Southeast Asia holds a globally significant proportion of the world’s green carbon (terrestrial forests) and blue carbon (mangroves). However, these ecosystems are currently managed in silos, ignoring the critical ridge to reef connectivity where upstream terrestrial land-use change directly degrades downstream mangrove health through sedimentation. Additionally, unchecked coastal infrastructure development is altering local hydrodynamics, leading to severe shoreline erosion and mangrove die-back. Furthermore, persistent cloud cover in the region creates massive data gaps in optical satellite assessments, hampering accurate Nationally Determined Contributions (NDC) accounting. This project proposes a unified green to blue diagnostic framework focusing on critical ridge to reef gradients in Malaysia (Larut-Matang forests), Cambodia (Peam Krasorb Wildlife Sanctuary) and the Philippines (Aklan). We will employ a hybrid digital twin approach, fusing AlphaEarth Foundations satellite embeddings (AI) with Delft3D flexible mesh hydrodynamic modelling. The AI will generate cloud-resilient annual assessments of land-cover change and identify optimal mangrove restoration sites, while the hydrodynamic component will simulate sediment transport to validate specific replanting viability. The project aims to provide policymakers and stakeholders with a dashboard to harmonise terrestrial and marine carbon policies, ensuring the longevity of Southeast Asia’s critical carbon sinks.