Glacier Ice Algae Accelerate Greenland Ice Sheet Melting

Syllabus: GS3/ Environment

Context

• A study highlights how glacier microalgae accelerate Greenland Ice Sheet melting by efficiently colonizing exposed ice without additional nutrients.

Key Findings

• Ice Algae’s Role in Melting: Dark-pigmented microalgae grow rapidly on exposed ice surfaces.
  • Their pigmentation reduces ice reflectivity, increasing heat absorption and accelerating melting.
• Efficient Nutrient Uptake: Ice algae store phosphorus and sustain high carbon-to-nutrient ratios, enabling survival in nutrient-poor conditions.
• Significance: The study stresses the need to integrate biological factors into climate projections.
  • Ice algae have also been found in the Alps, Himalayas, and Alaska, suggesting that similar biological processes may contribute to glacier retreat globally.

Implications

• Accelerated Sea-Level Rise: The Greenland Ice Sheet is the largest contributor to global sea-level rise. 
• Disruption of Ocean Circulation: The melting ice releases large volumes of freshwater, which disrupt thermohaline circulation such as the Atlantic Meridional Overturning Circulation, AMOC.
• Impact on Global Climate: Darkened ice absorbs more heat, contributing to regional warming and amplifying Arctic temperature rise, which is already occurring at twice the global average.
• Marine and Polar Ecosystems: The influx of freshwater into the ocean alters salinity and nutrient cycles, affecting marine food chains.

Way Forward

• Improved Climate Models: Incorporating biological factors can enhance the accuracy of sea-level rise predictions.
• Mitigation Strategies: Addressing global warming to slow ice melt and minimize feedback loops.
• Further Research: Understanding ice algae dynamics in different glacier regions to assess their overall impact.

Greenland – Greenland, the world’s largest island, is an autonomous territory of Denmark located in the North Atlantic and Arctic Oceans.  – It lies between North America and Europe, with Canada to the west and Iceland to the east.  – Greenland’s 80% area is covered by the Ice Sheet, the second-largest ice mass in the world after Antarctica. – The capital and largest city of Greenland is Nuuk.

Source: TH