Abstract:

Plant physiological responses to increasing atmospheric CO2 concentration have been extensively explored using in-situ FACE experiments and ecosystem models. Earth system models incorporating these mechanisms provide opportunities to understand their impact on regional and global climate. In this seminar, I will present the current understanding of temperature and hydrological changes induced by plant responses to increasing atmospheric CO2. Idealized model simulations of a non-linear 1 % per year increase in CO2 show widespread decreases in stomatal conductance and transpiration, which, in turn, amplify climate warming and alter precipitation patterns across tropical continents. However, multiple sources of uncertainty make it challenging to robustly quantify the magnitude of these effects or their subsequent impact on vegetation carbon storage, highlighting a new open question and the need to discuss plant physiological responses to rising CO2 in the context of natural climate solutions.