Upscaling carbon fluxes to a landscape

The overarching aim of the thesis work is to improve understanding of ecosystem scale carbon exchange at northern latitudes using remote sensing methods and to use these results to upscale carbon fluxes to regional and national levels. The specific objectives are to understand the influence of spatial heterogeneity and temporal variations of vegetation and land surface on ecosystem carbon fluxes, namely gross primary production (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE). Temporal variations of vegetation are mainly related to phenology, water stress, light properties and length of growing seasons.

European satellite instrument Sentinel-2 provided high-resolution spectral data on photosynthetic activity and vegetation heterogeneity. Carbon flux data from Eddy Covariance sites are matched with the satellite data using a footprint model. Empirical models relying to the relationship between EC-derived fluxes and remotely sensed vegetation indices are used to upscale carbon fluxes from EC sites to the landscape level.