Aspects of research

With recent summers in Europe characterized by heatwaves, droughts and extreme localized precipitation events, it has become evident that changes in climate and land-use have strongly influenced the magnitude and patterns of evapotranspiration, precipitation and cloud formation via feedbacks between the land and the atmosphere. Vegetation plays a critical role in modifying these dynamic interactions as it interlinks exchanges in energy, water and carbon.


The diversity of mechanisms responsible for interactions between the (vegetated) land and the atmosphere range from the size of the stomata (10 – 100μm) to the size of the atmospheric boundary layer (~1 km). This includes temporal dynamics on time scales of minutes (passing clouds and plant responses), days (diurnal solar cycle) and seasons (seasonal solar cycle and vegetation dynamics) (TABLE).
Clouds as well as atmospheric-boundary layer dynamics disturb radiation and turbulence conditions in and above the vegetation canopy and, subsequently, the energy and moisture fluxes that affect clouds. Although these effects occur at short spatiotemporal scales, they have profound impacts on the regional and global CO2 budget. CloudRoots aims to advance current understanding of land-atmosphere dynamics. Therefore, it is essential to investigate, using first-principles, the cross-scale interactions between the relevant processes in an integrated observation – simulation system.

scales table


CloudRoots methodological approach is based on developing and using multiple observations and modelling approaches to bridge the gap between scales and unravel the links between the biochemical and physical processes (see SCALES and DISCIPLINES). In measuring, the main novelty is to be able to observed the links between the rapid surface turbulent fluxes (1-minute) perturbed by clouds and turbulence. In simulating, we attempt to resolve explicitly the evolution of the main processes to infer generic cross-scale relationships. By integrating observations and numerical experiments, we will improve our understanding of the transient exchange of energy, water and carbon from the leaf to the boundary layer over heterogeneous surfaces.


In addition of the standard turbulent and meteorological observations, CloudRoots will test the innovating technique to combine stable isotopologues measured at a high-flow rate with the scintillometer technique. This measurements will be supported by ecophysiology measurements. The main goal is to observe 1-minutefluex of the isofluxes to calculate the partitioning of water and carbon fluxes during transitional situations dominated by clouds.