Forests absorb 30% of current annual CO2 emissions through photosynthesis and growth, with tropical forests storing the majority of global live biomass in forests. However, due to climate warming, their ability to act as carbon sinks is uncertain, and they could even become carbon sources as trees stressed by climate extremes die and release their carbon back into the ecosystem. Here we will work within a permanent tropical forest plot network in Australia that spans both a rainfall and altitudinal gradient. This research project aims to improve our understanding of aboveground biomass dynamics in tropical forests using a novel multi-scale terrestrial and UAV laser scanning approach. The project's main research objectives are methodological, developing new allometric models and a multi-scale laser scanning approach, and ecological, understanding aboveground biomass dynamics, and assessing the impact of rainfall and altitude on biomass dynamics. The project's results will provide detailed insight into the 3D dynamics of vegetation at a large scale, and they will contribute to predicting, monitoring, and mitigating the effects of climate change.