Ice loss from Pine Island Glacier has contributed more to sea-level rise over the past four decades than any other glacier in Antarctica. Although it is one of the most intensively and extensively investigated glacier system in Antarctica, different model projections of future mass loss give conflicting results; some suggesting mass loss could dramatically increase over the next few decades, resulting in a rapidly growing contribution to sea level, while others indicate a more moderate response. In a paper published in Nature Geoscience, scientists from the University of Bristol, UK, describe how they used information from CryoSat to help clarify the situation. They discovered that the pattern of ice loss is evolving in complex ways, both in space and time.
Rates in the fast-flowing central trunk of the glacier have decreased by about a factor of five since 2007 – and this is the opposite of what was observed prior to 2010. These new results suggest that rapid migration of the grounding line, the place where the grounded ice first meets the ocean, is unlikely over the next decades, without a major change the role of the ocean in ice loss. Instead, the results support model simulations that imply that the glacier will continue to lose mass, but not at much greater rates than present.