Improving our understanding of the terrestrial carbon cycle’s responses to environmental change is a key ingredient in progressing climate science. New research in this field, involving CMCC scientist Manuela Balzarolo, looks at how remote sensing-based models for gross primary production in plants can be improved both theoretically and empirically in an effort to provide more accurate results. 

Gross primary production (GPP) in plants – the total amount of carbon dioxide absorbed by plants through the photosynthetic reduction of CO₂ into organic compounds – is essential for life on land, as it represents the primary source of carbon for terrestrial ecosystems.

How we monitor and quantify these processes is an area of scientific interest and remote sensing technologies, especially satellite-based measurements of the fractional absorption of light by vegetation, provide a powerful tool for monitoring and analyzing GPP patterns and trends globally. However, many current remote sensing-based models for GPP lack solid theoretical or empirical foundations; they often conflict with one another and are becoming increasingly complex without showing a corresponding improvement in accuracy.

A new Perspective, published in the journal Nature Reviews Earth and Environment – bringing together researchers from leading institutes around the world, including CMCC’s Manuela Balzarolo – addresses the challenges involved in improving the robustness and reliability of remote sensing-based models, as well as proposing a new generation of more reliable models for GPP.

“The paper focuses on several principles for the development of new-generation remote sensing-based models arguing that models should use multiple remote sensing input data and adopt universal representations of ecosystem processes to avoid artificial boundaries between plant functional types,” says co-author of the study Balzarolo, who also suggests that uncertainties propagation in data input and models should be addressed to describe uncertainty in the simulations.

The paper was designed during the ESA Terra-P project, led by esteemed ecologist from Imperial College London, Colin Prentice, for the application of new approaches to satellite-based monitoring of primary production in global carbon cycle research.

“Thanks to the contribution to this research in Nature Reviews Earth and Environment I started thinking about innovative ideas for carbon modeling which had not yet been developed,” says Balzarolo. “This then took shape with the funded Horizon project CONCERTO that I will lead starting from January 2025, collaborating with Colin Prentice and many other Terra-P partners.”

Improved reliability of GPP and biomass production estimates, through advances in technology and data availability, will enhance our understanding of carbon cycling and vegetation function, as well as the overall response of the terrestrial carbon cycle to environmental change.

For more information:

Prentice, I.C., Balzarolo, M., Bloomfield, K.J. et al. Principles for satellite monitoring of vegetation carbon uptake. Nat Rev Earth Environ 5, 818–832 (2024). https://doi.org/10.1038/s43017-024-00601-6