A NASA-led study has discovered a giant cavity growing at the bottom of the Thwaites Glacier. The glacier is located in western Antarctica and flows into Pine Island Bay, a part of the Amundsen Sea.
According to NASA, the Thwaites Glacier is currently responsible for approximately 4% of global sea level rise. It holds enough ice to raise the world ocean by more than 2 feet.
The size of the cavity under Thwaites Glacier has raised serious concern. This is because large cavity would lead to the glacier being exposed to more heat and water and result in faster melting.
NASA has also observed that the western side of the glacier is melting very fast despite stable rate of grounding line retreat. Grounding line is the zone at which tidewater glaciers start to float in the ocean. Due to global warming, the ice at grounding lines of Antarctic glaciers have been melting. As a result, the grounding line retreats inland and exposes more of a glacier’s underside to sea water. This increases the rate of melting.
The cavity was revealed by an ice-penetrating radar in NASA’s Operation Ice Bridge. Operation Ice Bridge is an airborne survey that studies connections between the Polar Regions and the global climate.