The Thwaites Glacier, located in West Antarctica, has been termed the “Doomsday Glacier” due to its potential to significantly contribute to global sea-level rise if it were to collapse or melt at an accelerated pace. Here are the reasons why:

1. Massive Size and Ice Loss: Thwaites Glacier is one of the largest glaciers in Antarctica and already accounts for approximately 4% of annual global sea-level rise. It holds enough ice to raise global sea levels by around 65 centimeters (about 2 feet) if it were to completely melt.
2. Vulnerable to Instability: The glacier is particularly unstable because it rests on a bed that slopes downward as it moves inland. This geometry means that once the front of the glacier starts retreating, it could trigger a self-sustaining process that leads to rapid disintegration.
3. Feedback Loops: The melting of the Thwaites Glacier could set off a chain reaction. As ice melts, it exposes darker ocean water and land, which absorbs more solar heat, further accelerating the melting process—a feedback loop that exacerbates the problem.
4. Potential Collapse: Studies indicate that the glacier’s grounding line (where the glacier lifts off the seabed and begins to float) is retreating, and warm ocean currents are melting the ice from beneath. There are concerns that a complete collapse of the glacier’s ice shelf could destabilize the entire glacier system.
5. Global Implications: If the Thwaites Glacier collapses, it could destabilize neighboring glaciers in the Amundsen Sea Embayment region, which together contain enough ice to raise global sea levels by several meters. Such a dramatic increase in sea levels would have devastating consequences for coastal cities, island nations, and ecosystems worldwide.

These factors combine to give the Thwaites Glacier its ominous nickname, emphasizing the urgent need for scientists to monitor and understand its behavior to predict and mitigate potential future impacts on our planet.