Authors: Tuomas Häme and Jukka Miettinen
Last week, the Forest Carbon Monitoring team participated in the 4th Carbon from Space Workshop. The Workshop was organized in Frascati, Italy, by the European Space Agency (ESA), in collaboration with Global Carbon Project, CEOS, NASA and the European Commission. The workshop brought together the Earth observation, in situ and Earth system science communities to interact and discuss the challenges in understanding the carbon cycle, focusing particularly on the terrestrial component and its interactions with the ocean and atmosphere.
Approximately 100 on-site and 200 on-line participants attended the workshop which spread over four days. It covered a wide range of topics from new sensors, model-data interactions and digital twins to thematic sessions focusing on land use, forests, and arctic areas. Sessions on carbon balance and its stocktake, with its feedback mechanisms on climate and weather events were also included.
A major part of the presentations discussed global carbon-related processes. Research on atmospheric and terrestrial carbon monitoring using several low-resolution sensors were presented, with new algorithms to estimate photosynthetic activity. Carbon flux models based on climatic data are central in these approaches and variability in the models affect greatly the estimates. Further development of the uncertainty assessment was clearly expressed also for the higher resolution biomass and carbon inventories. As with the low-resolution assessments, inventories using spaceborne and terrestrial data have shown major variability between projects. Collection and availability of in-situ reference data should be improved.
Satellite data with a few meters or sub-meter resolution are coming to national-level or even global-level inventories of forest carbon. Very high-resolution satellite data have shown strong potential particularly in the barren regions where tree cover is sparse. Another rising theme is the Digital Twin of forests. VTT’s on-site presentation showed how the outputs of the Forest Flux and Forest Carbon Monitoring projects have been and can be used in Forest Digital Twins to simulate different scenarios of forest variable and carbon balance.
Overall, the workshop highlighted the great progress that has been made over the past 20 years in carbon monitoring and the great potential of new Earth observation based approaches. On the other hand, it became yet again very clear that further development on terrestrial carbon monitoring from space is urgently needed. In particular, mechanisms for the reporting of carbon balance and for evaluating the impacts of management and policy decisions on the carbon balance must be further developed. Projects like the Forest Carbon Monitoring are in key position to enable improved monitoring of terrestrial carbon in the future and thereby affect the future our planet.