In “Sea-ice Physics”, we’ll take a closer look at sea-ice formation and change processes and show you in more detail how tiny ice crystals in the briny polar seas can form metre-thick ice cover, and how this cover changes with time. In addition, we’ll address all aspects of sea ice’s central role in the Earth system and for our planet’s climate. In “Sea-ice Biology”, we’ll focus on the amazing biodiversity in and on the ice. From tiny ice algae to polar bears and blue whales, you’ll learn about all sea-ice organisms great and small, and their roles within the food web. In “Sea-ice Measuring Methods”, you’ll learn how researchers investigate sea ice and which tools they use to do so – including research vessels, remotely operated vehicles, and satellites. Lastly, in “Sea-ice Modelling” we’ll fill you in on one of the most important methods in modern Earth system and climate research. We’ll show you how researchers use computers to virtually “reconstruct” sea ice and project how it will change in response to climate change, and what grave consequences its loss could have for the entire planet.