New research indicates the Arctic Ocean may have passed a critical tipping point around 2009. As sea ice disappears, increased sunlight triggers a process called benthic denitrification, which strips essential nitrates from the water. This nutrient loss hinders plankton growth, the foundation of the marine food web. This shift has significant implications for global climate regulation. Because plankton remove carbon dioxide through photosynthesis, a less productive ocean means a weakened natural carbon sink, potentially accelerating atmospheric warming and disrupting North Atlantic fisheries.
