Flash-frozen moss signals rapid climate change

Recently defrosted moss in the Andes suggests the world is warming rapidly, said an Ohio State University glaciologist Lonnie Thompson at last month’s American Geophysical Union meeting in San Francisco.

In 2002, on the Quelccaya ice cap in the Peruvian Andes at about 18,600 feet, Thompson found plants that had been recently exposed by melting ice. The plants were carbon-dated, and results showed they were alive about 5,200 years ago, when ice froze them quickly, showing climate change can be dramatic and quick, Thompson said.

Thompson returned to Quelccaya in August 2004, finding more plants emerging from the ice. Two of them dated to about 5,200 years ago, but the third, a clump of moss, came back from the carbon dating centre as being older than 48,000 years.

“One interpretation is that this ice field has not been smaller than it is today for 50,000 years,” Thompson said. “It had to be colder all the way back to the time it was frozen.”

Quelccaya ice cap is melting 40 times faster than it was in 1963, and other scientists at the meeting showed examples of “phenomenal” melting of glaciers in Greenland.