The UN Ocean Decade program Digital Twins of the Ocean (DITTO) advances a core pillar of Digital Earth—a seamlessly integrated, data-rich, and predictive representation of the planet. By combining observations, physics-based models, and artificial intelligence, Digital Twins of the Ocean (DTOs) create dynamic, interoperable systems linking processes across the atmosphere, cryosphere, biosphere, and human systems.

This Union Session brings together advances in ocean science, Earth system modeling, and digital technologies. We invite contributions that strengthen DTO foundations, including coupled ocean–atmosphere dynamics, biogeochemical processes, data assimilation, cloud/HPC workflows, and AI-enhanced prediction, particularly studies revealing emergent behavior such as marine heatwaves, climate modes, and tipping risks.

We welcome contributions from modelers, observational scientists, data scientists, engineers, and practitioners integrating observations, modeling, AI, and interoperability to advance applications from climate services to coastal resilience.

Together, we aim to connect models, data, and decisions—shaping the digital ocean as a core pillar of Digital Earth.