Overview

• The Antarctic Circumpolar Current (ACC), Earth's most powerful ocean current, is projected to slow by 20% by 2050 under high carbon emissions scenarios.
• Freshwater from melting Antarctic ice sheets is diluting the salty ocean, disrupting the current's density-driven circulation patterns.
• A weaker ACC could allow invasive species to reach Antarctica, disrupting ecosystems and threatening native wildlife like penguins.
• The slowdown may also reduce the ocean's capacity to absorb heat and carbon dioxide, amplifying global climate change impacts.
• Researchers emphasize that reducing greenhouse gas emissions could limit ice melting and potentially avert the projected decline in the ACC.