For the second year in a row, Antarctica’s sea ice has reached near-record levels. This reinforces concerns that human-caused climate change has initiated a lasting “regime shift” in the amount of ice that forms each year in the Southern Ocean.
“Last year we were talking about whether Antarctic sea ice was undergoing a regime shift. Not anymore,” says Edward Doddridge at the Institute of Marine and Antarctic Studies in Australia. “Antarctica answered that question pretty definitively for us. Now we’re talking about the impacts of this…
