The SPLICE project (Structure, Photosynthesis and Light In Canopy Environments) sought to improve our understanding of global photosynthesis and hence our ability to model climate change, by considering the way in which the three-dimensional structure of plants interacts with light and how this in turn impacts on the uptake of carbon. It employed state-of-the-art techniques to measure the three dimensional structure and photosynthesis of forests and construct detailed computer simulations to create a virtual laboratory that we can use to improve simulations from climate models.