by Paul Voosen, August 15, 2017

Scientists announced today that a core drilled in Antarctica has yielded 2.7-million-year-old ice, an astonishing find 1.7 million years older than the previous record-holder

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If the new result holds up, says Yige Zhang, a paleoclimatologist at Texas A&M University in College Station, the proxies will need to be recalibrated. “We have some work to do.”