Researchers from the Institute of Atmospheric Physics at the Chinese Academy of Sciences have developed a groundbreaking model to accurately measure the carbon sequestration capacity of global salt marshes. Named SAL-GPP, this is the first process-based model specifically designed for salt marsh ecosystems. Unlike traditional terrestrial models that often overlook coastal-specific environmental conditions, SAL-GPP uniquely integrates modules for tidal stress and salinity to simulate photosynthesis in both C3 and C4 plants across varying salt gradients. The study, led by lead author Zhou Zhuoya and corresponding author Professor Li Tingting, addresses a significant gap in blue carbon accounting caused by previous model limitations that missed coastal wetland contributions. The research team, which included collaborators from Nanjing University, Tsinghua University, and other CAS institutes, validated the model against flux tower sites worldwide. The results demonstrated excellent performance, achieving a coefficient of determination (R²) of 0.82 for daily productivity simulations. Using SAL-GPP, the scientists generated the world's first high-resolution 500-meter global dataset of salt marsh productivity for the decade spanning 2011 to 2020. The simulations indicate that global salt marshes have an average annual gross primary production of 66.89 ± 11.68 teragrams of carbon per year. The data highlights that hotspots in the southeastern United States, Western Europe, the southeastern coast of China, and Australia collectively contribute nearly 64 percent of the global total. Professor Li Tingting emphasized that while salt marshes are among the most efficient blue carbon ecosystems, their limited distribution often led to their underrepresentation in global assessments. The new dataset proves superior in accuracy compared to mainstream remote sensing products such as MODIS, GLASS, and GOSIF, as well as 17 simulations from the TRENDY project. This improved precision provides crucial scientific support for incorporating coastal wetlands into global carbon budgets more effectively. Published in Environmental Science & Technology, the study offers a robust tool for understanding the role of coastal wetlands in the global carbon cycle and supports more accurate climate policy planning. The development of SAL-GPP marks a significant step forward in quantifying blue carbon stocks and monitoring the health of these vital ecosystems.