Dr Stephen Rintoul is a physical oceanographer with a long-standing interest in the Southern Ocean and its role in the earth system. His research has contributed to a deeper appreciation of the influence of the Southern Ocean on regional and global climate, biogeochemical cycles and biological productivity. Born in the USA, he did his graduate studies at the MIT-WHOI Joint Program and postdoctoral work at Princeton before moving to Australia to take up a position at the CSIRO. His scientific interests include the dynamics of the Antarctic Circumpolar Current, the Southern Ocean overturning circulation, water mass formation, and the influence of Southern Ocean currents on biology and biogeochemistry. Primarily an observational oceanographer, he has led 15 expeditions to the Southern, Indian and Pacific Oceans. Over the last twenty years, Dr Rintoul has co-chaired international panels responsible for each of the major climate research programs carried out in the Southern Ocean. More recently, he led the Climate of Antarctica and the Southern Ocean program of the International Polar Year and the development of international plans for a Southern Ocean Observing System. He was a Coordinating Lead Author of the Oceans chapter in the 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). His scientific achievements have been recognised by many national and international awards.