The global ocean covers 70% of the Earth’s surface and forms the habitat of 78% of all animals on our planet. These habitats are shaped by the dynamics of the ocean, from large scale circulation and gyres all the way to coastal upwelling regions. In this module we will explore what drives ocean dynamics across scales, how the ocean interacts with the atmosphere and how this results in sea level variability on sub-daily to decadal time scales. The module is delivered through a combination of interactive lectures and applied workshops. Lectures develop the theoretical and mathematical foundations of geophysical fluid dynamics, while workshops provide opportunities to apply these principles to quantitative problems and computational investigations using real-world oceanographic scenarios. Assessment comprises a written examination and a quantitative modelling or data analysis coursework assignment, designed to evaluate both conceptual understanding and the ability to apply mathematical and physical reasoning to oceanographic processes.