There was no Greenland ice a million years ago?

Bottles that were harvested from military operations during the Cold War and kept in freezers for decades may contain important new information about climate change and sea level rise. A study published in the National Academy of Sciences newsletter suggests that plant fossils found in soil samples taken from 1.6km-thick ice in the mid-1960s were warm enough to wipe out the Greenland ice sheet all over the world before humanity appeared. .

The study said that the sediment was investigated by drilling holes in the ice that covered most of Greenland. The University of Vermont research team explains that it is difficult to reach the bedrock and collect samples because the ice pressure is strong.

It is said that this sample contains many plants, some of which are visible to the naked eye. The research team explained that they found a lot of twigs on the bottom of the boots or small things scattered around the bottom of the boots after going hiking in the woods, which they found in frozen ground a million years ago.

The team analyzed various elemental isotopes to determine when the sample was last exposed to the sun and cosmic rays. Surprisingly, it is said that this plant was the same as it was a million years ago. One million years is equivalent to 10 ice ages.

Prior to the analysis of this sample, there was circumstantial evidence showing that the Greenland Ice Sheet was once completely melted. But rather than physical evidence, this fossil discovery conclusively shows that Greenland had an ice-free era with several plants inhabited. When Greenland ice completely melts, sea level will rise by 6 m. It is a time bomb for climate change. The current ice sheet is said to be melting six times faster than in the 1980s. It will take centuries for the climate to adapt to the changes caused by the increase in carbon dioxide and reach a new equilibrium. Knowing the history of the ice sheet leads to knowing the future of glaciers.

Under a climate system unaffected by humans, the Greenland Ice Sheet has completely melted. Even the climate could melt ice before humans release carbon dioxide into the atmosphere. In the future, if warming proceeds at an uncontrollable rate, there is a possibility that at some point the Greenland Ice Sheet will exceed the threshold and forcibly raise the sea level.

Samples were first taken from Greenland in 1966 on an expedition to a secret US military facility called Camp Century. The purpose of the expedition was to see if the nuclear missile could be hidden under the ice of the then Soviet Union. Of course, this plan ended in failure. The samples were transferred into a military freezer at the University of Buffalo and transferred to a freezer at a research facility in Denmark in the 1990s. In 2017, the research team was able to find samples while conducting inventory to move the facility’s freezers and conduct detailed analysis. Related information can be found here.