OREANDA-NEWS. Over the past million years, the Greenland has been losing it's ice sheet at least once, according to a report from the University of Vermont (USA). This is the conclusion reached by an international team of experts who studied the unique fossil plants and sediments from under the ice shell of the biggest island.

«The new study shows, that the deep ice at Camp Century – about 75 miles (120 km) from the coast and just 800 miles (1287.5 km) miles from the North Pole – has completely melted at least once in the last million years and has been covered in vegetation, including moss and possibly trees», the report said.

The samples have been preserved since 1966, when the US military at the Camp Century base in northwestern Greenland drilled into the ice to a depth of about 1.4 km and pulled out a core about 4.5 m long. The specimen then wandered through several scientific institutions, settling in Copenhagen in the 1990s. The real purpose of the camp was a top-secret operation, «Project Ice Worm», which aimed to hide 600 nuclear missiles under the ice near the territory of the Soviet Union. As a cover, the army presented the camp as a polar research station.

It is noted, that during most of the Pleistocene-the ice age spanning the last 2.6 million years, sections of ice in Greenland persisted even during interglacial periods, as evidenced by indirect evidence. The new research is consistent with data from two other ice cores from the center of Greenland collected in the 1990s.

It is noted, that scientists, in particular, measured the ratio of rare isotopes of aluminum and beryllium, which are formed in quartz only when the Earth is exposed to cosmic rays. Another test used rare forms of oxygen found in the ice inside the sediment to show, that the precipitation must have fallen at much lower altitudes than the height of the current ice sheet.

Researchers believe, that the melting of Greenland's ice can be quite fast, and if the island's ice sheet melts completely, it will cause an increase in sea level by 6 meters.