
Antarctic sea-ice decline has turned deep ocean shielding layer saltier, study finds
The shift reverses decades of freshening in Antarctic intermediate water and may let more heat reach the deep ocean
A layer of water that shields the deep ocean from surface heat has been turning saltier, denser and sitting deeper since Antarctic sea ice began its sharp decline in 2016, according to research published Wednesday. The reversal of a decades-long freshening trend could allow more heat to reach deeper waters, with consequences for the world's climate that scientists say are unknown.