DUACS DT-2024: 30 years of reprocessed sea level altimetry products

The Sea-Level Thematic Assembly Centers (SL-TAC), a component of the Copernicus Marine Services, provides near-real-time and delayed-time gridded sea level and surface current products at global and regional scales. These datasets, processed using the Data Unification and Altimeter Combination System (DUACS), are important for the ocean science community, enabling the study and monitoring of oceanic system evolution. 
 
Recently, DUACS has reprocessed 30 years of altimeter data, releasing the DT2024 products through the Copernicus Marine Service (CMEMS) and Copernicus Climate Change Service (C3S). These new products integrate updated geophysical correction standards, advanced mapping methods, and refined processing techniques, delivering significant accuracy improvements compared to the previous DT2021 release. 
 
This study provides a comprehensive overview of the CMEMS and C3S DT2024 products and assesses their quality against independent datasets. The analysis demonstrates that updated altimetry standards enhance accuracy, especially in coastal regions, reducing errors by approximately 10% due to improved ocean tide model corrections. Furthermore, the application of the Multi-Scale Inversion of Ocean Surface Topography mapping method has reduced mapping errors by 5%–7% in areas of high ocean variability. These enhancements position the DT2024 products as valuable resources for advancing our understanding of ocean dynamics and improving the accuracy of climate and oceanographic research.