Press release 20.9.2022

Improved soil carbon calculations for climate change applications

The soil carbon model Yasso produced by the Finnish Meteorological Institute has many influential climate-change-related applications in Finland and abroad. For example, the Yasso model is used for greenhouse gas inventories and future scenarios and for evaluating the effects of various measures in the land use sector. The new extensions to the Yasso model improve the reliability of the calculations and increase the possibilities of using the model.
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The Finnish Meteorological Institute is constantly developing the Yasso model with its collaborators. The now published extensions improve the reliability of the results in the model's application areas and expand the model's usage possibilities in scientific research.

The new extensions are:

  • improved Yasso20 model version

  • graphical user interface for Yasso07, Yasso15, and Yasso20 models

  • description of the carbon-13 isotope cycle

  • effect of mycorrhiza on the soil carbon cycle.

All material of the extensions is freely available on the Finnish Meteorological Institute's website.

The Yasso model is widely used internationally

Several countries use the Yasso model to calculate soil carbon emissions and sinks in their greenhouse gas inventories. These inventories are essential information sources for climate policy.

Yasso is the soil module of the German Max Planck Institute's climate system model and many other calculation systems. Thus, it is used in global climate change scenarios and climate impact assessments of forest and cropland treatment options.

The Yasso model has been used in about 200 research articles worldwide.

Further information:

Senior researcher Toni Viskari, Finnish Meteorological Institute, tel. +358 50 351 1524,

Research Professor Jari Liski, Finnish Meteorological Institute, tel. +358 40 748 5088,

Research coordinator Åsa Stam, Finnish Meteorological Institute, tel. +358 50 531 3477,

Descriptions of the extensions:

Viskari, T., Pusa, J., Fer, I., Repo, A., Vira, J., and Liski, J. 2022 Calibrating the soil organic carbon model Yasso20 with multiple datasets, Geosci. Model Dev., 15, 1735–1752.

Mäkelä, J., Arppe, L., Fritze, H., Heinonsalo, J., Karhu, K., Liski, J., Oinonen, M., Straková, P., and Viskari, T. 2022. Implementation and initial calibration of carbon-13 soil organic matter decomposition in Yasso model, Biogeosciences, 19, 4305–4313.

Huang, W., van Bodegom, P.M., Viskari, T., Liski, J., and Soudzilovskaia, N.A. 2022. Implementation of mycorrhizal mechanisms into soil carbon model improves the prediction of long-term processes of plant litter decomposition. Biogeosciences, 19, 1469–1490.

Huang, W., van Bodegom, P.M., Declerck, S., Heinonsalo, J., Cosme, M., Viskari, T., Liski, J. & Soudzilovskaia, N.A. 2022. Mycelium chemistry differs markedly between ectomycorrhizal and arbuscular mycorrhizal fungi. Commun Biol 5, 398.

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