL-ENS are part of IPSL Climate Modelling Center which is the long-standing hub for technical and scientific expertise for the ESM development in Challenge 4.