Antarctic Sea Ice Loss Is Reshaping the Deep Ocean, Scientists Warn

The rapid decline of Antarctic sea ice since 2016 has triggered a dramatic shift in a crucial part of Earth's climate system, scientists say. In a paper published Wednesday, researchers documented a sharp increase in salinity (saltiness) in a vast layer of the Southern Ocean. This layer extends from about 2,300 to 4,000 feet deep and encircles Antarctica. The findings point to a major change in how the ocean mixes and stores heat — a process that affects climates far beyond the polar region. The study adds to growing evidence that the loss of sea ice is not only a surface-level problem but one that reaches deep into the ocean.