A Biome-Specific Light Use Efficiency Model for Spatiotemporal Dynamics of GPP Across Europe Using PROBA-V and Sentinel-3 FAPAR

Estimates of gross primary production (GPP) derived from satellite remote sensing are crucial for assessing the terrestrial carbon dynamics. While model comparison is important, existing GPP products rely on a limited number of satellite sensors. In this study, the contemporary fraction of absorbed photosynthetically active radiation product derived from PROBA-V and Sentinel-3 was used to develop a new GPP product (EU-GPP) based on a light use efficiency (LUE) model for the European continent. EU-GPP accounted for the distinct responses of biomes to temperature and water stresses by incorporating biome-specific environmental scalars. Evaluation against eddy covariance GPP and model comparison against other LUE-based GPP products demonstrated the high model accuracy of EU-GPP within Europe. The model also responded well to the drought-induced stress, indicating its ability to capture interannual variability and the impact of extreme weather events. EU-GPP highlighted increasing GPP trends in croplands during 2014–2023, underlining the recent advancements in agricultural management practices. The Mediterranean forest ecosystems exhibited weakening GPP, suggesting the strong adverse impact of summer droughts on these ecosystems. This study presents an LUE-based GPP product based on novel remote sensing data and provides an independent perspective for the monitoring of GPP across the European continent.