Speedy melting of Doomsday glacier

• Context (OL): A study has unveiled a concerning revelation about Antarctica‘s infamous “Doomsday Glacier,” shedding light on its vulnerability to the warming oceans.

Doomsday glacier

• Antarctica‘s Thwaites Glacier, roughly the size of Britain, is a fast-moving glacier in West Antarctica.
• Because of the risk it faces — and poses — Thwaites is often called the Doomsday Glacier. Because of its size (1.9 lakh square km), it contains enough water to raise the sea level by more than half a metre.
• Thwaites’s melting already contributes 4% to global sea level rise each year.
• Thwaites are important for Antarctica as it slows the ice behind it from freely flowing into the ocean.

Credits: BBC

Vigorous melting

• Salty and relatively warm ocean water is infiltrating beneath Thwaites Glacier, leading to significantly speedy melting. This process, termed as “vigorous melting“, is eroding its stability.
• However, its potential collapse could lead to a staggering 10-foot rise in sea levels, posing a dire threat to coastal communities worldwide.
• Previous studies discovered a deep connection to the east through which deep water flows from Pine Island Bay. That study also attributed the melting to the heat transport caused by channels bringing warm water towards the glacier from the north.
• With melting, glaciers become light and float off the land where they used to be situated. The resulting retreating grounding line exposes more of a glacier’s base to seawater, increasing the risk of melting.
• Since the late 1990s, the glacier has seen a 14km retreat of its “grounding line.”

The grounding line is the point where the ice flowing off the land and along the seabed floats up to form a huge platform.