Antarctica's Thwaites Glacier Melting Faster Under Ocean Influx, Study Finds
New research reveals warm seawater reaching deep underneath Antarctica's massive Thwaites Glacier could double its projected sea level contribution by 2100.
At a glance
- Warm seawater reaching deep beneath Antarctica's Thwaites Glacier is melting its core faster than previously projected.
- The glacier could add 30 millimetres (1.2 inches) to global sea levels by 2100, double earlier estimates.
- There is a 60 percent chance the glacier unpins from a stabilizing underwater bedrock ridge by the end of the century.
Warm seawater is penetrating deep beneath Antarctica's Thwaites Glacier, accelerating its retreat and potentially doubling its projected contribution to global sea levels by 2100, according to a study published in Nature Communications.
The research, conducted by glaciologists at the University of California and NASA's Jet Propulsion Laboratory, shows that ocean water is flowing under the glacier's core through a dynamic tidal pumping process. Rather than resting on a fixed boundary, the ice shifts with tides across a wider grounding zone, allowing warmer seawater to circulate deep beneath the ice and drive vigorous melting.
Spanning roughly 192,000 square kilometres (74,130 square miles)—an area roughly the size of Senegal and larger than the US state of Florida—Thwaites is the largest glacier on Earth. Nicknamed the "Doomsday Glacier," it forms part of the West Antarctic ice sheet and functions as a critical natural dam alongside neighbouring glaciers. Ice loss from Thwaites already accounts for four percent of global sea-level rise, with more than 1,000 billion tonnes of ice lost since 2000.
Under the new projections, the glacier could add up to 30 millimetres (1.2 inches) to global water levels by the end of the century, even without accelerated atmospheric warming. The increased melting is also weakening its connection to the seafloor, with researchers identifying a 60 percent chance that Thwaites could detach from the Mouginot Ridge, an underwater bedrock structure that currently provides vital structural stability.
While a full collapse is not forecast for several decades or centuries, scientists warn that melting cannot easily be reversed. Separate research published by the British Antarctic Survey found that Thwaites will continue shedding ice for at least the next 150 years, even under extreme oceanic cooling conditions.
Source: Al Jazeera.
Questions and answers
- Why is Thwaites Glacier melting faster than anticipated?
- Tidal movements push warm seawater deep underneath the glacier's dynamic grounding zone, causing aggressive melting from beneath the ice.
- How much could Thwaites Glacier raise global sea levels by 2100?
- New modeling indicates the glacier could add up to 30 millimetres (1.2 inches) to sea levels by the end of the century, double previous forecasts.
- What is the Mouginot Ridge?
- It is an underwater bedrock formation that helps anchor Thwaites Glacier. Researchers estimate a 60 percent chance the glacier will unpin from it by 2100.
