Poppy Seed Found Beneath Greenland Ice Sheet Shows Vulnerability to Dramatic Melting

During a past warm period, much of Greenland was likely covered in vegetation, as this rocky outcropping is today.

During a past warm period, much of Greenland was likely covered in vegetation, as this rocky outcropping is today. Joshua Brown

Scientists have recovered an intact poppy seed and other plant remnants buried under two miles of ice in the heart of Greenland. The finding indicates that during a prior warm era, Greenland was almost entirely ice-free — an ominous precedent on a rapidly heating planet.

The poppy seed, as well as the compound eye of an insect, broken willow twigs, and spikemoss spores were found in sediment recovered from the tip of an ice core that had been held in storage since 1993. “We now have direct evidence that not only was the ice gone, but that plants and insects were living there,” said lead author Paul Bierman, of the University of Vermont. “And that’s unassailable. You don’t have to rely on calculations or models.”

The discovery, published in the Proceedings of the National Academy of Sciences, suggests that the Greenland ice sheet had almost completely melted at some point in the last million years. Writing in The Conversation, authors warn that humans are “on pace to warm the Arctic and Greenland beyond temperatures they have experienced for millions of years.” If the Greenland ice sheet were to thaw today, they note, it would raise sea levels by more than 20 feet over the coming centuries.

“Look at Boston, New York, Miami, Mumbai, or pick your coastal city around the world and add 20-plus feet of sea level,” Bierman said. “It goes underwater. Don’t buy a beach house.”

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