Antarctica’s Thwaites glacier is retreating rapidly as a warming ocean slowly erases its ice from below, leading to faster flow, more fracturing and a threat of collapse, according to an international team of scientists.
The International Thwaites Glacier Collaboration (ITGC) consists of a team of nearly 100 scientists funded by the US National Science Foundation and UK Natural Environment Research Council dedicated to studying the vulnerable glacier.
The glacier is the size of Florida or Britain and currently contributes 4% of annual global sea level rise. If it does collapse, global sea levels would rise by several feet—putting millions of people living in coastal cities in danger zones for extreme flooding.
Thwaites sits in West Antarctica, flowing across a 120km stretch of frozen coastline. A third of the glacier, along its eastern side, flows more slowly than the rest—it is braced by a floating ice shelf, a floating extension of the glacier that is held in place by an underwater mountain.
The ice shelf acts like a brace that prevents faster flow of the upstream ice. But the brace of ice slowing Thwaites won’t last for long.
Beneath the surface, warmer ocean water circulating beneath the floating eastern side is attacking this glacier from all angles. This water is melting the ice directly from beneath, and as it does so, the glacier loses its grip on the underwater mountain. Massive factures have formed and are growing as well, accelerating its demise. This floating extension of the Thwaites Glacier will likely survive only a few more years.
The research revealed that if Thwaites were to collapse, it would drag most of West Antarctica’s ice with it. So it is critical to get a clearer picture of how the glacier will behave over the next 100 years. ITGC research, including future sea-level projections, will be vital for policymakers in their efforts to mitigate and adapt to the impacts of global sea level rise. M