TUM TREOS - Earth observation models for mapping radial tree growth at mesic sites

In recent decades, remotely sensed data and satellite imagery have experienced rapid development to now provide access to time-series with sufficient temporal resolution that allow for combination with tree-ring proxies on local scales and draw conclusions on regional and national scales. Earth observations from satellites (EOS) provide unique and accessible ways for monitoring and understanding the global carbon cycle, ecosystem shifts, forest productivity and vitality and other global planetary changes. EOS can be directly applied to detect changes in canopy features, which for example reflect direct negative effects of extreme drought (Buras et al., 2020), but to leverage the information encoded in satellite bands, on-the-ground calibration is needed. Tree-rings in temperate zones have a reliable annual resolution and encoded micro- and macro-environmental factors; and therefore represent an important calibration and validation method for remotely sensed products (Pearl et al., 2020). If the link between tree-rings and Earth observations from satellites is properly understood, it can support the scaling from individual trees from a site to the landscape scale, and enable the projections of growth variability and predicting the response of trees to climate on larger scales (Babst et al., 2018).

In this project, we seek to combine a large and specifically sampled tree-ring network covering 707 sites from Central and Eastern Europe with high-resolution satellite remote sensing images. The general aim is to identify the applicability and challenges associated with generating gridded growth products by means of remote sensing and gridded climate data and eventually provide forest-type and possibly species-specific gridded growth products for Central and Eastern Europe.

PI: Jernej Jevšenak (Alexander von Humboldt Fellow)

Supervising host: Dr. Allan Buras

Funding source: Alexander von Humboldt foundation