University of Helsinki and Finnish Meteorological Institute Reveal Critical Role of Soil in Dairy Emissions Calculations

(Image: University of Helsinki)

(IN BRIEF) A new study led by the University of Helsinki and the Finnish Meteorological Institute reveals that the carbon footprint of milk production may be significantly higher than current estimates suggest, particularly when soil carbon emissions are taken into account. Traditionally, assessments have focused on methane emissions from livestock, but this research highlights the critical role of soil organic carbon in determining overall environmental impact. Using life cycle assessment methods at the Viikki research farm, the study found that different calculation approaches yield widely varying results, with standard methods underestimating emissions. Northern climate conditions, including freeze–thaw cycles, were shown to reduce soil carbon storage capacity, while land-use changes—such as converting grassland to cereal crops—can dramatically increase carbon release. When soil emissions were included, the carbon footprint of milk rose by 41 percent. The findings underscore the need for more comprehensive and multidisciplinary approaches to measuring agricultural emissions and suggest that improved data could help farmers implement more effective, site-specific sustainability practices.

(PRESS RELEASE) HELSINKI, 21-Apr-2026 — /EuropaWire/ — University of Helsinki researchers, in collaboration with the Finnish Meteorological Institute, have identified that the environmental impact of milk production may be significantly underestimated when soil-related emissions are excluded from calculations. Their findings suggest that the carbon footprint associated with dairy production could be notably higher than commonly reported.

While assessments of milk’s climate impact have traditionally focused on methane emissions from cattle, this study emphasizes the importance of soil organic carbon dynamics—an element that has often been overlooked due to the lack of standardized measurement approaches. By incorporating soil carbon changes into the analysis, researchers provide a more comprehensive understanding of emissions linked to dairy farming.

The study was conducted at the University of Helsinki’s Viikki research farm, where scientists evaluated how fluctuations in soil organic carbon stocks influence the overall carbon footprint of milk production. The research focused on fields used for grass cultivation and cereal crop rotation, applying life cycle assessment techniques to account for environmental impacts across the entire production chain, from feed cultivation to manure management.

A key finding of the study is that the methodology used to estimate soil carbon changes has a substantial impact on the final results. Researchers compared three different calculation approaches and found significant variation in the outcomes. The widely used IPCC Tier 1 method, which relies on generalized assumptions, was shown to considerably underestimate emissions when compared to more precise field measurements and advanced carbon modeling techniques.

The study also highlights how northern climatic conditions influence soil carbon dynamics. Repeated freeze–thaw cycles during winter were found to damage grass growth, reducing the soil’s ability to capture and store carbon. As climate patterns become more unpredictable—with increased instances of freezing and drought—these effects may intensify, further diminishing the capacity of agricultural land to function as a carbon sink.

When grassland productivity declined, the release of carbon from the soil into the atmosphere increased significantly. The impact was even more pronounced when grassland was converted into cereal crop production, with carbon losses rising to nearly five times higher levels. When these soil emissions were included in the overall calculation, the carbon footprint of milk production increased by approximately 41 percent compared to estimates that excluded soil carbon changes.

Yajie Gao, a postdoctoral researcher involved in the study, explained that grasslands used for cattle feed can either act as carbon sinks or sources, depending on conditions. She emphasized that underground plant biomass plays a crucial role in maintaining soil carbon levels, making it essential to include soil dynamics in environmental assessments of food production.

Marja Roitto, another contributor to the study, underscored the importance of integrating multiple scientific disciplines—including soil science, atmospheric monitoring, and environmental assessment—to produce more accurate evaluations of agricultural emissions. She noted that improved data on soil carbon can help farmers adopt targeted practices to reduce emissions and move toward more evidence-based sustainability strategies.

The research represents a collaborative effort involving multiple teams within the University of Helsinki, including its Future Sustainable Food Systems research group, Environmental Soil Science group, and Viikki Research Farm, alongside contributions from the Finnish Meteorological Institute. The study forms part of the broader COVERE2 project supported by EIT Food.

Media Contacts:

Marja Roitto
Research Coordinator
Department of Food and Nutrition
marja.roitto@helsinki.fi
+358294121380

Yajie Gao
Postdoctoral researcher
Department of Agricultural Sciences
yajie.gao@helsinki.fi
+358294158309

SOURCE: University of Helsinki