A major international review has highlighted a critical challenge for climate scientists: large gaps in knowledge along Antarctica’s coastline are limiting confidence in projections of future sea level rise. The study, published in Reviews of Geophysics and coordinated through the Scientific Committee on Antarctic Research (SCAR) RINGS Action Group, brings together expertise from glaciology, oceanography, geophysics and atmospheric science to assess what is known, and what remains unknown, about Antarctica’s coastal zone.
The Antarctic coast is far more than the continent’s outer edge. It is a dynamic region where grounded ice, floating ice shelves, ocean waters, the atmosphere and the underlying geology interact. Changes in this narrow zone can influence how quickly ice flows into the ocean and, ultimately, how much Antarctica contributes to global sea level rise.
According to the review, some of the most important uncertainties stem from limited observations of coastal bedrock topography and the cavities beneath ice shelves. These hidden features strongly affect how warm ocean water reaches glacier fronts and how ice responds to environmental change. Because ice sheet models depend on accurate information about these areas, missing or poorly constrained data can significantly affect projections of future ice loss.
The authors note that satellite missions have transformed the monitoring of ice movement and surface elevation across Antarctica. However, satellites cannot directly observe the seabed beneath ice shelves or the bedrock hidden beneath thick ice. Filling these knowledge gaps will require coordinated field campaigns, airborne surveys, marine observations and international collaboration.
The review concludes that improving understanding of Antarctica’s coastal environment is essential for reducing uncertainty in future sea level projections. As Antarctic ice loss continues to be driven largely by interactions between the ocean and the margins of the ice sheet, scientists argue that better observations of these coastal "blind spots" should be a global research priority.