Led by Imperial College London (ICL), Work Package 4 aims to develop and test a new implementation of the P model, driven by satellite retrievals of solar-induced fluorescence. It will incorporate recent findings on the adaptive nature of gross primary production responses to temperature and soil moisture. Additionally, WP4 will improve and reconcile global top-down and bottom-up inventories of isoprene, test modelled predictions of non-photochemical quenching, and enhance understanding of vegetation responses to extreme events such as heatwaves, droughts, and wildfires.