(Note: Proposal is pending):
Ecosystem respiration - the sum of plant and heterotrophic respiration - is a fundamental unknown in terrestrial carbon cycle research, resulting in significant uncertainty in global terrestrial carbon sink estimates and thus in all climate projections. TERRA will unravel key mechanisms governing ecosystem respiration and incorporate the knowledge learnt into an Earth System Model (ESM). This will deliver far more accurate estimates of remaining carbon budgets, critical information urgently needed to guide international climate policy in order to limit global warming to below 2oC, which could be reached in the next two to three decades1. TERRA will result in a transformational change in our understanding and representation of ecosystem respiration in all current carbon cycle research approaches (eddy covariance, ESMs and AI-based flux products), by using an interdisciplinary approach combining ground-breaking new technology, field and lab data collection, state-of-the-art theory, artificial intelligence and remote sensing data to produce new ecosystem-scale and global-scale respiration models and projections. By addressing this knowledge gap, TERRA will redefine current understanding of the global land carbon sink and ultimately support society by providing robust scientific advice to inform climate policy .