Earth's oceans are a complex system, and their interconnected nature has global implications. Around Antarctica, cold and dense waters form in the depths of the Southern Ocean. This is known as Antarctic Bottom Water (AABW). It comprises most of the deepest abyssal part of the ocean and approximately a third of the volume of the planet's marine environments. AABW has an important function in global circulation and the overturning patterns of the ocean, distributing heat, salt, carbon and nutrients northward into basins across the planet.