Bering Sea winter ice shrank to its lowest level in 5,500 years in 2018

Five millennia of climate shifts impacting the ice is recorded in peat from an Arctic island

Bering Sea ice

The Bering Sea (shown) may be ice-free year-round by the end of the century. A new study finds that increasing climate-altering CO2 can lead to reduced ice in the winter as well as the summer.

Jim Williams/iStock/Getty Images Plus

Sea ice in the Bering Sea, on the southern margin of the Arctic Ocean, dwindled to its smallest wintertime expanse in 5,500 years in 2018, new data show.