The evolution of the Antarctic Ice Sheet from inception through the Anthropocene

Abstract

The Antarctic Ice Sheet (AIS) stands as an enigmatic and awe-inspiring testament to the dynamic forces that have shaped our planet's surface through Earth history. In this review chapter, we provide an overview of AIS evolution since its inception. First, we review the techniques used to reconstruct past ice sheet evolution over a range of timescales, including Antarctic ice cores, methods for proximal marine environments, cosmogenic-nuclide geochronology, remote sensing, and ice sheet modeling, among others. Next, we describe key time periods and transitions in AIS dynamics, such as the initiation of continental-scale ice sheets, glacial–interglacial cycles, and equilibrium ice sheet dynamics during past glacial and interglacial states. We discuss how geological and observational data can be used to constrain ice sheet models, and how models, in turn, inform our interpretations of ice sheet reconstructions. Recognizing that humans have fundamentally altered Earth's climate system, we describe the observed human impacts in Antarctica in the Anthropocene, including ice shelf thinning and collapse, the Ozone hole, and ice sheet mass loss and grounding-line retreat. Lastly, based on the context provided from paleo-ice sheet reconstructions and historical observations, we offer our perspectives on future Antarctic change projected under 21st-century emissions scenarios. Reconstructions of the AIS demonstrate an enormous capacity of the ice sheet to change, with global consequences for the climate and sea level.