A Recent Discovery on Life under Antarctic Ice Shelf

Why is in News?

Scientists have discovered potential new species on the Antarctic seafloor exposed by the A-84 iceberg's (detached from the George VI Ice Shelf) breakaway.

• Ice shelves- These are floating tongues of ice that extend from grounded glaciers on land.
• Formation - They are formed by the accumulation and compaction of snow, which, over time, turns into ice.
• Ice shelves are common around Antarctica, and the largest ones are the Ronne-Filchner, Ross and McMurdo Ice Shelves.
• These are crucial for understanding climate change and sea level rise.
• Role - Ice shelves stabilize land-based glaciers, acting as a "buttress" against the ocean.

Key Highlights

• Unveiling a Hidden Ecosystem - Following the breakaway of the A-84 iceberg, a remotely operated submersible (ROV) recently explored the newly exposed Antarctic seafloor.
• The team of scientists conducted deep-sea exploration at depths of up to 1,300 metres beneath the ice.
• They discovered a thriving ecosystem with an abundance of marine species, including
  • Icefish and Octopi – Adapted to extreme Antarctic conditions.
  • Giant Sea Spiders – Deep-sea arthropods that have evolved in isolation.
  • Large Corals and Sponges – Supporting complex underwater habitats.
  • Giant Phantom Jelly – A rare jellyfish species that can grow up to one metre wide.
  • Vase-shaped Sponges – Some of these specimens could be hundreds of years old.

Scientific Significance

• The discovery was unexpected as these deep-sea environments were assumed to lack sufficient nutrients for complex ecosystems.
• Normally, deep-sea life relies on organic material from photosynthetic organisms falling from the ocean surface.
• However, the 150-metre-thick ice shelf covering this area for centuries blocked access to surface nutrients, making the existence of rich biodiversity surprising.
• Scientists speculate that essential nutrients might be transported by
  • Ocean Currents – Carrying organic matter from distant areas.
  • Glacial Meltwater – Potentially introducing nutrients trapped in ice.
  • Unknown Biological or Chemical Processes – Yet to be fully understood.

Global Research Initiative

• The expedition was part of Challenger 150, a UNESCO-endorsed global deep-sea research initiative.
• Conducted by an international team of scientists, the mission aimed to explore the world’s least-studied marine environments.
• The research will provide crucial insights into climate change, ice shelf dynamics, and deep-sea ecosystem functioning.
• Previous signs of bottom-dwelling life under Antarctica’s ice shelves were only reported in 2021, making this discovery a major advancement in marine science.

Reference

The Indian Express - Life under Antarctic ice shelf