A massive Antarctic glacier is melting much faster than previously understood. It could double its contribution to global sea-level rise by the end of the century, according to research published on Saturday.
Scientists found that Antarctica’s Thwaites Glacier is losing mass rapidly. Warm ocean water pushes several kilometres beneath it and melts the ice from below.
Researchers estimate this process could cause Thwaites to contribute up to 30 millimetres to global sea-level rise by 2100. This assumes no additional warming beyond recent conditions.
Previous conventional ice-sheet models estimated the glacier would contribute roughly 15 millimetres by the year 2100.
Often nicknamed the Doomsday Glacier because of the severe consequences of its potential collapse, Thwaites covers roughly 192,000 square kilometres in West Antarctica. The massive ice formation acts as a barrier holding back vast quantities of inland ice alongside other glaciers such as Pine Island.
Thwaites currently accounts for about 4% of global sea-level rise. It has lost more than 1 trillion tons of ice since 2000, with losses continuing at approximately 50 billion tons every year.
Researchers focused their latest study on the grounding zone of Thwaites, where ice resting on bedrock begins to float on the sea.
Lead author Mattia Poinelli, a project scientist at UCLA, explained that a tidal pumping process enables warm water to reach deep beneath the ice and cause vigorous melting.
Simulations indicated a 60% chance of the glacier becoming detached from the underwater Mouginot Ridge by 2100. That could happen as early as the late 2030s.
Researchers warned that this shift could accelerate the glacier’s retreat. It would expose coastal communities worldwide to greater flooding risks than previously projected.
