Global terrestrial carbon and water budgets are changing with an unprecedented rate. Observations and simulations of the terrestrial carbon and water budget are fundamental to forecasting the biosphere-atmosphere interaction under a changing climate. Although in reality, physical and physiological processes underlying carbon and water fluxes occur over a continuum of scales, most research efforts address a single scale. Therefore, the estimated change systematically depends on the scale of observation and is a significant contributor to the output uncertainties. This, along with the ever-increasing variety of observation methods, simulation and computation techniques, pose a challenge to inform process understanding by observations that are captured at multiple spatial and temporal scales.
In this session, we aim to review challenges associated with scaling processes of carbon and water fluxes from the leaf to the ecosystem, and eventually global scale. More specifically, we call for recent efforts in the systematic quantification of uncertainties associated with different scales in modelling exercises, transferability between measurement captured at the leaf (e.g. gas exchange), tree (e.g. sap flux, dendrometers) to ecosystem level (eddy covariance towers, UAVs, aircrafts and satellites), and modelling studies, which help in bridging observational datasets from multiple temporal and spatial scales.