George VI Ice Shelf

Syllabus: GS1/ Geography

In News

• Scientists under the Challenger 150 initiative uncovered thriving deep-sea ecosystems beneath the George VI Ice Shelf in Antarctica.

About George VI Ice Shelf

• Location: Situated in George VI Sound, separating Alexander Island from Palmer Land, adjacent to the Bellingshausen Sea in the Southern Ocean.
• Governance: Falls under the Antarctic Treaty System, with active research led by countries like the UK and USA.
• Geographical Features:
  • Length: Extends from Ronne Entrance to Niznik Island 
  • Rich in floating ice shelves, subglacial ecosystems, and complex underwater geography

Key Findings under Challenger 150 Initiative

• Flourishing Deep-Sea Ecosystems:
  • Discovery of large corals, sponges, icefish, and giant sea spiders
  • Ecosystems survived despite being cut off from sunlight and surface nutrients for centuries.
  • The presence of complex life in absence of known nutrient sources suggests unknown nutrient transport pathways, opening new avenues for research.
• New Species Identified:
  • Giant phantom jellyfish
  • Octopi, vase-shaped sponges (possibly centuries old), and sea spiders

About Deep-Sea Ecosystems

• Definition: Marine ecosystems occurring below 200 metres, extending into the aphotic zone—which comprises 90% of Earth’s marine habitat.
• Significant Habitats:
  • Abyssal Plains: Support species like sea cucumbers sustained by marine snow. Marine Snow are organic particles from upper layers, aiding food chains and carbon sequestration.
  • Hydrothermal Vents: Host chemosynthetic life (e.g., tubeworms, yeti crabs)
  • Whale Falls: Create temporary yet productive ecosystems (e.g., hagfish)

Significance of the Discovery

• Scientific Relevance: Overshadow previous assumptions that extreme, nutrient-deprived environments cannot support complex life.
  • Opens new frontiers in marine biology, ecology, and geosciences.
• Climate Change Insights: As polar ice shelves melt due to global warming, these ecosystems may undergo dramatic shifts.
  • Studying them helps understand ecosystem resilience and predict environmental responses to climate change.
• Marine Conservation Imperative: Emphasizes the need for international frameworks to safeguard fragile marine biodiversity, particularly in the Southern Ocean.

International Cooperation & Ocean Decade

• The Challenger 150 programme is part of the UN Decade of Ocean Science for Sustainable Development (2021–2030).
• It underscores the role of multilateral scientific collaboration in exploring and conserving the deep ocean.
• Endorsed by UNESCO/IOC, the initiative aligns with global sustainable development goals, especially SDG 14 (Life Below Water).

Source: IE