Syllabus: 

GS3: Conservation, Environmental Pollution and Degradation, Environmental Impact Assessment.

Context: According to the study, the Antarctic Ice Sheet may have reached the tipping point of no return. 

More on the News 

• In the phase beyond this point, the ice sheet cannot stop melting even if global warming is contained or reversed.
• Researchers at the Norwegian research organization NORCE Research, United Kingdom's Northumbria University and Germany's Potsdam University (PIK) have confirmed hysteresis behavior in the Antarctic Ice Sheet.

Understanding the Antarctica’s ice

• Researchers used computer simulations both transient and equilibrium models of the Antarctic Ice Sheet to study its behaviour across natural glacial (cooling) and interglacial (warming) cycles over the past 800,000 years.
• The study stressed that once the tipping point is crossed, the ice sheets cannot return to their current stable state. Recovery would take thousands of years of temperatures at or below pre-industrial levels.
• Even a slight loss of Antarctica’s vast ice mass could have major impacts on coastal regions and the global economy. The study finds that a mere 0.25°C ocean temperature rise—or even maintaining current levels—could eventually trigger a 4-metre sea-level rise from the West Antarctic Ice Sheet. 
• This would occur once the ice sheet reaches its equilibrium state, the final extent after fully responding to present climate conditions, a process that may take many years due to its slow response.

Reasons of Ocean Warming

• The study emphasizes that ocean warming, rather than atmospheric temperature increases, is the primary driver pushing the Antarctic Ice Sheet toward this critical threshold. The warming of surrounding oceans destabilizes the ice sheet, accelerating its melting process.
• Antarctic ice melt is driven by rising global temperatures, which are causing both warming air and ocean water to melt ice sheets and ice shelves.
• Greenhouse gas emissions, particularly carbon dioxide, trap heat in the atmosphere and contribute to this warming, leading to increased surface melting and meltwater runoff. 

Global Implications of Ice Melt

• The study finds that a mere 0.25°C ocean temperature rise could eventually trigger a 4-metre sea-level rise from the West Antarctic Ice Sheet. 
• Rising sea levels and changing climates would adversely affect biodiversity and marine ecosystems.
• The loss of the ice sheet could disrupt global climate patterns, leading to more extreme weather events.