The impact of recent dramatic declines in Antarctic sea ice on the Earth system are uncertain. We reviewed how sea ice affects ocean circulation, ice sheets, winds, and the carbon cycle by considering theory and modern observations alongside paleo-proxy reconstructions. We found evidence for connections between sea ice and these systems but also conflicting results, which point to missing knowledge. Our work highlights the complex role of sea ice in the Earth system.

In this review article we present Svalbard’s unique geological archive, revealing its climate history over the last 540 million years. We uncover how this Arctic region recorded key global events, including end Permian mass extinction, and climate crises like the Paleocene-Eocene Thermal Maximum. The overall climate trend recorded in sedimentary successions in Svalbard is discussed in context of global climate fluctuations and continuous drift of Svalbard from near equator to Arctic latitudes.