Canadian scientists have found the oldest chunk of ice in North America, the Globe and Mail reports, a discovery that suggests the earth’s carbon-laden permafrost may be more resistant to global warming than once thought. The 700,000-year-old chunk of Yukon ice has stayed frozen through two ancient, hotter times, which might mean a slower melt than feared for the permafrost that covers a quarter of the Northern Hemisphere’s land mass.
“There is a certain stubbornness to permafrost,” one researcher notes. Scientists warn that the discovery is no cause for complacency on climate change, but will be a valuable tool in predicting what to expect as the world heats up. Melting permafrost can cause sinkholes and significant land erosion, posing a serious threat to people living in the far north. It's “a glue that holds the Arctic together,” a student on the project adds.