Satellites map carbon sequestered by forests, with accuracy of up to ten metres

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Led by VTT, the EU North State project has developed a new method of using satellite images to evaluate the forest carbon balance. The carbon balance indicates how much carbon is sequestered or released by forests each year. This enables the carbon balance to be displayed on digital maps, with an accuracy of up to ten metres.

Led by VTT, the EU North State project has developed a new method of using satellite images to evaluate the forest carbon balance. The carbon balance indicates how much carbon is sequestered or released by forests each year. This enables the carbon balance to be displayed on digital maps, with an accuracy of up to ten metres.

The technique involves mapping the key features of forest areas and forests – such as the location, main tree species, height and biomass – from images provided by the European Sentinel satellites. These digital images are fed into a model, alongside climate data. The result is carbon sequestration maps. Such maps reveal which areas are carbon sinks or carbon sources. This information can be used for activities such as planning forest management and assessing climate impacts.

The simplest maps show the amount of carbon sequestered through photosynthesis, but take no account of carbon released by the decomposition of organic matter. More refined products take account of carbon released by living plants and carbon emissions from the soil. They provide a more precise idea of the carbon balance, but require the best source data. It was possible to create more advanced carbon balance maps of Finnish territory because sufficient ground reference data was available for guiding satellite image interpretation.

"The partners in the project developed advanced methods of interpreting satellite and drone images. The University of Helsinki did the computing for the final carbon balance maps, based on VTT's satellite image interpretation. We had to invent a new approach to processing such huge quantities of data," says Research Professor Tuomas Häme.

Read more at VTT Technical Research Centre of Finland

Photo credit: Miguel.v via Wikimedia Commons