The Circumpolar Current works as a regulator of the planet's climate. Its origins were thought to have caused the formation of the permanent ice in Antarctica about 34 million years ago. Now, a study led by the University of Barcelona, the Instituto Andaluz de Ciencias de la Tierra (CSIC) and the Imperial College London (United Kingdom) has cast doubt on this theory, and has changed the understanding of how the ice sheet in Antarctic developed in the past, and what this could mean in the future as the planet's climate changes.